A N O AK S PRING L ANDSCAPE : H IS TO R Y , E C OLOG Y ,
A ND
M A NA GEM EN T
A T THE
O AK S PRING G ARDEN F OUNDATION
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A N O AK S PRING L ANDSCAPE : H IS TO R Y , E C OLOG Y ,
A ND
M A NA GEM EN T
A T THE
O AK S PRING G ARDEN F OUNDATION
M IC HA EL G A IGE I LL USTRA TI ON S : A UT UMN V ON P LI NSKY
A PR IL 2018
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1 2
C ONTENTS Introduction
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Part 1: Landscape Context Geographic Overview Geologic History Climate Eastern Deciduous Forest Presettlement Forest Human History
10 11 17 25 29 35 43
Part 2: Inventory and Recommendations Rocky Outcrops Soil Springs Ponds Goose Creek Vegetation Trees Exotic Species Fauna Indigenous Artifacts Stone Walls Cemetery Property History Special Places
66 67 71 82 86 92 98 112 119 127 136 142 148 151 156
Part 3: Management Synthesis Conservation Context Climate Change Vegetation Plan Grasslands Scattered Trees Reforestation Wetlands Forest Understory Woodland Garden Other Areas Watchable Wildlife Trails Planning
172 173 176 178 180 186 190 197 199 202 203 205 206
Appendices (held digitally by OSGF) Type 1 Soil Report: Jim Sawyer Virginia Working Landscapes report Boyd Pauley Collection Tree Inventory
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I NTRODUCTION Palimpsest: n. an object made or worked upon for one purpose and later reused for another.
Mountain, granite, creek, oak, fern: a few ingredients that make a landscape. Each has a different story spanning multiple scales. At Oak Spring, the story of rock begins nearly a billion years ago. The story of mountains reaches 30,000 feet. For oak the story begins in Asia. Each has a story of change in a complex, ever-moving landscape. Axe, stone, fence, path, mill: humans weave additional layers of story onto the landscape. Layers increase; the stories
become more interconnected. On the landscape, intersecting lines create complexity as one story is laid on top of another. To make a place special, it’s important to understand where the place has come from. To know your land means to uncover its best places and to learn the stories of its rocks, oaks, fences, and old paths. Every place is special, but the stories of some places are never revealed. So they remain uncelebrated. As Oak Spring’s next chapter unfolds it is critical to understand and document the stories, sites, and unique natural and cultural features the land offers. With millions of years of geological and biological evolution, and hundreds of
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years of intensive land use, these places will shape people's experiences, and ultimately define Oak Spring’s landscape in the minds and emotions of those who visit. It might seem at first glance that a small 262-acre property dominated by old horse pastures offers little to amaze. That was my impression when I first looked at the site through aerial imagery. I saw a sea of grass carved up by fences, a compound of buildings, and a couple of isolated patches of woods. When I arrived and walked the ground, pieces of the story began coming alive; I soon realized my error. Dozens of rock outcrops revealed Oak Spring has two primary rocks types: granites and diabase. When viewed in context of the Bull Run Mountains to the east and the Blue Ridge to the west, a story of volcanic instability emerged that reaches back a billion years. It’s this geological story that has ultimately shaped all of the ecological and cultural stories that follow. Everything from the base-rich natural communities to the importance of Upperville in the Civil War comes back to geology. Though I suspected the steep forest above Goose Creek might harbor interesting plants, I didn’t expect the history it revealed. The woods contain about six acres of old growth forest. White oaks germinated well before the American Revolution, and a post oak reaches back to the 1600s. The forest shows no signs of clearance, no logging for at least 75 years, and no fires. It does, however show signs of woodland grazing in historic times.
Of Oak Spring’s 638 open grown trees around the grounds and fields, several predate settlement. A blackgum reaches back possibly to the days before Virginia (that’s 1607, with the founding at Jamestown). At least one tree shows the landscape was open in the late 1700s, a possible indication of presettlement fires, or an indicator of the first European land clearance. Overall, 45 species of native trees and tall shrubs grow on just 262 acres of mostly grass. That is greater tree diversity than Yellowstone and Yosemite National Parks combined. With help from several expert birders, we cataloged a list of 92 bird species during 2017 at Oak Spring including rarities like the trumpeter swan and short-eared owl. Bald eagles nested in 2017 in a tall white pine across Goose Creek. In time, this list will surpass 100 species and could reach 150 species. The work of Virginia Working Landscapes revealed the diversity of insects, plants, and birds of these old horse fields. They also revealed that even fragmented horse country is used by American black bears (see photo in Part 3). Later, pieces from the cultural landscape fell into place and brought history out of books and placed it on the ground where it took place. Long-time gardener Boyd Pauley shared his remarkable American Indian artifact collection gathered from the once sprawling Mellon estate. It contains over 75 artifacts – projectile points and ax heads – that tell of story of occupation reaching back over 10,000 years.
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More recent stonework includes over two miles of rock walls from three vintages including the original walls (fences in practice) that date back to at least the early 1800s. A trip to the county land records office allowed me to successfully trace the deed back 200 years. At that time, the property is just a few transfers away from Thomas 6th Lord Fairfax, owner of the original 5.3-million acre Northern Neck Proprietary granted by King Charles to a loyal group of supporters during the English Civil Wars. Oak Spring lies on the edge of Fairfax’s Manor of Leeds – the private estate including the best land that he intended to keep for himself. The Fletcher family settled locally in 1790 (across the road) and a son, Robert, settled Oak Spring by the 1820s building a cabin in the exact footprint of the Mellon house. Robert Fletcher’s initials are carved into a block on the barn in 1833. It’s amazing the barn survived the Burning Raid of 1864 when Union soldiers torched barns and farms throughout this area. All these stories are shared within. Paul Mellon took ownership of the property in 1936. His father, Andrew, purchased the Rokeby Farm across the road in 1931 and Paul bought it from his mother shortly thereafter.
Too much should not be explained about a garden. Its greatest reality is not a reality, for a garden, hovering always in a state of becoming, sums up its own past and its future. –Rachel Mellon, 1965
Just as there is no substitute for original works of art, there is no substitute for the world of direct sensual experience. –Paul Mellon, 1967 At this time, upper Fauquier County was quickly transforming into a Hunt Country enclave for wealthy Americans. Paul would acquire more properties that would eventually amount to a contiguous 4000 acres. Rachel (Bunny) Mellon joined Paul in 1948 and their house was built in 1951 on the site of the Fletcher cabin. Soon after, stone walls were repurposed and rebuilt, five ponds were constructed, and for the rest of the 20th century horses and horticulture ruled. Thus Oak Spring begins the land’s own version 3.0 – its tenure of stewardship as the Oak Spring Garden Foundation. This follows the Fletcher family (1820s to 1920s), and the Mellon era (1930s to 2010s). With that change, it is a good time to step back and take stock.
PURPOSE, GOALS, SCOPE Considering all this richness embedded within the land (and not counting all that is embedded within the walls of the house, library, etc.), this project has three goals. First, is to document the background context, history, and stories that shaped the landscape we see today. This includes the
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geology, the history of the vegetation, and the human history of upper Fauquier County. The second element is to inventory and document what occurs at Oak Spring today. With a specific history shaping the past into the present, what occurs here today? The inventory includes trees, plants, ponds, Goose Creek, the cultural landscape, and an inventory of landscape change over the past two centuries. An inventory of the 20 best special places highlights the top wonders, scenic spots, ancient trees, and more. These sites will shape where people go and how they experience the landscape. The third piece of this project is to take the background context and the inventory and ask what Oak Spring should look like 100 years from now. How can Oak Spring use this raw material to serve the broader landscape and fulfill its mission? Reflecting on the values of the Oak Spring Garden Foundation and contemporary ideas of responsible land management, this document offers a path forward to make these ideas a reality. Management suggestions are scattered throughout Part 2, in the inventory section, and a synthesis of vegetation and trail planning is offered in Part 3.
LIMITATIONS A few limitations to the project are worth noting. The level of botanical detail in this document is moderate. I am primarily a forest ecologist, thus 200 acres of horse pastures were a bit mysterious to me. Much of the grassland diversity was
captured by Virginia Working Landscapes and is summarized. Additionally, one could spend a lifetime studying a patch of land like this. As the scope of the project expanded when new information and ideas emerged, it was necessary to at least attempt to remain focused. It’s easy to get lost in the minutia of Lord Fairfax, the history of the Fletchers, and the correct seed mix for native warm season grasses. Considering that, the project has depth and breadth and no management action will likely occur without additional research.
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SUMMARY Remarkable rock outcrops, ravines, ecological communities, and land use history combine to create a landscape of riches. Over 10,000 years of human history – from storied lithics, preCivil War stone fences, and the imprint of 80 years of Mellon stewardship – create something that is no less interesting than the grandest landscapes of the world. This document illuminates the unique palimpsest that is Oak Spring, with regard for its history, and an eye towards its future. ACKNOWLEDGMENTS Many people made this project possible. First thanks to Peter Crane who thought doing this was worthwhile. All of Oak Spring’s staff helped in some way, especially Clif Brown, Randy Embrey, Ronnie Caison, Jay Keys, Boyd Pauley, Max Smith, TJ Sherman, Marguerite Harden, and Andy Jackson. Special thanks to Elinor Crane for a plethora of tips, talks, and logistical help. A number of outside experts contributed a wealth of information including Eugene Scheel regional historian map maker and carto-celebrity, Tom Turner from the John Marshall Soil and Water Conservation District, Joe Rossetti from VA Division of Forestry, Jim Sawyer Fauquier County Soil Scientist, Wayne and Beth Gibbons, Charlotte Lorick from Virginia Working Landscapes, and Carole Nash, Professor of Archeology at JMU. Thanks to dedicated birders for their contributions: Doug Stotz, Mark Aronson, David and Nancy Hines, and Jennifer Randall. A special thanks to Autumn Von Plinsky for her outstanding artistic contributions. Finally, acknowledgement to Bunny Mellon for planting this seed now sprouting into the Oak Spring Garden Foundation. PRESETTLEMENT WHITE OAKS OVER 225 YEARS OLD, NEAR THE CEMETERY
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L ANDSCAPE C ONTEXT To understand Oak Spring, we first zoom out to view North America in its entirety. Oak Spring lies in the forests and farmlands of Virginia’s Piedmont. It’s situated just a short walk east of the Appalachian’s famed Blue Ridge – a narrow spine of land bounding the eastern edge of a broad mountain landscape. Equidistant from Florida’s tropical biome and the boreal forest of New England, Oak Spring lies in the heart of the Temperate Deciduous Forest. Keep the landscape in context: where are you?
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G EOGRAPHIC O VERVIEW When viewing the region around Oak Spring from high above, three features draw attention: i) the great series of parallel ridges and valleys that form the eastern Appalachian Mountains; ii) the deep green forests that cover the mountains and (though fragmented) the Piedmont; and iii) the heavily dissected rias of the Chesapeake region. Oak Spring sits in the midst of this geographic diversity. This section unpacks those details. Oak Spring is located in a broad valley between two low ridges. The valley – stretching north toward the Potomac River lowlands – is commonly referred to as the Loudoun Valley after the adjacent northern county. To the east, the Bull Run Mountains rise to 1,300 feet (400 meters) as a long narrow ridge 14 miles in length. Joined by a series of broken-up hills and ridges, the Bull Run Mountains gradually meld with Catoctin Mountain to the north, forming a topographic feature 60 miles (97 km) long. The ridge is split by the Potomac River at Point of Rocks, Maryland. To the west, Virginia’s famed Blue Ridge stands as the backbone of Virginia. The Blue Ridge is the dominant feature of the larger Blue Ridge Mountains. West of Oak Spring, the Blue Ridge reaches 2,176 feet at an unnamed highpoint. Land in this stretch of the Blue Ridge is publicly owned and managed as Sky Meadows State Park and the G. Richard Thompson State Wildlife Management Area. Shenandoah National Park begins less than 20 miles southwest.
P H YSIOGRAPH IC C O NTEXT Watershed
Goose Creek – Potomac River – Chesapeake Bay
Physiographic Region
Virginia Piedmont
Elevation Range
560 ft. to 371 ft. (171m to 113m)
Rock Types
Granitic Gneiss: 1.1 billion years Diabase (Metabasalt): 500 million years
Forest Region
Oak – Hickory
Soils
Ultisols
Annual Precipitation
43 inches (increasing)
Frost free days
185 (increasing)
County
Fauquier
At Paris, Virginia, Ashby Gap permits passage through the Blue Ridge. Nearly 10-miles to the south the larger Manassas Gap bisects the Blue Ridge carrying with it Interstate 66, several smaller roads, and a railroad. Both of these gaps pass into the Shenandoah Valley. At 887 feet, Manassas Gap forms the lowest elevation break in the Virginia’s Blue Ridge. The less developed Ashby Gap stands higher at 1,027 feet. These gaps, among others in the ridges of Virginia, have served as
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dispersal corridors for flora, fauna, and people for thousands of years. Gaps played key roles in the Civil War. As the Blue Ridge trends north toward Harper’s Ferry at the Potomac River, a parallel sub-ridge emerges to the east. This is Short Hill Mountain, which continues north as South Mountain, a significant feature in Maryland and Pennsylvania. Between the Blue Ridge and Bull Run Mountains, to the south of Oak Spring, lie a series of north-south trending ridges appropriately called the Broken Hills. These include the Watery Mountains (1,337 feet), the Pignut Mountains (1,100 feet), and Big Cobbler Mountain (1,630 feet), among others. The range occurs south of Interstate 66 and Marshall, Virginia, and forms the upper and southern reaches of the Goose Creek watershed. The Bull Run Mountains, Blue Ridge, and Broken Hills are visible from several locations at Oak Spring. Oak Spring lies in the Goose Creek watershed – the principle drainage for Loudoun and upper Fauquier County. Goose Creek rises at Manassas Gap, at an elevation of 1,040 feet, and quickly falls 600 feet over 10 miles. It passes through Oak Spring at an elevation of 400 feet and follows a low-gradient, meandering course to the Potomac River. It cuts through the Bull Run – Catoctin Ridge at Oatlands, Virginia, before its final push to the Potomac River east of Leesburg. Though the creek does not pass though urban areas, it does parallel Interstate 66 for over 5 miles at its headwaters.
Goose Creek is a fourth order, low gradient stream with long stretches of sandy bottom. The main stem is approximately 55 miles, and the watershed encompasses ~300 square miles (800 square km) of farm, fields, forest. Goose Creek hydrology and other characteristics are described in its own section. The Potomac is the region’s principle river and Goose Creek and Oak Spring lie within its watershed. While the Potomac has a rich natural and human history and vast and varied catchment area, it is the Fall Line that is arguably its most important bio-cultural feature. Here the Piedmont meets the Coastal Plain and the ensuing knickpoint creates rapids at Little Falls, followed slightly farther upstream by Great Falls. This point marks the uppermost reach of tidal influence, creates a barrier for aquatic organisms, and limits human travel upstream. On nearly every Piedmont river, a city lies at the Fall Line. Washington DC fills that niche on the Potomac. Beyond it, the Potomac empties into Chesapeake Bay. The variable topography of the northern Virginia Piedmont and Blue Ridge shaped the unique history of the region. People have used the gaps and rivers for thousands of years. This will be more fully explored in the history sections.
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SHADED RELIEF MAP OF THE MID-ATLANTIC REGION centered on Oak Spring (yellow star). Note the broad Loudoun Valley, the Blue Ridge, and the Chesapeake Bay region.
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GOOGLE TERRAIN MAP OF NORTHERN VIRGINIA. Oak Spring, located in the Loudoun Valley, between the Blue Ridge Mountains, Bull Run Mountains and the Broken Hills, is noted with a with yellow star.
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BROKEN HILLS OAK SPRING REGIONAL TOPOGRAPHY, roads, and towns. Landforms mentioned in the text are labeled.
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Physiographic Province A physiographic province is a region of similar geomorphology, and typically, similar geologic origins. Virginia contains five physiographic provinces – more provinces than is typical for most states, and a remarkable amount of topographic diversity. Oak Spring lies in the Piedmont province – the largest province in Virginia.
The human, or cultural landscape lies untidily on top of this. It may seem simple, but the Blue Ridge is forested because its slopes and soils do not lend themselves to agriculture. Instead, agriculture and urban areas occur in the valleys, which often have richer soils from softer rocks. Cities also occur at the intersection of the Fall Line and rivers. This document brings these concepts down to the 260 acres of Oak Spring.
PHYSIOGRAPHIC MAP OF VIRGINIA: Key: AP: Appalachian Plateau province; RV, GV, M: Valley and Ridge province; nBR, sBR: Blue Ridge province; F, ML, OP: Piedmont province; CU, CL, BM: Coastal Plain province. Oak Spring is located in the Foothills subprovince of the Piedmont shown with the red star. Oak Spring (red star) lies in close proximity to most of the state’s subprovinces.
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G EOLOGY OF O AK S PRING The geologic foundation shapes and drives all other landscape conditions. Ecosystems and community types are driven by geology. The ways humans create habitat from the landscape with agriculture, forest, and urban areas, is a result of geology. The particular geology of Oak Spring and Fauquier County could fill volumes. This brief description is intended to provide background context for everything that follows, and provide interpretive value for the geological features found at Oak Spring.
Foundations Two critical background elements are needed before any understanding of geology can occur. First, geologists describe three basic rock types: igneous, sedimentary, and metamorphic. Igneous rocks began as molten lava beneath the surface of the earth. Igneous rocks may cool above the surface as a volcano (extrusive igneous rocks), or they may cool and harden deep below the surface (intrusive igneous rocks). Granite is an intrusive igneous rock, a form of which is common Oak Spring. Sedimentary rocks are composed of eroded material, deposited and later coalesced into rock. Sandstone (derived from deposited sand) and limestone (from deposited marine shells) are sedimentary rocks. Metamorphic rocks typically begin as igneous or sedimentary rocks, but then deep below the surface heat and pressure alter the rock enough to recrystallize it. Metamorphic rocks may be “cooked� or squished multiple times and/or to varying degrees. Oak Spring contains old, hard, metamorphic rocks.
Oak Spring Geology: Vocabulary METAGRANITE: 1.1 billion year old metamorphosed granites underlying much of northern Virginia and exposed at Oak Spring.
DIABASE: A volcanic rock compositionally the same as basalt, but with coarser texture due to slower cooling in deep dikes.
DIKE: A vein through which molten rock intrudes from depth sometimes reaching the surface.
CATOCTIN FORMATION: Massive basalt flows in the northern Blue Ridge region 570 million years ago.
BLUE RIDGE ANTICLINORIUM: An arced fold with many minor folds stretching from the Bull Run Mountains to the Blue Ridge.
FALL LINE: Geologic line where Piedmont meets Coastal Plain. Most rivers have a rapids or falls and a city at this location.
IAPETUS OCEAN: An ocean that formed as the supercontinent Rodinia rifted apart 550 million years ago.
PANGAEA: Ancient super-continent at 300 million years that gave rise to the Appalachian Mountains.
SAPROLITE: Chemically weathered rocks between the upper soil layers and bedrock; piedmont is composed of much saprolite.
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GEOLOGY UNFOLDS ALONG PEACH TREE LANE: the ancient Bull Run Mountains rise in the distance showcasing the eastern edge of the 570 million year old Catoctin basalt flows; billion year old granite at right crops out with vegetation adapted to dry, acidic sites; an original stone fence composed of diabase and granite field stone collected onsite.
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The second background process needed to understand geology is plate tectonics. The theory posits that the Earth’s surface is broken up into a system of plates and these shallow lithic rafts float on a molten mantle. Slowly, through convection processes, the plates move around, coalescing, subducting, scraping, and bumping into one another. This process gives rise to volcanoes, mountains, earthquakes, and even the continents and oceans themselves. Plate tectonics is the driver that creates and erodes rocks to form igneous, sedimentary, and metamorphic rock types. Plate tectonics is the primary factor creating the Blue Ridge, the physiographic provinces, and the landscape of Virginia more broadly. With a very basic geological background behind us, we can look at the specific events that created Oak Spring. Oak Spring’s features have large geologic controls – plate tectonics, volcanism, mountain building, and erosion.
Granite and Greenstone Oak Spring contains two primary rock types. Both are found over a broad regional area, but crop out at Oak Spring in unpredictable ways (J. Sawyer, personal communication). The older rock(s) is a metagranite or granitic gneiss. There are several specific rock types regionally described as a metamorphosed granite, or granitic gneiss. Without special analysis it’s not possible to know which of the lot occurs at Oak Spring (and there could be more than one). Nonetheless, all of the regional metagranites are similarly aged at 1.1 billion years. Despite their age, and the intense conditions following two periods of continental collision
causing recrystallization, when seen on the ground or in a stone wall at Oak Spring, the rocks still look like brightly colored granite. Sometimes the rock has bands showing its metamorphic history. Oak Spring’s second rock type is a 570 million year old metadiabase, commonly called greenstone. It’s the more common rock found in outcrops and stone walls at Oak Spring, but the less common rock regionally. Diabase is a volcanic rock compositionally similar to basalt. But because it cooled more slowly, the crystals and texture are coarser. At Oak Spring and the Loudoun Valley, diabase occurs as dikes, or veins intruded through the older granitic rocks. The diabase has been slightly metamorphosed resulting in metadiabase. A fine-scale geological map has not been produced for Fauquier County; however, an excellent, highly detailed map has been done for Loudoun County (Southworth et al. 2006), just 1.5 miles (2.4km) north of Oak Spring. Below is a clip from that map with Oak Spring geo-referenced to its true position slightly south to give an idea of the geological diversity and complexity of the local landscape. Dominant rock type descriptions are included. Considering what is found on the ground, it is expected that the geology at Oak Spring follows this pattern. However, Oak Spring seems to have broader diabase dikes than occur farther north.
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Ylg: Layered granitic gneiss—White, gray, or pink, medium- to fine-grained, well-layered garnetbiotite-plagioclase-quartz-microcline gneiss. Layering, 0.04 to 0.4 in thick; garnets up to 0.4 in. in diameter scattered throughout rock. Complex structures in outcrop include folded layering and swirly, migmatitic texture. Relation to other granitic units unknown.
Ypg: Porphyroblastic metagranite—Yellowish-brownweathering, medium- to coarse-grained garnetbiotite-plagioclase-quartz-microcline metagranite. Characterized by megacrysts of orange to pink microcline or microcline-rich aggregates that are deformed into rounded ovoids 0.4 to 1.2 in. in diameter; garnet, biotite, plagioclase, opaques, and distinctive clots of blue quartz occur interstitially.
Ym:
Marshall Metagranite—Pink, medium-grained, weakly to moderately well-foliated and (or) lineated biotite-plagioclase-quartz-microcline metagranite. Biotite content ranges from 10 to 15 percent. Layering locally produced by veins of pink pegmatite parallel to foliation. Resembles biotite granite gneiss (Ybg) in outcrop.
Ygt: GEOLOGICAL MAP OF LOUDOUN COUNTY SHOWING OAK SPRING: Oak Spring is georeferenced to its relative location (located on the scale bar). Pink dots are outcrops of granitic rocks and gray dots are metadiabase outcrops. Selected rock descriptions provided below and right. No geological map to this scale is available for Fauquier County. See Inventory Section for a detailed map of the outcrops at Oak Spring.
Zmd:
Metadiabase dikes (Late Proterozoic)—Dark-greenish-gray, fine- to medium-grained, massive to schistose metadiabase (greenstone) composed predominantly of chlorite, epidote, albite, and actinolite. Coarse-grained and porphyritic metadiabase dikes have stubby, 0.08- to 0.16-in-long actinolite pseudomorphs after clinopyroxene that produce distinctive nubbly texture and are shown by a pattern north of Taylorstown. Dikes range in thickness from a few inches up to 164 ft thick. Compositionally similar to metabasalt of the Catoctin Formation.
Garnetiferous leucocratic metagranite—White, medium- to mediumfine-grained, massive to moderately foliated garnet-plagioclasequartzmicrocline metagranite. Identical to Yg except for the presence of irregularly distributed almandine crystals.
Yml:
Pink leucocratic metagranite—Pink, medium- to medium-fine-grained, massive to moderately foliated plagioclase-quartz-microcline metagranite. Biotite content ranges from 0 to 10 percent. Foliation defined by flattened quartz and feldspar grains and local thin biotite-rich layers.
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Process: Continental Collisions The geologic story of Oak Spring begins 1.2 billion years ago with granitic rocks deep beneath the Earth’s surface. At this time, two proto-continents coalesced into the ancient supercontinent Rodinia. The collision spawned the Grenville Orogeny – a mountain building event in what is now eastern North America. Heat and pressure caused by the collision “cooked” the granitic rocks recrystallizing them into the metamorphic granites seen at Oak Spring. The rocks recrystallized into something still resembling granite, but with a different crystal structure. Mountains rose from uplift, and erosion concurrently tore them down. The Blue Ridge is one of a few places where Grenville rocks are exposed. Rodinia didn’t last long. By 800 million years ago it split apart approximately at the margin where it joined. Eroded sediment was deposited east and west of the crest, some of which can be seen in the eastern Virginia Piedmont (Frye 1995). The tearing apart of Rodinia thinned the Earth’s crust in the rift zone allowing molten material to break through and flow across the surface. The Catoctin Formation, a massive surficial basalt flow, is dated to 570 million years ago. It spread approximately 30,000 cubic kilometers of basalt across an area from southern Pennsylvania to central Virginia over a few million years (Johnson and Baily 2014). Only very primitive organisms lived at the time and nothing significant on land. The Catoctin Formation erupted through the hard metagranitic rocks via a system of dikes. As the rifting caused
thinning of the Earth’s crust, the basalt pushed through weaknesses via these dikes. The diabase outcrops at Oak Spring are the ancient vertical feeder dikes that facilitated the Catoctin basalt flow (Leo 1990). Because dikes penetrate deeper underground than the surficial basalt flow, the molten rock cooled more slowly. Slow cooling allows crystals to grow larger and the texture is therefore coarser. But ultimately the diabase at Oak Spring is the same composition and age as the Catoctin basalt. The rock is commonly called “metabasalt” and colloquially called “greenstone.” As the basalt was laid down, Rodinia continued ripping apart. The newly formed basin filled with seawater as the new continents spread apart and a new ocean was born. Called the Iapetus Ocean, it is considered a precursor to the Atlantic. For the next 200 million years (520-320 Ma), the shallow sea covering the basalt flow accumulated sediments from deposition eroding off the surrounding continents. Sands, gravels, muck, and the decaying bodies of rapidly diversifying marine organisms built up in great quantities. These layers eventually coalesced into sandstone, limestone, and other sedimentary rocks. The Cambrian – Ordovician sedimentary sequence occurs at the surface on the west side of the Blue Ridge in the Shenandoah Valley. But what happened to the sedimentary sequence on the east side of Blue Ridge at Oak Spring? By 350 million years ago pressure built as a new continental collision began. Laurasia and Gondwana closed in on each other and in the process
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closed the Iapetus Ocean. The pressures from the collision caused folds and thrust faulting in the layers of rocks described above. A broad, arching fold, called an anticline, formed between 350 and 320 million yeas ago in the general area of the basalt flow. Within it, a number of smaller complex folds also formed, making it an anticlinorium (a complex series of anticlines embedded into a larger one). The Blue Ridge Anticlinorium stretches from the basalt ridge of the Bull Run Mountains to the basalt cap on the Blue Ridge, and from Pennsylvania to central Virginia. The uplifted anticline was breached by erosion, which subsequently stripped away all the overlying layers. Not only are the sedimentary layers gone – today still exposed in the Shenandoah Valley – but so also are the Catoctin Basalts over the Blue Ridge Anticlinorium. Today, then, old basement rocks of metamorphosed granites, and the feeder dikes of basalt, are exposed in the Loudoun Valley – the geographic term for the geologic feature of the Blue Ridge Anticlinorium. Uplift causes erosion; younger material is stripped away and the old layers are left exposed. The compressional forces that created the anticline also created the Appalachian Mountains and the supercontinent Pangaea. At around 300 million years ago, as the continental collision peaked, the Blue Ridge was thrust west, over the top of the younger sedimentary rocks now lining the Shenandoah Valley. Today two sets of stacked sedimentary rock layers lie in that valley, with the older Blue Ridge granites and basalts
resting on top. In some areas, 20 miles of rock cover the Grenville basement rocks (Frye 1995). The pressures of the collision metamorphosed many rock layers. The Catoctin Basalt became a metabasalt. And Oak Spring’s diabase dikes were altered into metadiabase – the same mineral composition cooked into a new crystal structure. As continents do, soon after the collision that formed Pangaea, it rifted apart. The Atlantic Ocean formed and for the next 200 million years, erosion has been the driving force. It stripped the mountains down to their roots, and deposited the spoils along the edge of the continent forming the Coastal Plain of Virginia, and beyond. What’s left are the very hard “roots” of the old mountains. The Appalachians once reached heights equivalent to the Himalaya. Today only those hard, erosion-resistant, metamorphic basement rocks remain. One day the Himalaya will also be eroded to a set of low hills and crags. Though Oak Spring contains over 75 rock outcroppings on its 262 acres, in general, rocks of the Piedmont are mostly buried beneath 100 feet of saprolite – a mantle of chemically weathered rock grading down to partially weathered rock then to unaltered bedrock (Frye 1995). Nonetheless, geology has played a critical role in the region’s history considering the effect rock parent material has on soil fertility, productivity, topography, stone walls (over two miles worth), and more. Geology, ultimately, drives everything.
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GEOLOGICAL TIMELINE TO OAK SPRING AND SURROUNDING AREAS. Rocks and formations specific to Oak Spring shown in colored boxes at right. Years BP are averaged based on a variety of sources; several are listed in the text. Years BP
Age
<1,000 years
Anthropocene
<65 Ma
Tertiary
<200 Ma
Jurassic and later
200 Ma
Late Triassic
290 Ma
Permian
335-260 Ma 520-350 Ma 550-400 Ma
Carboniferous to Permian Cambrian to Carboniferous Cambrian to Devonian
Key geologic events shaping Northern Virginia Humans cause rapid increase in soil erosion, chemical alteration of soil, and topographic modification Deposition forms Coastal Plain; Marine transgressions oscillate into Piedmont; Oak Spring set with metagranites, metadiabase dikes, and Goose Creek; erosion every day Erosion of Appalachian Mountains and Blue Ridge Anticlinorium removes sedimentary rocks and eventually most of the Catoctin metabasalts Rifting splits Pangaea; sea water fills and the Atlantic Ocean is born; erosion takes over as driving geological force on the Appalachian Mountains Blue Ridge rocks thrust over younger sedimentary rocks of the Valley Blue Ridge and Ridge province; Blue Ridge Anticlinorium forms under pressure Anticlinorium from tectonic collision Iapetus closes as Gondwana and Laurasia coalesce to form Pangaea; Alleghanian Orogeny forms massive Appalachian Mountains Sediments of sand, muck, and marine organisms are deposited on Catoctin Basalt in the Iapetus Ocean; sediments later form limestone, quartz sandstone, and other rocks Iapetus Ocean forms as Atlantic precursor when Rodinia splits apart; ocean water floods freshly laid Catoctin basalts Catoctin basalts flow across the surface via dikes through granites as Diabase/Basalt Rodinia rifts apart; Oak Spring’s metadiabase dikes formed at this dikes time
570 Ma
Late Proterozoic
800-650 Ma
Late Proterozoic
Rodinia breaks up, rifting near the eastern edge of today’s North America
1,000-500 Ma
Late Proterozoic
Erosion of uplifted mountains wears them down to rolling hills
Middle Proterozoic Middle Proterozoic
Granitic basement rocks form; includes granitic gneiss (Marshall) at Metagranites Oak Spring; among oldest rocks in Virginia and eastern N. America and Gneiss Supercontinent Rodinia forms; colliding continents spawn Grenville Orogeny and huge mountain building along eastern edge of today’s North America
1,100 Ma 1,250-1,000 Ma
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Geology References: Frey, K. 1995. Roadside Geology of Virginia. Mountain Press. Johnson, A. and C. Baily. 2014. Glimpses of the Past: The Catoctin Formations â&#x20AC;&#x201C; Virginia is for Lavas. College of William and Mary. Accessed 24 July 2017: http://geology.wm.edu/bailey/CatoctinFormation.pdf Leo, G. 1990. Geologic Map of the northern part of the Rectortown Quadrangle, Virginia. Open File Report 90-639. Nelson, A. 1997. Geology of the Upperville 7.5- Minute Quadrangle, Fauquier and Loudoun Counties, Virginia. Open File Report 97-708. Southworth, S. et al. 2006. Geologic Map of Loudoun County, Virginia. United States Geological Survey. Southworth, S. et al. 2009. Geology of the Shenandoah National Park Region. 39th annual Virginia Geological Field Conference. Accessed 24 July 2017: http://csmgeo.csm.jmu.edu/geollab/eaton/web/eaton_files/Publicat ions/vgfc2009.pdf
Red oak Quercus rubra
24
C LIMATE Virginia’s climate is as diverse as its landscape. Portions of the state abut the ocean, others showcase lofty mountains, and others lie in protected valleys. The Köppen classification system divides Virginia into three zones with Piedmont Virginia occurring in the Humid Subtropical zone. Virginia is at the northern extent of this zone and it includes the remaining southeastern US. Other regions globally in this zone include northern Italy, the Balkans and Black Sea region, eastern China, eastern Australia, and the South American Pampas. Virginia is not as snowy and frigid as New England, nor as muggy and wet as Florida. Virginia’s climate is often described as the “Goldilocks” climate: just right. Climate, of course, expresses itself in the local ecology. Paired with substrate and disturbance, climate determines natural
communities. It also determines, in part, what is possible with regards to Oak Spring’s restoration and ornamental plantings.
Local Drivers The climate at Oak Spring occurs as a result of wide ranging global geographic patterns. Local factors contributing to Piedmont climate include the: • • •
Proximity to the Atlantic and the Gulf Stream Appalachian and Blue Ridge Mountains Network of coastal valleys, which guide airflow and force precipitation.
The Atlantic is a great moderator of climate. It cools lands in summer, and warms them in winter. Of greater importance inland, however, are warm, moist air masses that churn out of
25
the tropics and travel up the coast. In summer and fall these storms bring rain. In winter they can bring heavy snows.
experiences thunderstorms one out of every three days in July.
The Appalachian and Blue Ridge Mountains cause increased local precipitation as moisture-laden air is forced upward. When systems move inland from the Atlantic, the east slopes are most affected (e.g. Oak Spring). When systems originate from the west, the lee-side of the mountains remains drier (e.g. Oak Spring). The mountains themselves are typically wettest and the valleys between them, such as Shenandoah, are driest. Receiving just 33 inches of precipitation annually, areas of the Shenandoah are the driest in the state.
A southerly airflow brings moisture up Virginiaâ&#x20AC;&#x2122;s coastal regions and into the Piedmont and eastern mountains. The Gulf Stream, which begins as tropical easterlies at low latitudes, carries warm, moist, tropical air west, then north, shifting northeast as they pass Virginia. Depending on the time of year, these storms have varying intensities and effects.
Virginiaâ&#x20AC;&#x2122;s valleys spill out in all directions and provide conduits for air masses to flow though. Atlantic storms track up coastal valleys, dropping precipitation as elevations increase up valley. They also provide conduits for descending air masses moving from the west. These tend to be dry as descending air isnâ&#x20AC;&#x2122;t conducive to rainfall.
Patterns and Process Weather systems affecting the Piedmont typically flow from the west or from the south. When storms track from the west, they cross the mountains and lose moisture before reaching the Piedmont. Sometimes storms track up the Ohio Valley and dump considerable moisture into northern Virginia. Western storms often move parallel to the mountains or the coast. Either way, once storms approach the coast, the Gulf Stream forces them northeast. Thunderstorms associated with warm moist tropical air masses move in from the west. Virginia
Tropical systems can reach hurricane strength from June to November but occur most commonly in August and September. Hurricane Camille in 1969 dumped 33 inches of rain on some east slope areas of the Blue Ridge. These are the most intense weather events in Virginia. Ecologically, high winds and flooding can cause massive-scale disturbance. Streams and rivers reach their highest stages during hurricanes and tropical depressions. Since 2000, a named storm has made landfall (typically weakened to a tropical depression) in Virginia almost every year. Large rain events from these storms are the primary driver of stream channel formation and alteration, including on Goose Creek. Winter storms tend to track west to northeast but also occur as a result of warm systems from the south. The foothills and eastern slopes of the Blue Ridge take the brunt of these storms. The heaviest snows fall when warm moisture-laden storms track out of the Gulf and up the East Coast, and collide with cold air masses from Canada. These dumps bring significant snows to the Blue Ridge, but it is the high ranges
26
of West Virginia often set single storm snowfall records as a result of these storms. The Piedmont region averages less than one major coastal snowstorm each year.
Clim ate statistics for O ak Spring based on regional data Annual Precipitation
43 inches
Since Oak Spring does not have a weather station (OSGF should consider one) I looked at data (1980-2016) from three surrounding cities to triangulate the climate normal for Oak Spring: Winchester, Leesburg, and Warrenton. All three cities (each ~15 miles away) are close climate approximations to each other and presumably to Oak Spring. I also looked at data from Mount Weather and Marshall where those data were available. The table at right outlines Upperville’s climate estimated from these nearby weather stations.
Average temperature
54°F
Peak of Summer Heat
July 21
Peak of Winter Cold
January 29
Average July high
88°F
Average January Low
24°F
Average Snowfall
22 inches (Marshall, VA)
Wind origins
~40% W; ~20% S; ~25% N
Windiest period
February-March (Ave. 4 mph)
Changing Climate
Least Windy period
July-August (Ave. 2 mph)
Observations from the National Oceanic and Atmospheric Administration (NOAA) indicate Virginia’s annual temperature has increased by 1.1°F (0.6°C) since 1895. Projections suggest a 2.0°C increase is likely over the next 50 to 100 years.
Last spring frost
April 17
First fall frost
November 1
Growing season
197 days
Cloudiest Month
January (52% overcast)
Precipitation in Virginia has increased from an average of 42 inches/year to a statewide average just over 44 inches, since 1895, representing a 5% increase. Some parts of the state have seen 10% increase. More precipitation falls in large events, and more falls during winter than had previously. Snowfall is decreasing and winter rainfall is increasing. A section in Part 3 outlines ways Oak Spring can adapt future plantings to a changing climate as warmer temperatures and increased precipitation affects vegetation and Goose Creek.
Sunniest Month
September (65% clear)
Driest Month
February (2.8 inches)
Wettest Month(s)
May (4.3 inches) Sept. (4.1 in.)
Record High
104°F (Marshall, VA 8/18/88)
Record Low
-11°F (Marshall, VA 1/16/72)
Climate by the Numbers
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Climate References Hayden, B. and P. Michaels. Virginiaâ&#x20AC;&#x2122;s Climate. University of Virginia Climatology Office. Accessed September 21, 2017. http://climate.virginia.edu/index.htm Climate data from: www.weatherspark.com www.usclimatedata.com www.intellicast.com Bradley, R., et al. 2016. State Climate Report: Virginia. Climate System Research Center, University Massachusetts Amherst. https://www.geo.umass.edu/climate/stateClimateReports/VA_Clima teReport_CSRC.pdf
Black-eyed Susan Rudbeckia hirta
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T EMPERATE D ECIDUOUS F OREST The forest of eastern North America is the continent’s unsung treasure. It’s vast, it’s diverse, it’s beautiful, and it contains the rich biological history of the past 100 million years. All too often the eastern forest remains unseen, standing only as backdrop as we find excitement in the grandeur of the West, or the remote North, or the mega-diverse tropics. But with its rich tree and herbaceous flora, bird and insect richness, and unparalleled aquatic diversity, the eastern deciduous forest is one of the world’s remarkable natural areas. The temperate deciduous forest is Earth’s mesic forest: not too cold, not too hot, not too dry, and not too wet. Though terrestrial communities dominated by tall woody plants appeared as far back as Late Devonian times (360 Ma), we will begin with organisms that resemble those we see today at Oak Spring.
Deep Time Stepping back 80 million years, we arrive in a world where the precursor to North America’s eastern forest dominated the northern hemisphere. Angiosperms had been around for over 40 million years at this time, and fossil relatives of oaks, maples, and other eastern trees are found in rocks of Late Cretaceous age in Alaska and Siberia. From there the forest stretched east and west into Asia, Europe, and North America. Many plant groups we find today grew and radiated during that time. The world was warm, diverse, and wild. While pines and other conifers appear by 150 Ma, most tree families found in today’s temperate deciduous forest were beginning to appear by 80 Ma in the Late Cretaceous. These include Ulmaceae, Fagaceae, Betulaceae, and Juglandaceae among others. In some cases, the oldest families of temperate flora are first found in tropical-origin fossils between 20°N and
29
20°S latitude. A polar temperate forest biome became established around 60 Ma at 70°N latitude and included the genera Acer, Alnus, Betula, Juglans, Populus, and Quercus as well as deciduous conifers Ginkgo, Larix, and Metasequoia. An explanation for the deciduous habit trees has been proposed many times under many mechanisms. Axelrod (1966) proposed that the trait first evolved under winter-dry conditions. Wolfe (1987) suggested deciduousness evolved in situ in the high northern latitudes as a winter-dark strategy even though temperatures remained above freezing. Both of these hypotheses suggest cold-hardy deciduousness as an inadvertent adaptation to some other causation for losing leaves (dark, or dry). It is believed deciduousness in woody plants has evolved more times than other convergent plant characteristics. Distantly related groups such as oaks and maples, for example, are believed to have evolved deciduousness independently in an example of convergent evolution (Edwards et al. 2017). Nonetheless, the trait proved adaptive and allowed a huge array of taxa to survive the increasingly cold climate that has prevailed since mid-Tertiary times. In winter the temperate forest goes into dormancy. The process involves three steps: cessation of growth; abscission of leaves from trees; and biochemical processes that protect the tree from drought, starvation, and freezing temperatures. Whatever the evolutionary path taken to achieve this
remarkable process of adaptation, it happened in multiple taxa at multiple times. During Eocene times, about 50-55 million years ago, the planet reached a thermal maximum. Earth was about 14°C (25°F) warmer than today. Early progenitors of today’s temperate flora covered the high arctic latitudes. For reasons that are not entirely clear, at 52 Ma the warmth ended and the planet began to steadily cool. At 45 Ma tectonic forces caused the final rift in the North Atlantic, separating North America from Europe. With that, the flora was split; two trajectories of temperate deciduous ecosystems were set in place. There may have been some biological exchange, however, as late as 15-10 Ma, as recently emerged Iceland received temperate deciduous flora from Europe or North America (Grimmson 2007). At about 35 million years ago, planetary events involving the atmosphere, tectonics, and ocean currents began cooling Earth more quickly. Cooling initiated at the poles, with icecover occurring for the first time on Antarctica, and slowly pushing toward the equator. Subsequently, warmth-loving forests that once occupied the far north were constrained to the mid-latitudes. A cooling climate separated the Asian and North American floras as each was pushed south, increasingly separated by the vast Pacific Ocean. The forest zone that once spanned around the world was divided into three areas: Europe, East Asia, and the mid-latitudes of North America.
30
In Miocene times (23 to 5 Ma), climate was 3°C to 6°C warmer than the late Holocene average. Temperate deciduous forest occurred throughout present day southern Canada and the Great Lakes region (Lohmann et al. 2015). Global cooling continued through Pliocene times and into the Pleistocene Epoch as cooling climate continued to push the temperate forest farther south. Nonetheless, at 10 Ma Alaska still contained communities of Carya, Ostrya, Juglans, Corylus, and Quercus – the tree flora of Oak Spring. Most genera occurred in Iceland at the same time. By the Middle Pliocene (~3 Ma) temperate deciduous forest covered most of present day New England, Quebec, and Ontario (Salzman et al. 2008). During this time the Sierra Nevada, Rocky Mountains, and other ranges of western North America (among other ranges globally) were in the final stages of their present uplift. As such, the west dried out, and moisture dependent broadleaved trees settled into eastern North America where climate was favorable. The ideal conditions for temperate forests found in North America’s southeast quadrant include: strong seasonality regulated by temperature more than precipitation; warm, moist summers; and winter lows above -40°F (-40°C). The most recent 2-million years have brought greater instability to the eastern forest. As glacial and interglacial pulses have waxed and waned in northern North America, periods of cold forced the broad-leaved deciduous forest south, confining it at times to refugia along the Gulf Coast, south Florida, and the mountains of Mexico. As climate warmed, the forest spread back north.
Settling In At the height of the last glacial period, 18,000 years ago, Virginia was dominated by spruce and pine forests not unlike northern Canada today. Boreal conditions dominated for another 3,000 years before vegetation responded to climate warming and oaks began overtaking spruce. Over a period of 8,000 years, warming temperatures facilitated the arrival of temperate forests in Virginia. As we will see, humans also had a hand in shaping the composition and structure of the forest. Because Virginia was not glaciated, it contains only two natural lakes: Mountain Lake in Giles County, and Drummond Lake, part of the Great Dismal Swamp near the coast. Mountain Lake is a high elevation lake in Virginia’s Appalachian Mountains. The lake has a curious geology, leading to periodic draining. A sediment core extracted by Cawley et al. (2001), revealed 6,000 years of tree pollen lumped as “hardwoods” and “pine”. Similarly, the Great Dismal Swamp has received limited study, but the record nonetheless, shows that since 12,000 years BP vegetation has moved from 1) pine-spruce; 2) beech-hemlock-birch; 3) oakhickory; to 4) cypress-gum which has been in place for 3,500 years (Levy 1991). Thus late Pleistocene and Holocene pollen in Virginia offers little for reconstructing forest dynamics. It’s important to consider several converging factors with regard to ecosystem development over the past 15,000 years. Sea level rise, loss of megafauna, increased hurricane frequency, and the arrival of Native Americas all affected the rate of change as well as the result.
31
BIOLOGICAL TIMELINE to eastern North America’s Temperate Deciduous Forest. Years BP
Age
Key events shaping the Eastern Deciduous Forest Virginia lies in the heart of the Temperate Deciduous Forest. Oak Spring is dominated by Quercus, Carya, Juglans, Nyssa, among others. Widespread forest clearance, local flora and fauna extinctions, and the introduction of European and Asian species dominate the next 400 years. Height of recent glacial maximum. Virginia dominated by jack pine and spruce woodlands. Humans arrive in a few thousand years and begin shaping the temperate forest through hunting animals and forest burning. Warming allows temperate forest to expand from refugia along Gulf Coast. Great American Interchange exchanges flora and fauna as N. and S. America dock. Ice expands considerably in northern latitudes as glacial cycles begin for next 3 million years, pushing forests south. After a period of relative warmth, earth’s cooling trend continues. Grasses and grasslands continue to expand. Western North American mountains rise, drying the west and restricting temperate deciduous forest to eastern North America.
400 years
Holocene
18 Ky
Pleistocene
3 Ma
Pliocene
15 Ma
Miocene
32 Ma
Eocene
35 Ma
Eocene
36 Ma
Eocene
45 Ma
Eocene
52 Ma
Eocene
Earth begins a gradual cooling that lasts until present time.
Paleocene – Eocene Cretaceous – Paleocene
Warmest period in earth’s recent history (<100 Ma). Temperate deciduous flora occurs in high northern latitudes including vegetation (genera) found today at Oak Spring. Extinction event from Chicxulub impact caused temporary winter conditions (and faunal extinction). Grasses expand and angiosperms in general continue to diversify. Cold Temperate hardwood trees become part of the global flora: early relatives of Alnus, Betula, Corylus, Nyssa, Salix, Quercus. Warm Temperate hardwoods form an important component of subtropical forests: Carya, Liquidambar, Cercidiphyllum, Glyptostobus, and Sequoia. Sea level is 300m higher than today; lands low lying; CO2 1620ppm; pines and other gymnosperms established; angiosperms recently established and diversifying.
55-50 Ma 66 Ma 100-70Ma
Late Cretaceous
>100 Ma
Cretaceous
Earth cools dramatically as Drake Passage opens and isolates Antarctica. Temperate forest begins steady southward shift out of the Arctic to middle latitudes. Chesapeake Bay impact crater creates a catastrophic tsunami that reaches the Blue Ridge Mountains. Virginia then covered in Tropical Forest. Event reshapes regional drainage network. North American high latitudes contain contemporary temperate genera: Acer, Betula, Carya, Castanea, Fagus, Juglans, Liquidambar, Platanus, Prunus, Quercus, and Ulmus. Contiguous flora of North America and Eurasia significantly disrupted as North Atlantic rifting isolates the two temperate forests.
32
As shown by pollen studies elsewhere in the southeast, temperate deciduous species including Quercus, Carya, Liquidambar, Castanea (and their complements), found refuge along the Gulf Coast south of 34° N (Delcourt 2002). River terraces and bluffs provided microsites for species forming an “Ice-age archipelago of island refuges” (Delcourt 2002). These small sites each harbored a different suite of species that, once climate allowed, spread to fill the region formerly covered in spruce-jack pine-fir forests, including Virginia.
PERCENT OF TREES IN THE NORTHERN VIRGINIA PIEDMONT DURING POST-GLACIAL PERIODS (Ky BP= thousand years before present) following the Last Glacial Maximum. After maps by
In repopulating the continent with thousands of species there is an element of chance, as well as practical issues like dispersal abilities. By 5,000 years ago the temperate forest, as we know it today in eastern North America, had settled into place. Climate has largely remained stable and changes to distribution and structure of the forest has been largely a result of human activities – burning, wildlife management, clearing, species extinctions, and introduced species. The temperate deciduous forest is, of course, more than just a stand of trees. Though its story is described here largely on the basis of its tree genera and the age and patterns of arrangement of the trees, the forest is a living, breathing phenomenon. Other taxa, including shrubs, herbs, and grasses also have their place in the story. Fauna evolves in lock-step with flora and we can be certain that a dynamic story played out as the trees prospered, evolved, and in some cases went extinct. Acorns to ants, spiders to sunfish, everything was involved in this ecological drama.
Delcourt and Delcourt (1987). Columns may not add to 100% due to rounding.
Genus
18Ky BP
12-10Ky BP
6-4Ky BP
Abies
10
10
0
Picea
30
10
0
Pinus
60
40
30
Quercus
10
20
50
Carya
0
10
10
Acer
0
10
10
Juglans
0
0
<10
Nyssa
0
0
10
The story of the eastern forest then, is not only one of geographic and temporal reach of trees, but it is also one of pieces, processes, and phenomena. Here we find some of Earth’s greatest natural wonders: warbler migration, magicicadas and katydids, ephemeral spring wildflowers, and the brilliance of fall foliage. We find global centers of diversity for freshwater crayfish, freshwater mussels, and salamanders. We find, in a couple hundred acres of disturbed woods, the same tree species diversity that is met in western North America on over a couple million acres of our grandest national parks.
33
Forest References Graham, A. 2011. A Natural History of the New World: The Ecology and Evolution of Plants in the Americas. University of Chicago Press.
Grimmson, F. 2007. Middle Miocene floras of Iceland: the early colonization of an island? Review of Palaeobotany and Palynology 144(3-4): 181-219.
Delcourt, H. 2002. Forests in Peril: Tracking Deciduous Trees from Ice-Age Refuges into the Greenhouse World. McDonald and Woodward Publishing Company. Edwards, F. et al. 2017. Convergence, consilience, and the evolution of temperate deciduous forests. American Naturalist. 190: 88-104. Axelrod, D. I. 1966. Origin of deciduous and evergreen habits in temperate forests. Evolution 20:1â&#x20AC;&#x201C;15. Wolf, J.A. 1987. Late Cretaceous-Cenozoic history of deciduousness and the terminal Cretaceous event. Paleobiology 13:215â&#x20AC;&#x201C;226. Lohmann, G., et al. 2015. Effect of vegetation on the Late Miocene ocean circulation. Journal of Marine Science Engineering 3(4): 13111333. Salzman, U. et al., 2008. A new global biome reconstruction and data-model comparison for the Middle Pliocene. Global Ecology and Biogeography. 17(3): 432-447.
Flowering dogwood Cornus florida
Cawley, J. et al. 2001. An examination of the first sediment cores from Mountain Lake, Giles County, Virginia for diatoms and pollen. Virginia Journal of Science 52(4): 241-258. Levy, G. 1991. The vegetation of the Great Dismal Swamp: review and an overview. Virginia Journal of Science 42(4): 411-418.
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T HE P RESETTLEMENT L ANDSCAPE The subject of North America’s “presettlement landscape” has long been a topic of research, speculation, and debate. Among ecologists, historians, and others there exists a desire to understand the composition and structure of the vegetation at the time of European settlement. Such information can inform about the land’s ecological function and the ecological role of indigenous people. But understanding the presettlement landscape can also inform restoration efforts including the composition of native flora (and fauna), natural communities, and ecological processes. The central questions regarding the presettlement landscape include: what was the composition and structure of the northern Virginia Piedmont? Was it all forest? Were there
open areas? What was the disturbance regime? And what can be said about composition and populations of the fauna? Information regarding the landscape at Virginia’s founding 400 years ago comes from a variety of sources. Explorer’s journals and logs provide first hand qualitative descriptions, while surveyor’s witness tree records represent a random (somewhat) survey of trees from a given property. Paleoecological studies that typically use fossilized pollen to reconstruct historic or prehistoric landscapes can provide information on changes from presettlement to postsettlement times. I have not found palynological studies from the northern Virginia Piedmont. A study from the southern
35
Shenandoah Valley (Craig 1969) notes oak and pine dominance, however, the study’s focus is on older Holocene ecology. (Rokeby Farm contains a small perennial swamp wetland in relatively undisturbed woodland that could offer interesting palynological information.) Existing vegetation also provides a window into the past. Tree rings can reveal ages of trees as well as a proxy for growing conditions and stand dynamics. The rings of tree branches can shed additional light on growing conditions of trees and the environment immediately surrounding them. Long-lived herbaceous vegetation can indicate areas that have escaped the plow or that have been grazed. While an open field reveals only small fragments to me, pasture expert or soil scientist may in fact be able to interpret much history from a weedy meadow.
Tree Time The period of American Indian dominance lasted from 13,000 years ago to approximately 400 years ago. Native groups managed the land through agriculture, hunting, and burning, the latter of which had lasting effects on today’s landscape with the dominance of oak and hickory. We are finding today that, without burning, our oak and hickory forests shift to maple, beech, and other mesic species. European dominance began roughly 300 years ago. EuroAmericans, in much shorter time, have had far greater effects. Forests have been extensively cleared, plowed, and the soil eroded. Exotic species have been introduced, forever altering
the original flora and ecological processes. Animals of all sizes and habitats have been extirpated. Oak Spring contains all of these stories, clearly written down in its ancient oaks, stone walls, and in Goose Creek. While in the previous section we were dealing with Deep Time – reaching back tens of millions of years to uncover the evolutionary history of Oak Spring’s flora, in this section we are working on Tree Time: the span of time that includes the maximum ages for extant local trees. Oak Spring contains several trees that have witnessed the remarkable ecological and cultural transformation occurring since European settlement. This section describes what the land likely looked like when Oak Spring’s multi-century trees were saplings.
Written Sources There has been surprisingly little synthesized or researched information regarding the presettlement landscape and forest of Virginia. Considering Virginia was the birthplace of the nation and contains a disproportionate number of historic sites, battlefields, early settlements, and rich American Indian history, etc., it is surprising that the subject has not received greater study. It is nonetheless possible to refer to early explorer accounts that describe the landscape. For the Piedmont, many of these early descriptions note the mix of forest and savanna vegetation types. EARLY HISTORICAL ACCOUNTS John Lederer, a German physician and adventurer, was the first European to reach the Blue Ridge. In the summer of 1670
36
he followed the Rappahannock valley to its headwater springs on the Blue Ridge, probably near Manassas Gap. As translated by Talbot (1672), Lederer wrote of the openness of Piedmont country east of the Blue Ridge: We travelled thorow the Savanae amongst vast herds of Red and Fallow Deer, which stood gazing at us; and a little after, we came to the Promontories or Spurs of the Apalataeanmountains. These Savanae are low grounds at the foot of the Apalataeans, which all the Winter, Spring, and part of the Summer, lie under snow or water, when the snow is dissolved, which falls down from the Mountains commonly about the beginning of June; and then their verdure is wonderful pleasant to the eye, especially of such as having travelled through the shade of the vast Forest, come out of a melancholy darkness of a sudden, into a clear and open skie.
Writing more broadly of the Piedmont, Lederer notes: The Highlands (or Ahkontshuch) though under the same Parallels, are happie notwithstanding in a more temperate and healthful Air. The ground is over-grown with underwood in many places, and so perplext and interwoven with Vines, that who travels here, must sometimes cut through his way. These Thickets harbour all sorts of beasts of prey, as Wolves, Panthers, Leopards, Lions, […] and small Vermine, as wilde Cats, Foxes, Racoons. […] The parts inhabited here are pleasant and fruitful, because cleared of Wood, and laid open to the Sun. The Valleys feed numerous herds of Deer and Elks larger then Oxen: these Valleys they call Savanae, being Marish grounds at the foot of the Apalataei, and yearly laid under water in the beginning of Summer by flouds of melted Snow falling down from the Mountains. (Talbot 1672).
In this passage Lederer notes the contrast in vegetation from the wilder wooded areas to the more open inhabited areas
managed by American Indians, and the savanna landscape of the valleys and Piedmont in general. Also describing the Piedmont, Robert Beverly (1705) writes: The Heads of the Rivers afford a Mixture of Hills, Vallies and Plains, some richer than other, whereof the Fruits and Timber-Trees are also various. In some Places lie great Plats of low and very rich Ground, well Timber'd; in others, large Spots of Meadows and Savanna's, wherein are Hundreds of Acres without any Tree at all; but yield Reeds and Grass of incredible Height…
In an excellent review of landscape burning by American Indians in Virginia, Brown (2000) notes the many references to burning and the open savanna landscape from historical documents. He writes: “European explorers reported evidence of widespread grassland or savanna in two parts of Virginia—the Piedmont and the Shenandoah Valley.” The Shenandoah Valley lies west, just over the Blue Ridge from Oak Spring, and is the driest region on the state. In the Piedmont, the convergence of slightly drier conditions, created by the rain shadow of the Blue Ridge, and the burning by indigenous people for the purposes of agricultural clearing, hunting, and range management (Brown 2000) created prime conditions for a mixed forest and savanna landscape. Brown concludes: “In the Piedmont, dry oak– hickory forest in the rain shadow of the Blue Ridge likely opened into patches of savanna or grassland covering hundreds of acres.”
37
SOURCES
OF
EVIDENCE
FOR INDIAN
FIRE USE
at any given time, on hundreds of acres of widely scattered tracts at various successional stages. Where populations were relatively concentrated, this broad pattern of impact probably helped provoke warfare among peoples competing for limited resources such as hunting grounds. As stocks of deer declined on the coastal plain, for example, the Powhatans organized large upriver hunts in areas claimed by the Monacans, leading to occasional bloody battles (Rountree 1989; Strachey 1612).
Did wildland burning by American Indians affect presettlement ecosystems in Virginia? Relevant sources of evidence (adapted from Whitney 1994) might include: • Historical materials, including written accounts, maps, and draw-
ings; (Many descriptions ofsurveys; early Virginia landscapes occur in the • Statistical records, especially land • Studies of old-growth forests or ancient individual trees; historical A complete • Archeologicalrecord. evidence, especially from excavated review Indian villageof those, while tempting, sites; and is• beyond the scope of this document. Paleoecological studies, including pollen and charcoal analyses fromSee the references sediments. below for additional sources and especially Brown (2000) and Evidence from different sources does not always agree. Despite eyewitness accountswithin.) of bison in Virginia, archeologists have found no supsources Hunting. Fire was widely used in porting evidence such as bison bone fragments in excavated Indian fire- and trashpits (Stapleton 1999). But bison did not spread into Virginia until the 14th or 15th century (Haines 1970), whereas most archeological excavations are on earlier, “prebison” sites (Brinker 1999).
Virginia during organized hunts. Villagers, “commonly two or three hundred together” (Strachey 1612), would form a large circle and ignite the forest leaf litter, Blue Ridge Mountains
C
A
P
I P
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Major Indian trails Areas of inhabitation on the Coastal Plain Areas of reported prairie/savanna Possible bison migration corridor Figure 1—Virginia in about 1600, showing some of the areas where fire use by American Indians might have affected presettlement vegetation. Areas of Indian settlement on the Coastal Plain are based on Smith (1612); areas of settlement in the interior are not shown, but were similarly concentrated along waterways. American Indians burned lands adjacent to their villages for agriculture, hunting, and other purposes, opening the forest and promoting pines and oaks over less fire-resistant species such as maples and beech. The western Piedmont and Shenandoah Valley had fire-maintained grassland or open woodland that probably reached southwestward along valleys to the Cumberland Gap, providing a migration corridor for bison (Haines 1970). The major Indian trails shown were used for regional trade and travel (Lambert 1989; Randolph 1973); not shown are the many local trails along rivers and ridges. Frequent fire use to maintain such trails probably formed corridors of open pine and oak forest. Illustration: Gene Hansen Creative Services, Inc., 2000.
I landscape ca. 1600.
Volume 60 • No. 3 • Summer LLUSTRATION AND2000 CAPTION
I could find only one regional study to have used witness tree data to examine the presettlement vegetation in the northern Virginia region. Orwig and Abrams (1994) examined forest and land use history at Fredericksburg and Spotsylvania National Military Park, approximately 50-miles southeast of Oak Spring. Regarding land survey records of witness tree data Orwig and Abrams (1994) write:
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property. Often described as “the large white oak” or “a sycamore sapling” the bounds may have been impermanent but the record of tree species data is incredibly useful today. Many studies in New England and other eastern states use witness tree data to uncover the presettlement vegetation.
FROM BROWN
(2000) showing Virginia 31
WITNESS TREE RECORDS The metes and bounds descriptions of early land surveys typically used trees to denote a bound, or corner, of said
Presettlement forests were dominated by white oak and red oak, while black oak and hickory species obtained only minor importance. It is important to note that white oak was a favored witness tree species by early surveyors and therefore may be somewhat overrepresented in the survey. During the early postsettlement years, white and red oaks still dominated among witness trees, although white oak declined from its initial level. In contrast, hickory, pine, and post oak experienced slight to moderate increases during this time.
The Fauquier County Land Records Office contains a trove of information on region’s settlement-era landscape. With deed books dating to 1759, records likely contain thousands of tree data points recorded during settlement times. While researching Oak Spring’s deed transfer history, I took a cursory examination at some of the earliest metes and bounds descriptions, and while I was unable to pinpoint the location of a chosen survey, a pattern emerged of relative tree species
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importance. The following table lists tree species in relative abundance prior to 1800 based on a quick read of deeds:
of presettlement or settlement era trees, here meaning those trees that are 200 years old or older:
SPECIES LISTED IN EARLY FAUQUIER COUNTY DEEDS Frequently mentioned Infrequently mentioned White oak (Quercus alba) Sycamore (Platanus occidentalis) Red oak (Q. rubra) Chestnut (Castanea dentata) Hickory (Carya spp.) Maple (Acer spp.) Spanish oak (Q. falcata) Beech (Fagus grandifolia) Walnut (Juglans spp.) Crabapple (Malus sp.) Black oak (Q. velutina) Plum (Prunus sp.) Dogwood (Cornus florida) Ash (Fraxinus sp.) Box oak (Q. stellata) Sassafras (Sassafras albidum)
TREES AT OSGF OLDER THAN 200 YEARS. Additional details occur in the vegetation inventory section. Tree Approximate age Location at OS Black gum 390 yrs (ca. 1630) South of cemetery White oaks 280 yrs (ca. 1735) West of cemetery White oak 260 yrs (ca. 1755) At Springhouse Pond White oaks 280 yrs (ca. 1735) Steep forest by Goose Cr. Post Oak 320 yrs (ca. 1697) Steep forest by Goose Cr. Black gums 200+ Forest slope, cemetery, etc. Other Oaks 200+ Forest slope
These cursory results correspond with Orwig and Abrams (1994) conclusions of oak dominance (especially white oak) and descriptions from early accounts (Brown 2000; Maxwell 1910; Rice 2009). Early 1800s deeds for Oak Spring list most of these species with white oak as most common, and more obscure trees listed along Goose Creek. Additional work could be done researching Fauquier Countyâ&#x20AC;&#x2122;s deed record to reconstruct regional vegetation history.
Field Evidence This document is arranged such that the first section provides background context, and the second section contains the field inventory. Here, however, I describe field conditions at Oak Spring as they shed light on the propertyâ&#x20AC;&#x2122;s presettlement landscape. This information is expanded in the vegetation inventory section (trees) later. Oak Spring contains a number
The black gum over 300 years is noteworthy, however, the species is the longest living broadleaf tree in eastern North America (Abrams 2007) with the oldest known tree at 700 years in New Hampshire. Trees 500 years old are common. The tree at Oak Spring was hollow and I have interpolated its age based on visible rings. Blackgum made up a very small portion of the presettlement landscape, typically 1 percent according to witness tree data (Abrams 2007). Additional ancient black gums occur locally (off OSGF property) perhaps reaching 500 years, or more. Blackgum has high shade tolerance, high resistance to fire in mature trees, low preference as deer browse, exceptionally slow growth rate, and its wood is prone to rot and is of little value to people. For these reasons trees have persisted. Black gum follows disturbance: so for this tree the 1600s must have
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included fire, hurricane, or small-scale wind event. This is the earliest ecological history we have for Oak Spring.
find any census of mussels in Goose Creek (the Goose Creek Association could not provide information).
As occurs elsewhere in the east, white oaks at Oak Spring have attained old age. Trees confirmed to 280 years appear to be mostly forest-grown trees as they are tall and lack the low spreading limbs of open grown trees. However, the oak at the Springhouse Pond, aged to 260 years does contain original-growth low branches (not epicormic branches that released later) indicating the tree has been open grown since germination. Cores from a high branch show the tree has been open-grown since before 1800 suggesting at least a partially open landscape in the middle 1700s. Other trees at Oak Spring indicate closed forest at that time. It’s possible the tree was released by burning as settlement got started. American Indians were largely gone at this time, agreeing in 1722 in the Treaty of Albany to remain west of the Blue Ridge.
Along the floodplain and riparian area, perhaps the greatest absence today is river cane (Arundinaria gigantea) and/or switch cane (Arundinaria tecta). These bamboo species (with a third species in the Appalachian Mountains) comprise the only bamboo species in North America. They typically form dense “canebreaks” along rivers. Native Americans used them for arrows and baskets among other material goods. Europeans used them as livestock forage as horses, cows, and hogs all eat them (Lott 2012). For this reason, despite numerous historical accounts of vast areas covered in cane, the plant is rare in Virginia and much of the southeast (Lott 2012). It occurs in only a few northern Virginia counties. It should be a focal species for restoration efforts along Goose Creek.
Presettlement Synthesis Goose Creek In Presettlement times Goose Creek may have looked much like it does today in some forested sections. But the composition and function of the stream would have been different. Indigenous people appear to have had a limited presence in these central uplands away from large rivers. The stream would have had a robust mussel and fish population of an unknown number of species. As a taxonomic group, freshwater mussels achieve greater diversity in eastern North America than anywhere else globally (70-80 spp. in Virginia). They are especially sensitive to water contamination and many or even most species are extirpated or extinct. I was unable to
Based on these disparate and incomplete sources, it appears the landscape of Oak Spring, and the Piedmont in general, fits the commonly held theory of a presettlement oak–hickory landscape with patches of forest, woodland, and savanna. The contemporary landscape is a reflection of this history, and the cultural land use changes that accompanied European colonization. At Oak Spring, this oak - hickory mosaic contained much white oak, red oak, bitternut hickory, pignut hickory, shagbark hickory, mockernut hickory, and some amount of post oak, dogwood, tulip poplar, and black gum, among many others in the uplands. Herbaceous woodland flora included spring beauty, trillium, Dicentra sp., bloodroot,
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and others. The Goose Creek riparian area contained sycamore, among other hardwoods, and likely a cover of river cane, among other plants.
Presettlement Forest References
The presettlement landscape was a reflection of the cultural practices of the period and the generations preceding it. In this case oak-hickory communities, especially woodland and savanna types, are considered a disturbance climax; that is, it is a steady state community type that is dependent on periodic fire disturbance. Abrams and Nowacki (2008) suggest the dominance of oak and hickory in the presettlement landscape, and by extension the present-day landscape, is a legacy of American Indian burning for the purposes of fruit and mast trees. What we view today as a natural landscape (oak–hickory) is, in reality, a cultural one.
Abrams, M. and G. Nowacki. 2008. Native Americans as active and passive promoters of mast and fruit trees in the eastern USA. The Holocene 18(7): 1123-1137.
Lacking periodic disturbance, like American Indian burning, species composition (and function) shifts to more mesic species including maple and beech. Because Oak Spring has an unsustainably high deer population, we don’t see this forest shift occurring because tree regeneration largely does not occur. By examining witness tree records from Upperville area deeds and Fauquier County more broadly, we could develop a clearer picture of the presettlement landscape. Such an undertaking would contribute to the gap that exists around Virginia’s presettlement landscape.
Abrams, M. Tales from the blackgum, a consummate subordinate tree. Bioscience, 57(4): 347-359.
Beverley, R. 1705. The history and present state of Virginia, in four parts. London. http://docsouth.unc.edu/southlit/beverley/beverley.html Brown, H. 2000. Wildland burning by American Indians in Virginia. Fire Management Today, 60 (3): 29-29. www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsbdev3_000385.pdf Lott, G. 2012. River cane and Virginia Native Americans. Points: Newsletter of the Virginia Archeological Society. 33 (4): 1-4. http://www.mcasv.org/Points/APR_2012.pdf Maxwell, H. 1910. The use and abuse of forests by the Virginia Indians. William and Mary College Quarterly, 19 (2): 73-103. https://www.jstor.org/stable/pdf/1921261.pdf Orwig, D. and M. Abrams. 1994. Land-use history (1720-1992), composition, and dynamics of oak-pine forests within the Piedmont and Coastal Plain of Northern Virginia. Canadian Journal of Forest Research 24: 1216-1225. Talbot, W. 1672. The discoveries of John Lederer, in three feveral marches from Virginia to the weft of Carolina and other parts of the continent. Holborn. http://rla.unc.edu/Archives/accounts/Lederer/LedererText.html
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H UMAN H ISTORY : I NDIGENOUS TO THE M ELLON E RA The human history of Oak Spring, Upperville, and the northern Piedmont more broadly, is a story of humans working with and against nature. Indigenous people, their ways of living, stories, and their conflicts, were all linked to natural world around them. The Europeans, from the first explorations all the way up to Fauquier’s Hunt and Horse Country has everything to do with geography and soils. It also has to do with Oliver Cromwell and events in Europe. Today one could not call the northern Piedmont a wilderness. But if wilderness is a place where nature – humans included – lives among complexity and uncertainty, then this region has never not been a wilderness. To bring us to the Mellon’s Oak Spring, and everything that accompanies it, we take a broad view of the events – obvious and obscure – that have shaped this area. From indigenous people to Lord Fairfax, the Civil War, and Hunt Country, the region’s rivers and ridges have a unfolded a remarkable story.
American Indians: 17,000 BP to 1722 It’s not possible to thoroughly review the deep history of indigenous Americans in this region. From their origins, presumably via northwest North America, down to the specific tribes and languages they spoke just a few generations ago, the facts are mostly reliant on still emerging research. What is clear from the previous section about the presettlement landscape is that they had an enormous role in shaping
Virginia’s landscape – the legacy of which is still with us. This summary will focus on American Indian history in Virginia’s Piedmont. Indigenous people in the Americas can generally be traced through DNA back to arrival from Asia via Alaska. Whether they travelled by boats or through an ice-free corridor is subject to much debate. What is clear, however, is that by 13,000 years ago, people had populated the Americas. Their large Clovis style hunting points are widely found. But Virginia is home to two sites (of a few dozen) in the Americas that suggest older human occupations. On a dune of windblown sand near the Virginia coast, Cactus Hill revealed lithics, animal bones, and charcoal remains. Soil samples date occupation of the site to 17,000 to 15,000 years BP. Similarities of Cactus Hill lithics to those from Spain and France suggested a Solutrean hypothesis – a westward arrival from Europe to North America before 15,000 years BP. The idea has been broadly rejected. A second Virginia site at Saltville, in the state’s southwest corner, also indicates pre-Clovis inhabitation. There, a geological anomaly created a shallow lake where animals congregated in pursuit of minerals. Ideal fossil-forming conditions preserved mammoths, mastodons, horses, musk oxen, and short-faced bear. Human activity is evidenced though butcher marks on megafauna bones, stone tools, a grease deposit believed to be from cooking, and a midden of giant floater mussel shells. Together these artifacts indicate
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sporadic occupation from 17,000 years to 14,500 years BP. People and megafauna overlapped before the animals’ extinction around 11,000 years ago.
(warm period). Terrestrial species increased in importance over aquatic species. At 1,000 years ago, many more native people lived along the coastal plain than in the interior (Rice 2009). The Fall Line prevented anadromous fish from ascending higher into the country.
During Paleo-Indian times (17,000 to 10,000 BP), habitation would have included small hunting camps in locations offering a variety of animal habitat types, especially near water. By Late Woodland times indigenous lives included aspects we Landscape diversity was critical. As climate warmed during the commonly associate with American Indians: corn was farmed, Holocene Climatic Optimum, vegetation shifted to deciduous large burial mounds were constructed on floodplains of major forest and mast trees, and as streams, and villages were built. It was not difficult to find a place with good megafauna were killed off, people Yet, even by the 1200s, Potomac adapted. During Archaic times region peoples “remained fishing, or level riverfront soils, or freshwater (10,000 to 3,000 BP) upland sites societies with agriculture rather marshes, or mixed deciduous forests, but few had robust use as people seasonally than agricultural societies” (Rice places had all of these necessities of life. migrated from rivers, to uplands, 2009 p.29). Where all of these features came together, one and back. People used aquatic resources such as anadromous fish People built stockade villages, could find a settlement. (Rice 2014 p.62.) and mussels, and switched to primarily along larger rivers. Rice upland mast from oaks and (2009) suggests this architecture chestnuts in the fall. (Oak Spring has dozens of artifacts from was a result of chronic warfare attributed to stresses from the this time period; see Archeology in Part 2.) onset of the Little Ice Age (beginning roughly at year 1400). As robust agriculture developed during the preceding The Woodland period (3,000 BP to 1,600 CE) brought to the centuries, populations grew. As climate became less region ceramic pottery and the bow and arrow. Trade goods conducive to agriculture, stresses emerged. People moved moved materials from north of the Potomac and the down latitude and downslope to warmer, more fertile areas. Shenandoah Valley to Piedmont Virginia and beyond. In Piedmont oak-hickory forests offered the best locations for Middle Woodland times (500 BCE to 900 CE) native people game but “by the end of the 16th century, the interior above adopted agriculture, and the primary habitation sites became the Fall Line was almost completely uninhabited” (Rice 2009 backwater wetlands on floodplains with rich soils. Agriculture p. 47). Egloff and Woodward (2006), however, note that began in earnest around 900 CE during the climatic optimum Capitan Smith in 1608, and other explorers later, observed
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many villages just above the falls on many rivers. Nonetheless, habitation was concentrated along larger rivers and river confluences. Canoes served as primary transport. It is impossible to trace the tribal/language groups that inhabited Virginia’s Piedmont over the past 10,000 years. However, Sioux groups inhabited the Piedmont region in historic times. They migrated from the Ohio Valley region a few thousand years prior (Nash 2017). The Monacan and Manahoac, tribes associated with the Piedmont, were branches of the Sioux (Egloff and Woodward 2006). Their territories reached eastward to the Fall Line. Their name meant, “they are very merry” in Algonquin. By the late 1600s,
Iroquois had pushed them south and west and took a large influence and presence in the Piedmont. It was Iroquois who became involved in later treaty negotiations regarding the Blue Ridge and Piedmont (Grymes 2017). In historic times we see decline brought to Native Americans from Europeans. Explorer John Lederer in 1669 noted abandoned villages and overgrown sites. In 1713, Virginia Governor Spotswood forcibly removed natives resulting in decimated communities. As discussed in the presettlement forest section earlier, American Indians actively shaped the land through farming, fishing, hunting, and burning the woods. While the American Indians themselves were swept away by European diseases, “Indian ways were swept away by the expansion of European capitalism” (Rice 2014 p.6). As European settlement progressed in the 18th century, early efforts emerged to push natives west. For the sparsely inhabited Piedmont region, a series of three treaties pushed natives east to west, over the course of 50 years. First, in response to Indian raids on the Virginia borderlands, the 1684 Treaty of Albany blocked English settlement in the Iroquoiscontrolled Piedmont at the base of the Blue Ridge. The area was to be used for native hunting and travel (Grymes 2017). The English were focused on Fall Line areas at the time.
MAP OF AMERICAN INDIAN GROUPS IN VIRGINIA at the time of contact. Source Virginia DHR.
The second, and most noteworthy treaty was the Treaty of Albany in 1722. This treaty, signed by governors of several
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colonies and representatives of indigenous groups, among other actions said that the Iroquois would remain north of the Potomac River, and west of the Blue Ridge. The treaty as written: We agree to this Article & faithfully promise not to pass over the great River Kahongoronton which the English call Potowmack nor the great Rid[g]e of Mountains which extend along your Frontiers. (Grymes 2017) The Blue Ridge was the demarcation between the Virginia Colony and the Five Nations to the west. Settlers nevertheless continued moving west, past the Blue Ridge. Indians objected and Virginians argued 20 years later that the 1722 treaty was to keep Iroquois from trespassing east, and other Virginia-allied tribes from going west, but did not bar settlers from pushing west. This was resolved in the 1744 Treaty of Lancaster in which the Iroquois ceded all rights to lands in Virginia west of the Blue Ridge (Grymes 2017). That Thomas 6th Lord Fairfax was promoting settlement in his vast 5-million acre holding contributed to the discontent.
Lord Fairfax and Settlement: 1660 to 1860 As Native Americans encountered Europeans in Virginia during the 17th century, events taking place in England and Europe would unfold in ways that made Virginia’s Piedmont and also Oak Spring what they are today.
England in the 1640s was engaged in a civil war. Led on one side by Oliver Cromwell, the war pitted parliamentarians against royalists – supporters of Charles I. In the end, Charles I was executed, and his son, Charles II, was exiled to France. In 1649, when Charles II was in exile, he granted Virginia’s Northern Neck to a group of seven loyalist supporters aiding him in regaining the throne. The grant was made active in 1660 when King Charles II was restored. The land had never been explored nor mapped and was simply described as: “a porcon [sic] of Virginia ... bounded by and within the heads of the Rivers Rappahannock and Patawomecke....” The 5.3 million acres between the Potomac and Rappahannock Rivers was unexplored. Over time, through buyouts and inheritance, most of the proprietary devolved to Thomas Culpeper, 2nd Baron Culpeper. Culpeper was a loyalist of Charles I, and he left England after Charles was executed. Charles II made him Governor of Virginia. He went there in 1679 but left a few years later during an uprising in the colony. When Culpeper died in 1689 his estate was left to his daughter Catherine Culpeper. Catherine Culpeper married Thomas 5th Lord Fairfax in 1690. Lord Fairfax died in 1710 and Catherine died in 1719. Their son, Thomas, 6th Lord Fairfax, inherited five-sixths of the Proprietary. He inherited the final share from his grandmother.
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Fairfax hired Robert Carter in 1722 to administer the land. Carter became wealthy doling out Fairfax land and retained much land for himself and heirs (300,000 acres). So much so that when Carter died, Fairfax decided he had to take control himself. (Carter, whether Robert or his heirs, is a common grantor on many early property transfers including around Oak Spring.)
THE FAIRFAX PROPRIETARY includes 5.3 million acres granted by King Charles II to a handful of loyalists. Oak Spring shown with red star. Image: Grymes 2017/Virginiaplaces.org
Nearly 70-years after Charles II granted it, the Propriety was finally owned by one person: Thomas 6th Lord Fairfax. He owned all 5.3 million acres of the Northern Neck Proprietary. But it took him another 25 years to gain clear title. The Virginia Commonwealth disputed the boundaries of the proprietary and made efforts to extinguish Fairfaxâ&#x20AC;&#x2122;s claim. The colony also offered to buy the property. The Fairfax family had King William and Queen Mary reaffirm the grant to keep it active. Fairfax had to conduct surveys to determine where the headwater springs were located and which branches of which rivers were the main stems.
Thomas 6th Lord Fairfax arrived in 1735 on his first trip to America. After returning to England to settle legal issues, he returned to America in 1747 to continue his Proprietary. He hired a young (16 years) George Washington in 1748 to survey lands west of the Blue Ridge, and they remained friends. In 1751 Fairfax moved west to the Shenandoah Valley. Despite being sparsely settled, he felt lands east of the Blue Ridge were too civilized and the foxes too few, so he built Greenway Court Manor â&#x20AC;&#x201C; a humble farm on the Virginia frontier in the Shenandoah Valley. The region still held much game. He hired his nephew, Thomas Bryan Martin, from England, to be the steward and land agent in 1751. Fairfax rarely sold land; it was leased on terms of 21 years or three lives (man, woman, child, or other combination). Lessees were required to build a house at least 16 by 20 feet with a masonry chimney, and plant 100 fruit trees, which were to be kept under fence. They also had to pay quitrents in money or other commodity. Most lessees were absentee; they sublet lands or developed them with indentured servants and tenant farmers. Fairfax found lease payments difficult to collect.
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Fairfax carved out a number of parcels for himself. These were prime lands, called manors, upon which he intended to build personal estates or enjoy his favorite pastime: fox hunting. Most notable of these was the Manor of Leeds. The manor was named for Leeds Castle, England, the Fairfax family seat. Like other manors, Leeds was choice land that Fairfax was keeping for himself. Once surveyed it tallied 122,000 acres centered on the Blue Ridge between Ashby Gap and Manassas Gap. On the 1736 map by John Warner, Oak Spring lies in the middle of The Manor of Leeds, however, once it was surveyed, what is now Oak Spring fell outside its bounds by 6 miles. (Today a “John Marshall’s Leeds Manor Historic District” lies southwest of Oak Spring along Leeds Manor Road.) Other important manors included Gooney Run Manor, South Branch Manor, and Greenway Court Manor. Upon his death in 1781 at age 88, his will passed ownership of his manors not to his close nephew Thomas Bryan Martin, but to his nephew in England, Denny Martin (brother of Thomas) on the condition that he change his name to Fairfax. He did, but a Virginia law in 1779 outlawed land ownership by British subjects so ownership of the Northern Neck was thrown to the courts. Denny Fairfax’s attorney was John Marshall, future Supreme Court chief justice. Thomas 6th Lord Fairfax’s other 5/6 shares went to his brother Robert 7th Lord Fairfax. This too, ended up in the courts.
Denny Fairfax was forced into a deal with the state of Virginia to sell the manor lands to John Marshall and brother James Marshall. The remaining lands would be confiscated by the state. Any existing citizens that had acquired grants were allowed to keep their lands. Denny Fairfax died in 1800 and The Northern Neck Proprietary was dissolved by 1806. In the midst of the Fairfax dealings, the county of Fauquier was founded in 1759. Formed from Prince William County, and named for Francis Fauquier – governor of Virginia, the Tidewater region elite resisted the formation of Fauquier as it would dilute their power. Nonetheless, the county was formed after 5 years of petition at Williamsburg. First settlers entered the upper Fauquier region in the 1740s, 1750s, and 1760s. They looked for places with springs where black locust and walnut (Juglans or Carya) grew together (Scheel 2017) indicating rich soil. Soils on the east side of the Blue Ridge were known to be quite fertile and springs tended to rise on east-facing slopes (as Oak Spring’s do). Lying on the primary road from Washington DC to the Shenandoah Valley via Ashby Gap the region had great appeal, strategic and economic value. The importance of this travel corridor during all historic periods cannot be overstated. The oldest structure known from the neighborhood around Oak Spring occurs on what is today Slater Run Vineyards. There, John Glascock built a house on Goose Creek in 1720.
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Upperville was formed from a 1,400-acre land grant to Rev. Charles Green in 1742. The land was divided with Josephus Carr buying 180 acres upon which Carrstown was built on Panther Skin Run. Carr built a residence and general store in 1780 at the western end of town by an existing McPherson family mill. (The mill was later destroyed by Union forces.) Carr laid out the town in 1797 such that all properties fronted what is now Rt. 50. McPherson built what is today the Hunter’s Head Tavern in Upperville, around 1750. Carr purchased McPherson’s farm and lived in what is now the tavern. In 1818 the name Carrstown was replaced by Upperville. It’s unclear as to exactly why the name Upperville was adopted, however, there is reference to the “upper” and “lower” parts of town. Eugene Scheel (2017) suggested that the town was in the “Upper” most (northern) portion of Fauquier County. According to the National Park Service, “The town has seen no significant expansion since the War between the states” (NPS 1972). Of Upperville’s 75 buildings, ~50 are 19th century and half of those predate 1860. Closer to Oak Spring we find additional settlement from the 18th century. At Blue Ridge Farm (Grayson), across the road from Oak Spring, is the Fountain Hill House. Fountain Hill was part of a 9,699-acre tract granted in 1731 to Landon Carter (also listed as 5,487 acres in an early deed). His father, Robert “King” Carter, administrated Lord Fairfax’s Proprietary in the early 1700s and enriched himself with 300,000 acres of Fairfax’s land. Lands passed from Robert to Landon upon the
elder’s death in 1732. Landon Carter died in 1778 and the land went to his sons, John and Landon II. In 1794 John’s son, also named John, leased land to Joshua Fletcher. Fletcher built a stone house (as required from his lease) and that Fountain Hill House still stands today. Joshua Fletcher was father of Oak Spring settler Robert Fletcher. He built a log cabin around 1830 at the site of the Mellon residence. (As the 9,699/5,487-acre tract included land on the north side of Goose Creek, we presume this also included Oak Spring, which for all practical purposes is adjacent property to Fountain Hill. See the deed search section in Part 2.) Carving a new farm out of raw land is messy business: clearing and burning with little access to supplies. Stones were cleared, fields created, and fences built. Slaves did much of this work. In 1782 one-third of Fauquier people were slaves. Though they were settled late on account of being away from large rivers, Fauquier and Loudoun Counties had the highest crop yields in the state on account of rich basaltic soils. Settlers of upper Fauquier did not start off wealthy – many were Scottish, Irish, or German immigrants, and also Quakers from the north (Loudoun County was strongly Quaker and also disapproving of slavery). But on account of good soil, they became wealthy over time and added acreage to their holdings. By the mid-1800s, they had functioning farms with big houses, stock and outbuildings, and they settled in to the seasonal rhythm of farming. Their markets were local, and also in the low country.
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Civil War to Hunt Country: 1860 to 1930 As Fauquier farms prospered, discontent was brewing in the young nation. With the fertile Shenandoah Valley just over Ashby Gap to the west, the nation’s capital Washington DC to the east, and Richmond to the south, Fauquier was in the crosshairs of the Civil War. This triangle was so intensely fought over that control of nearby cities Winchester and Warrenton during the War changed hands between Union and Confederate forces more times than any other cities in the country. Shenandoah Valley was “the breadbasket of the Confederacy” and incredibly strategic. Ashby Gap, and Fauquier’s other gaps were important holdings as Union and Confederate forces tried to control access through the mountains between Washington DC and Shenandoah. As a result of its geography, greater Upperville saw a number of skirmishes and small battles during the war. Union occupation of Upperville began March 15, 1862 and lasted on and off for three years. Fauquier Historical Society notes: For the citizens of Fauquier County, the shifting military presence and action provided a never-ending daily drama. Days, and sometimes nights, were filled with episodes ranging from inconvenient and annoying, to dangerous and terrifying. Previously quiet lives were suddenly disrupted by small skirmishes, wholesale destruction of communications and transportation links,
plundering of civilian property, and the constant unwelcome presence of soldiers indoors and out. (FHS 2008 p. 86)
Later, in November 1862, Ida Powell Dulany living across the road from what is now Oak Spring at a farm called Oakley, described the events of the day: The house had been crowded with poor hungry sick soldiers… Gen. Stuart’s cavalry fell back slowly before the enemy occupying the ground as he retreated. I sat on the balcony of my room and watched the battle, which became very distinct from flashes of artillery as the night came on. With the aid of a spyglass we could see many movements of our men, the enemy being entirely concealed by the woods. It is strange in our sheltered, quiet country, to hear the roar and see the flash of artillery, to watch the movements of an army and feed at night dozens of soldiers weary with a hard day’s fight.
The most prominent and well-regarded Civil War name – celebrity even – around upper Fauquier today is John S. Mosby. In 1863 captain Mosby collected a band of followers that would become known as Mosby’s Rangers. Mosby, 30years old at the time, commanded this small, nimble, partisan group with speed, surprise, and shock to oppose the Union occupation of Fauquier and Loudoun Counties. He was based loosely out of Rectortown, a few miles south of Oak Spring, and his group was supported and quartered by locals.
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Mosby earned the nickname “Grey Ghost” for his ability to strike unnoticed and disappear. His “guerilla tactics and willingness to live on the fly produced a level of success that baffled and enraged their Union targets” (FHS 2008 p.90). Some 2,000 men served under Mosby; 500 were captured and 100 died. Whatever one thinks of the Confederate allegiance, Mosby’s deft, resolve, and results were impressive and cannot be denied. General Lee described Mosby as: “zealous bold, and skillful, and with very small resources he has accomplished a great deal.” (Mosby nonetheless befriended President Grant (the former Union General) long after the war and they worked together to the distaste of retired Rebels.) In June of 1863 the Battle of Upperville would be the largest local engagement. After a battle near Middleburg days earlier, the Battle of Upperville began at the Ashby Gap Turnpike on the stone bridge over Goose Creek. (The bridge was built in 1802 and still stands.) The Union’s goal was to penetrate Gen. J.E.B. Stuart’s cavalry screen of Lee’s army heading to Gettysburg from the Shenandoah Valley. The Confederate goal was to prevent Union forces from reaching Ashby Gap and sighting the Northern Virginia Army. As Union forces reached the bridge from the east, they met resistance. They worked to ford Goose Creek, but heavy rain made this difficult. Once successful, they pushed the Rebel group back, west to Upperville, where more action took place. The groups moved about during the day before taking up defensive positions. Overall, 7,000 Union men were
Mosby’s Rangers were featured on the cover of Harper’s Weekly in September 1863.
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involved against 3,200 Rebels. The Battle of Upperville had an estimated 400 casualties combined. The last major Civil War activity in upper Fauquier was The Burning Raid in late November 1864. The destruction wrought during this 5-day event was unmatched during the battles and skirmishes during the rest of the War.
With the tip, and help from her slaves and servants, Dulany herded the plantationâ&#x20AC;&#x2122;s cattle into the woods. She noted that she awoke the next morning to see: "about thirty soldiers . . . to the haystacks and soon had them blazing. . . . Two Yankees stayed by the granary till the flames made such progress that it was impossible to save it." Days later she wrote:
In an effort to thwart Mosby, lower his stature among locals, and eliminate local support for the Rebels, General Ulysses S. Grant ordered Gen. Sheridan with 3,000 soldiers, to instruct his men: You will destroy and consume all forage and subsistence, burn all barns and mills with their contents, and drive off all stock in the region the boundaries of which are described above . . . no dwellings are to be burned and that no personal violence be offered to citizens. (Scheel 2004)
The Union soldiers crested Ashby Gap on November 28 to carry out The Burning Raid on northern Fauquier County and Loudoun County (essentially the Loudoun Valley). Three brigades were divided geographically and set fire to everything, save homes. Ida Dulany, at Oakley (neighbor to Oak Spring), described how on the evening of Nov. 28, Union officers tipped her off that her outbuildings and crops would be burned "to render [Oakley] utterly uninhabitable for Mosby's Guerrillas."
We could mark the progress of the Yankees, in every direction dense columns of smoke arising one after another, from every farm through which they passed. . . At night we could look out and see the whole country illuminated by immense fires.
The unfortunate irony of The Burning Raids was that many victims, especially in Loudoun County, were pacifist Quakers and Union supporters. Overall, Sheridan estimated Union forces had driven off 6,000 cattle, 5,000 sheep, and 700 horses, while 1,000 hogs were slaughtered. Destroyed infrastructure included at least 8 mills and 230 barns. At least 10,000 tons of hay and 25,000 bushels of grain were lost. Four months later, in April 1865, the War ended. War-weary residents of upper Fauquier County submitted claims to the federal government for lost property, which were paid in the 1870s. (Oak Springâ&#x20AC;&#x2122;s Pony Barn, built by Robert Fletcher in 1833, likely survived and was rebuilt in 1915.) It was a time to rebuild, refocus, and return to the aspects of living upper Fauquier was known for.
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Fauquier County in 1865 had 10,000 newly freed African Americans. Roughly 2,000 of them moved out of the county before the 1870 census. A handful of freed slaves founded the small settlement of Willisville, east of Upperville. The War left so much upheaval at so many levels – lots of dead young men, destroyed property, and most of all the end of slavery – that a period of adjustment was inevitable. By the 1890s and later the “war widows” of the Piedmont grew old and began selling farms in droves. Because upper Fauquier was distant from navigable rivers, large armies did not overwinter in the area and major battles were not fought there. Where armies overwintered in the low country, they destroyed houses and other infrastructure. Real estate advertisements marketed properties as “no war damage” or “very little war damage” to attract buyers. Wealthy industrialists from the north were attracted by the opportunity to buy large houses (a result of rich soils), and big properties in the burgeoning Piedmont Hunt Country. For example, “in 1903 one could buy 1,000 acres and a huge house for $65,000” (Scheel 2017). During the transition from agriculturalists to Hunt Country farmers, Fauquier and Loudoun maintained the highest yields in the state (Scheel 2017). Corn, wheat, and hay were the biggest commodities, while apple and peach trees totaled 180,000 trees in Fauquier County. (The 1937 aerial photograph of Oak Spring shows several orchards, including along Peach Tree Lane.) In 1910 Fauquier County was 5th in the state for sheep production.
Fox hunting had been practiced since colonial times by private packs of a landowner. Lord Fairfax bypassed the Piedmont for his estate because he felt the foxes were more abundant in the Shenandoah Valley. George Washington and Lord Fairfax fox hunted together many times. The Dulany family founded the oldest hunt, the Piedmont Hunt, in 1843. More clubs sprung up in Loudoun, Fauquier, and other counties in the mid-19th century. In 1898 the region was thrust into national importance for fox hunting when Harry Worchester Smith (Massachusetts) hunted Upperville at Oakley Farm (Dulany’s farm). An international Foxhound Match was then staged in Upperville in 1905. Within a couple years, there were dozens of clubs in the Loudoun-Fauquier-Clarke counties area. “This region, known as the Hunt Country and representing an area of about 1,000 square miles, was and still is, considered to be the finest foxhunting countryside in America” (NPS 2006). After the Revolutionary War, horse racing and horse breeding spread from Richmond and Norfolk to the northern Piedmont. As the late 19th century northern Piedmont fox hunting industry developed it led to a concurrent rise in horse breeding activity. In 1853 the first Colt Show was held in Upperville to national attention. With the fox hunt, this sealed Upperville as the heart of Horse Country in the Piedmont. “By the 1920s, Fauquier was well established in its new role as Virginia’s ‘Hunt Country.’” (FHS 2008).
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center. “Equestrian activities attracted investment capital that in turn resulted in new growth, including the ‘discovery’ of Middleburg and the preservation of its historic buildings” (NPS 2006). Blue Ridge Farm (next to Rokeby) developed in lockstep with Fauquier’s transition into a popular Hunt Country retreat for wealthy Americans. The property became one of the top breeding farms in Virginia and it may be the oldest continually operated horse-breeding farm in the state (NPS 2006).
GEORGE WASHINGTON FOX HUNTING WITH GEORGE WILLIAM FAIRFAX, nephew of Lord Fairfax. Washington regularly fox hunted with Lord Fairfax. This engraving by Felix O. C. Darley shows the younger relative. Washington aspired to a life like Lord Fairfax’s, and his inability to achieve such a life in part led to rebellion against the crown.
With this, a new wave of northern buyers entered the region in the 1910s and 1920s, picking up old houses and small farms and assembling sprawling estates for horse breeding and fox hunting. The Piedmont’s Hunt Country gained international prominence as a breeding, showing, and riding
With that, finally we reach the Mellon family. Rokeby Farm was purchased as a 441-acre parcel in 1904 by James Oxnard for his brother Henry and wife Marie. He also purchased the adjacent Fountain Hill property (558-acres) to form Blue Ridge Stud. Oxnard’s estate sold the 1002-acre estate to Cary Grayson and Samuel Ross. Upon Ross’s death in 1931 Andrew Mellon purchased the Rokeby side for his wife, and she subsequently sold it to their son, Paul. In 1936 Paul bought Oak Spring, across the road. On it was the Fletcher log cabin (later moved across the road) and he built “The Brick House” with his first wife. Soon after, he acquired many more parcels that eventually totaled the 4000-acre Rokeby Farm. After marrying Rachel Lambert, they built the Oak Spring residence in the early 1950s. Mellon was never able to purchase Blue Ridge Farm/Fountain Hill from Grayson; it remained essentially an inholding among the sprawling Rokeby Farm. Mellon, however, had the foresight beginning no later than the 1980s to protect his lands with conservation easements held by the Virginia Outdoors Foundation.
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Thus, by Mellon-times upper Fauquier County (and Loudoun) had developed into large horse farms and Hunt Country enclaves owned by some of Americaâ&#x20AC;&#x2122;s wealthiest families. With that, we return to the culture of the Piedmont: horses, foxhunts, and all that follows. This story was somewhat predetermined three centuries ago when Thomas 6th Lord Fairfax established himself on the Virginia Frontier in pursuit of the same.
References: Human History Brown, S. E. 1965. Virginia Barron: The Story of Thomas 6th Lord Fairfax. Clearfield. Chambers, B. 1983. Loudoun County Before the Europeans: Indians of the Virginia Piedmont. Loudoun County Historical Society. http://www.loudounhistory.org/history/loudoun-beforeeuropeans.htm Accessed December 10, 2017. Dickonson, J. L. 1959. The Fairfax Proprietary. Warren Press. Egloff, K. and D. Woodward. 2006. The First People: The Early Indians of Virginia. University Press Virginia. Portions available online: https://www.dhr.virginia.gov/arch_NET/timeline/time_line.htm Accessed January 2018. Fauquier Historical Society (FHS). 2008. 250 Years in Fauquier County: A Virginia Story. George Mason University Press.
Groome, H.C. 1927. Fauquier During the Proprietorship: A Chronicle of the Colonization and Organization of a Northern Neck County. Heritage Books. Grymes, C. 2017. Virginia Places. http://www.virginiaplaces.org/index.html Accessed December 2017. (This excellent site was established by a professor at George Mason University.) National Park Service (NPS). 1972. National Register of Historic Places Inventory Nomination Form: Upperville Historic District. https://www.dhr.virginia.gov/registers/Counties/Fauquier/4000064_ Upperville_Historic_District_1972_Final_Nomination.pdf National Park Service (NPS). 2006. National Register of Historic Places Registration Form: Blue Ridge Farm. Dept. of the Interior. www.dhr.virginia.gov/registers/Counties/Fauquier/0300894_BlueRidgeFarmm_NRfinal_2006.pdf Rice, J. D. 2009. Nature and History in the Potomac Country: From Hunter-Gatherers to the Age of Jefferson. John Hopkins. Scheel, E. 2017. Personal Communications at Oak Spring. Scheel, E. 2004. Burning Raid Left Barns, Mills in Ashes. Washing Post November 21, 2004. Accessed December 20, 2017: www.washingtonpost.com/wp-dyn/articles/A64107-2004Nov19.html Schubert, B., and S. Wallace. 2009. Late Pleistocene giant shortfaced bear, mammoths, and large carcass scavenging in the Saltville Valley of Virginia, USA. Boreas 38(3): 482-492.
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CLIP FROM JOHN W ARNER’S 1736-37 MAP OF THE NORTHERN NECK PROPRIETARY granted to Thomas 6th Lord Fairfax. I georeferenced the map so that local place names appear and Oak Spring is shown with a yellow boundary. Oak Spring is located at center in the Mannor (sic) of Leeds – a section Fairfax deemed particularly special and not for sale in the beginning. Fairfax’s house, “Greenway Court,” is on upper left.
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CLIP FROM THE 1755 FRY-JEFFERSON MAP titled: A map of the most inhabited part of Virginia containing the whole province of Maryland with part of Pennsylvania, New Jersey, and North Carolina. The map was created by Joshua Fry and Peter Jefferson, two of the colonyâ&#x20AC;&#x2122;s most accomplished surveyors. This was the definitive map of Virginia in the 18th century. Shown here, what would become Fauquier County is largely empty space on the map. Oak Spring is shown with a star at center. 57
CLIP FROM EUGENE SCHEELâ&#x20AC;&#x2122;S 1996 MAP OF FAUQUIER COUNTY commissioned for The Fauquier Bank. Oak Spring shown with star, Middleburg at right, Upperville in upper left. Note the many Civil War battles and skirmishes (with dates) all along the Ashby Gap Turnpike (Rt. 50).
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Oa k Sp ring ca. 19 37
Barns
Orchard
House
In 1937 Oak Spring contains a functioning farm purchased a year prior by Paul Mellon. The Loughborough barn complex in the northern part of the property existed, and a house existed on the same footprint as the Mellon residence built in 1951. No ponds had been built, but several stonewalls and field boundaries occurred where they exist today. Note the orchard in the western extent. The residence garden wall precisely follows the previous house garden footprint.
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CLIP FROM “SHEET 4 OF 9: UPPERVILLE-FIVE POINTS-RECTORTOWN QUADRANGLE” from “Nine Sheet Map of Upper Fauquier County” by Eugene Scheel commissioned in 1991 by the Virginia Outdoors Foundation and supported by Paul Mellon. Map shows build-dates and proprietors for regional structures among other information.
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MAP ROKEBY FARMS 1994 by Jack Bartenstien. OSGF is at center. Oak Spring has the original copy.
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MAP OF CONSERVATION EASEMENTS (green) held by the Virginia Outdoors Foundation. The Oak Spring Garden Foundation is shown in yellow.
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Eastern redbud (Cercis canadensis) and red maple (Acer rubrum) at Oak Springâ&#x20AC;&#x2122;s forest.
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Oak Spring forest understory suite: Flowering dogwood (Cornus florida); Eastern redbud (Cercis canadensis); Serviceberry (Amelanchier sp.); Spicebush (Lindera benzoin); Pawpaw (Asimina triloba). Watercolors by Autumn Von Plinsky
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260-year old white oak (Quercus alba)
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I NVENTORY AND R ECOMMENDATIONS
Nothing should be noticed. –Rachel Mellon
Oak Spring has 75 rocky outcrops and over two miles of stonewall. Its five ponds, built between 1952 and 1962 capture water released from six springs, all of which eventually trace to Oak Spring’s half-mile of Goose Creek frontage. Trees include 45 native species and nearly four centuries of growth, tying the landscape of today to the days of Thomas, 6th Lord Fairfax. This section describes unique features found on Oak Spring’s 262 acres, and what has been dug up regarding its past. Like the Landscape Context section, it begins with physical features, and then moves to biological components, and ends with cultural features.
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R OCKY O UTCROPS Description The geology of Oak Spring, including the geological history of the site and the specific rock types, was described in the background context section above. This section details the locations, interpretation, and management suggestions for the rock outcrops found on the landscape. Oak Spring contains two general rock types: a 1.1 billion year old metagranite (herein called ‘granite’); and a 570 million year old metadiabase (also called ‘greenstone’). There may be several metegranites or granitic gneisses based on specific composition and/or crystallography. On top of these bedrock types lie several meters of saprolite – chemically weathered rock consisting of fine material, rock fragments, etc.
(north – south). From the outcrops mapped at Oak Spring, it appears 3 or 4 of these linear diabase dikes occur. Granite exposures at Oak Spring are limited to: Peach Tree Lane; two exposures in the Rock Meadows; and large exposures in the forest near Goose Creek. Those exposures on steep slopes are large and form striking cliffy outcrops. Greenstone exposures occur at: the Gateway; Woodland Garden; near Eliza’s Pond; the outlet of Lower Pond; and throughout the Rock Meadows. The map below shows the
Approximately 75 rock outcrops are scattered about Oak Spring. A few form clusters of exposed rocks such as those east of the cemetery and west of the glasshouse. Others are simply small isolated exposures that mostly go unnoticed. Some appear to be large boulders that were moved during field clearance in historical times. The majority of rock exposures at Oak Spring are greenstone. The geological map for Loudoun County (see Geology section in Part 1), shows various metagranites as the dominant country rock, and the diabase dikes as linear intrusions up to 100 meters wide (east – west) and a kilometer or more long
LARGE LICHEN-COVERED DIABASE outcrop in the Rock Meadow.
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locations of all outcrops. At some clusters (e.g. cemetery and gateway) it was not practical to catalog every exposure. The granite and greenstone at Oak Spring do not fit the tidy pattern as those mapped in Loudoun County (just 1.5 miles north). Jim Sawyer, Fauquier County soil scientist who mapped the soils at Oak Spring noted: The geology is a mess. Sometimes the greenstone caps the high points, sometimes it is the gneiss [aka: meta-granite]. Iâ&#x20AC;&#x2122;ve seen [soil] profiles that look like all greenstone, ones that look like granite or gneiss, some that are a blend of the two. Some have greenstone over gneiss, some with gneiss over greenstone, some with alternating layers of greenstone and gneiss.
Animals use the outcrops, mainly in the Rock Meadow. Groundhogs (Marmota monax) dig burrows adjacent to outcrops, presumably for warmth and or stability, as well as vigilance. They have multiple burrows among rocks in the Rock Meadow and can be seen standing vigilant on high points like their alpine cousins (mountain-dwelling marmots). Groundhogs are often scorned as vermin and nuisance, however, when viewed in context of the 14 other species of Marmota in the Northern Hemisphere, all of which inhabit alpine or steppe environments, groundhogs can be appreciated for their unique ecology and adaptability.
The area around Oak Spring appears to have been a dynamic shatter-zone when the diabase intruded the granite. Nonetheless, it makes for an interesting and diverse landscape today.
Importance In addition to providing a glimmer into Virginiaâ&#x20AC;&#x2122;s geologic history, and a confounding puzzle for amateur geologists, the rocky outcrops at Oak Spring provide unique habitat for plants and animals. Lichens and mosses cover larger exposures in the Rock Meadow and Gateway outcrops. With proper management additional sun loving, xeric shrubs and herbs could grow around the edges of the rocks.
TALL GRANITE AND GREENSTONE OUTCROP in the Rock Meadow. This one contains several burrows, lichens, and note the raptor guano on top of the stone.
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Red fox (Vulpes vulpes) has also been observed using burrows in the Rock Meadows. Whether or not they den or just stay cool/warm and safe is unclear. As generalist carnivores, however, they likely keep small mammal populations in check, thereby reducing the tick populations. Raptors, including the Northern Harrier have also been observed using the taller outcrops in the Rock Meadows as perches. Their guano, as well as that from other birds, can be seen on some high points. This serves an ecological function, and creates habitat for orthinocoprophilic lichens (those specific to the nutrients in bird droppings).
maximum visibility by preventing shading and crowding. Tree plantings should stay wide of outcrops. •
Built trails should avoid sensitive rock outcrops (tall rocks, outcrops with burrows, etc.).
•
Consider having the rocks professionally analyzed to determine which metagranites and/or granitic gneiss occur at Oak Spring.
Management Undoubtedly other critters use the rock outcrops found at Oak Spring. Reptiles including snakes use them for sunning, and invertebrates for warming. Specific recommendations for management include: •
Add large rocks in and around ponds for turtles, snakes, and invertebrates.
•
Additional structure around rock outcrops (especially in Rock Meadow) would make them more attractive to animals. Scattered trees (not shading the rocks), and decaying logs, for example.
•
Plants around the edges of rocks should be kept low (or planted with low growing species) to allow wildlife
GRANITE OUTCROP ON PEACH TREE LANE. Note the foliose lichens and mosses, and also the bore hole at right. The purpose of this hole is not clear.
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M eta gr ani te s
M eta di abase
ROCKY OUTCROP EXPOSURES AT OAK SPRING: Pink dots indicate granitic exposures and gray dots indicate diabase/greenstone exposures. Note the three linear alignments of the diabase.
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S OIL Soil is a combination of parent bedrock material, climate, organic matter, and time. The properties of a soil, including its texture, nutrients, minerals, water-holding capacity, and erodability, strongly affect the plants that grow there. This is true for both agricultural plants, and natural plant communities. Early settlers to upper Fauquier County noted the regionâ&#x20AC;&#x2122;s rich and productive soils. They were tipped off to the best sites when they encountered forest communities consisting of walnut and locust (E. Scheel, personal communication). Itâ&#x20AC;&#x2122;s true that both black walnut and black locust prefer neutral or slightly basic soils high in nutrients. Oak Spring contains few locust trees today, but does contain many black walnut trees including several old growth. Soil productivity in the early agricultural days transformed settlers of moderate means into upper-class farmers.
Description In general, soils of the Piedmont region are acidic and low in nutrients. However, the addition of diabase (meta-basalt greenstone) bedrock at Oak Spring adds nutrients, increases pH, and leads to more productive and diverse plant communities. Because Oak Spring soils derive from two distinct rock types (granite and diabase), the soils are at times distinct, or in most areas mixed. The distinct areas would naturally lead to different plant communities with plants that
SOIL PROFILE created by utility work under a stone wall near the Broodmare Barn. Note the stones and fragments known as regolith.
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characteristically grow in nutrient rich sites – like red bud, dogwood, and bitternut hickory – growing more predominantly in the diabase soils, and the plants preferring acidic soils – chestnut oak, black gum, and red maple – growing in the granitic sites. This will be an important consideration for Oak Spring reforestation and other natural areas restoration. Oak Spring commissioned a Type 1 Soil Report from Fauquier County soil scientist James Sawyer in 2017. For the 262-acre property, Sawyer marked 820 GPS points and sampled 290 auger holes (by hand) to examine texture, color, parent material, depth to bedrock, depth to water table, erodability and suitability for various uses such as agriculture, pasture, forestry, septic, etc. (The Type 1 soil survey does not include chemical analysis, however an analysis by Virginia Working Landscapes is included below.) Sawyer’s work includes a soil map and tables (see appendix). He also created a series of maps to show spatially the results of the survey (below). Larger versions of the maps are stored digitally at OSGF. The staging area from pond rehabilitation was not surveyed. Oak Spring contains a number of soil types from the following series: Codorus, Suches, Hatboro, Mongle, Seneca, Variant, Middleburg, Edneytown, Purcerville, Fauquier, Eubanks, Tankerville, Swampoodle, Myersville, Alanthus, Elsinboro, Pignut, Weverton, Catoctin, Peaks, and Philmont. Soils are diverse and include hydric soils, erodible soils, and nice welldrained soils suitable for agriculture and forests.
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Oak Spring Gardens
2A
1 inch = 500 feet
GENERAL SOIL MAP FOR OAK SPRING showing soil types. Numbers reference soil types (see digital appendix). A larger version of this map is stored digitally at OSGF.
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Oak Spring Gardens Parent Material
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OAK SPRING
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GEOLOGIC PARENT MATERIAL (bedrock) as revealed in soils at Oak Spring. A larger version of this map is stored digitally at OSGF.
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Oak Spring Gardens Agricultural Class
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Secondary Cropland Prime Pasture Not Rated Secondary Pasture Not Suited
OAK SPRING
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AGRICULTURAL SUITABILITY of soils at Oak Spring. A larger version of this map is stored digitally at OSGF.
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Oak Spring Gardens Forest Productivity (Hardwoods)
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OAK SPRING
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SUITABILITY OF OAK SPRING SOILS TO HARDWOOD FOREST productivity. A larger version of this map is stored digitally at OSGF.
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Oak Spring Gardens Depth to Water Table
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Type 1 Soiil Report Fauquier County Community Development Department October 13, 2017
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DEPTH TO WATER TABLE in soils types at Oak Spring. A larger version of this map is stored digitally at OSGF.
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Oak Spring Gardens Wetland Potential
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WETLANDS POTENTIAL based on hydric soil indicators at Oak Spring. A larger version of this map is stored digitally at OSGF.
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Oak Spring Gardens Depth to Bedrock
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SOIL DEPTH TO BEDROCK AT OAK SPRING. A larger version of this map is stored digitally at OSGF.
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Oak Spring Gardens Erosion Hazard
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POTENTIAL FOR EROSION on soils at Oak Spring. A larger version of this map is stored digitally at OSGF.
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Chemical Analysis Virginia Working Landscapes, as part of their grassland inventory, conducted soil chemical analysis for three survey plots (Pole A, B, and C below) in the northern and eastern fields at Oak Spring. The table from their report has been copied here and the full report can be found in the appendix. Nutrients and organic matter generally rate moderate to high and pH is slightly acidic.
SOIL SURVEYS
Table 5: 2017 Soil Survey Results at Oak Spring Garden Foundation. These soil samples were processed for VWL by Waypoint Analytical. Values for organic matter and minerals indicate the abundance in the soil sample. Parts per million (ppm) can be converted to pounds per acre by multiplying by two. Pole
Organic matter
P*
K*
Mg*
Ca*
%
Rate
ENR lbs/ acre
A
4.9
M
137
38
M
184
VH
101
M
1108
B
7.4
M
150
33
M
370
VH
230
H
C
4.8
H
134
55
H
152
VH
108
M
Percent Base Saturation
pH CEC** Soil pH
meq/ 100g
K%
Mg %
M
6.1
8
5.9
10.5
69.3 13.8
1116
M
6.1
9.7
9.8
19.8
57.5 13.4
1119
M
5.9
8.3
4.7
10.8
67.4 16.9
ppm Rate ppm Rate ppm Rate ppm Rate
Ca %
H%
* These abbreviations represent chemical elements, Phosphorous (P), Potassium (K), Magnesium (Mg), and Calcium (Ca). **CEC stands for Cation Exchange Capacity and represents the soilâ&#x20AC;&#x2122;s ability to hold nutrients.
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S PRINGS AND S EEPS Description When arriving at Oak Spring for the first time, I asked if there was an actual oak spring. While long-time staff were unaware of a specific Oak Spring, the 263-acre property nonetheless has five significant springs and a possibly a sixth. Regionally, springs tend to lie on east-facing slopes (E. Scheel, personal communication), as they do at Oak Spring. Plat maps from 1841 and 1903 show the propertyâ&#x20AC;&#x2122;s springs, and they were ultimately what drew settlers to this specific spot. The name of the property, apparently coined before 1929, was apt. SPRINGHOUSE AND RUN at spring 1. The run could be planted with low-growing facultative shrubs and herbs.
Spring 1 lies in the springhouse below the residence. The springhouse is Mellon vintage (1950s), however, a previous residence stood on the same house footprint. The original house was likely located there on account of the year round spring that offered pure water and refrigeration. The site therefore may have had a previous springhouse. In 2017 I visually estimated the flow of the spring at approximately 20 gallons per minute (rough estimate). It has considerable volume and empties into Springhouse Pond.
Spring 3 has a large standing water area with wetland species. I was told there was a springhouse at this site historically; a concrete platform, presumably covering a well, and some loose boulders, remain hidden among the vegetation. The combined volume of Springs 2 and 3 appeared (in June 2017) to be similar in volume to Spring 1 at ~20 gallons per minute.
Springs 2 and 3, the Loughborough Springs, lie in the fields immediately north of the barns. They likely drew Nathaniel Lufborough (original spelling) to settle in the early 1800s. Spring 2 appears to be the lower volume of the two. Standing water welcomes wetland obligates including tussock sedges (Carex sp.), rushes (Scirpus sp.), and cattails (Typha sp.).
Though native wetland plants occur, pasture grasses dominate. Other notable native aquatics probably occur, but the pasture grasses were so dense during the inventory that I was unable to see them. The site is mowed periodically, as with the rest of the fields, as moisture levels permit. When wet, tractor tires trench the site.
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Spring 4 is collected from drains in the slopes above (toward library) and a seepage area west of Eliza’s pond with a spring box. It is discharged into the pond via a pipe and stone trench. Willow trees at the road to the Apple House indicate wet conditions. Staff will know more about this system.
acre. They should be treated as such with sensitivity and stewardship. A planting list is provided in Part 3.
Management •
Springs 2 and 3 should be managed as a unique natural area. Add diversity with obligate shrubs to create shrub-scrub habitat, and define the springs’ extent. Exotic pasture gasses can be removed allowing the existing native species to spread. The spring run below springs 2 and 3 can be planted into native shrubs to create shrub-scrub community.
•
At Spring 1, obligate plants can be planted in the spring run between the springhouse and the pond.
•
Planting large specimen trees near springs may cause a reduction in discharge as transpiration siphons water.
The importance of the springs in a hydrological sense cannot be overstated: Spring 1 feeds Spring House Pond, the Tree Shop Pond, and the Lower Pond. Springs 2, 3, and 6 create Wild Pond, then combine with Spring 1 at the Tree Shop Pond, and Lower Pond. Eliza’s Pond is fed by Spring 4.
•
Excavation, fill, or other earthwork should be avoided near springs. Changes in topography and soil can alter spring volume and location. Consider a >100’ buffer.
•
Avoid mowing during wet periods.
The springs have biodiversity value. Because Spring 2 and 3 have an extensive saturation zone with standing water during summer, they may serve as important locations for reptiles and amphibians. With management, these springs may support unique natural communities at Oak Spring. The saturated areas of Springs 2 and 3 are wetlands and total 0.81
•
Document the extent of saturation zone during wet and dry periods. Consider an inventory of wildlife using springs at different times of the year.
•
Consider a hydrological analysis for minerals, contaminants, and flow volume.
A fifth spring occurs in the drainage in the Young Woods. The flow volume appears high relative to the catchment area, suggesting a spring. An old spring box (now dry) occurs part way down the drainage. The spring may have worked into a different discharge point in the drainage from the spring box. Spring 6 is a wet area in the northern corner of Oak Spring. Though it drains to Spring 2, there was no evidence of surface runoff during my inventory. This spring needs additional investigation.
Importance
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Spring 6
Spring 3 Spring 2
Spring 5
Spring 4
Spring 1
L O CATION S O F S IG N IF IC A NT SPR IN G S at O ak S pri ng. B ase map Apri l 2 00 7 le af-off.
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Spring 6
Canada geese (Branta canadensis) at Spring House Pond.
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lakes and ponds in the state are recent human creations. Oak Spring’s ponds are no different, and no less valuable.
P ONDS Description The five ponds are Oak Spring’s crown jewels. These are the places where the mood of the day is reflected back to you. They’re the places with animated activity from birds, turtles, and dragonflies. These places are where people will want to congregate, and also to be alone. With the exception of Eliza’s Pond, the other four ponds don’t have universally accepted names. They’ll be named here for ease of discussion, but they should be given proper names that reflect Oak Spring’s history, creativity, and landscape. The map below details the names and locations.
According to aerial imagery, none of Oak Spring’s five ponds were present in 1937. By 1952 (next available imagery), after the Mellon’s arrived, the Spring House pond was in place, and the Tree Shop pond was being constructed. Between 1952 and 1957, Wild Pond and Eliza’s Pond were added. The Lower Pond was built between 1965 and 1969. In 2016-2017 the ponds were rehabilitated as follows: 2016-17 REHABILITATION WORK ON OAK SPRING’S PONDS. Pond Eliza’s Pond
Work New input from source; spillway to Tree Shop Pond
Spring House New input from spring; dam; spillway; dredged DIMENSIONS OF OAK SPRING’S 5 PONDS. Pond
Area
Depth
Perimeter
Spring House 0.31 acre 0.13 ha
420’
130m
Tree Shop
2.2 acres 0.89 ha
1240’
380m
Wild Pond
1.4 acres 0.57 ha
950’
290m
Eliza’s Pond
0.24 acre
0.10 ha
370’
112m
Lower Pond
2.6 acres 1.05 ha
1700’
520m
H ISTORY Unlike glaciated regions farther north, Virginia has only two natural lakes: Lake Drummond (in the Great Dismal Swamp) and Mountain Lake (Giles Co.). All the remaining thousands of
Tree Shop
Dredged; rehabilitated dam and spillway
Wild Pond
No work; left alone
Lower Pond
Rehabilitated dam and spillway
M ARGINS Today four ponds have margins that are mowed to the edge. Eliza’s, Springhouse, and Tree Shop have regularly maintained grass mowing, while Lower Pond is bush hogged. Wild Pond is unmaintained with dense cover of shrubs around the margin. Lower Pond has sporadic shrubs on the margins. The other three have no shrubs on the margins.
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Wild Pond Elizaâ&#x20AC;&#x2122;s Pond
Tree Shop Pond Spring House Pond
Lower Pond
PONDS AT OAK SPRING. Image is June 2011 prior pond rehabilitation in 2016-17. Blue areas show springs and runs, green areas are inlet wetlands.
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Tree Shop Pond and Lower Pond have wetlands at the inlets. At Tree Shop Pond this wetland occurs at the end of the Springhouse run. It’s composed of willows, and a variety of native and exotic shrubs and herbs. The inlet wetland at Lower Pond also contains willows, as well as cattails, and exotic yellow flag iris. The rarity of these environments makes them valuable natural communities that warrant stewardship. They are shown as green on the map. A QUATIC E COLOGY The aquatic environments in Oak Spring’s ponds were not surveyed and are thus poorly understood. Animal species observed include: Amphibians Leopard frog, green frog Reptiles Painted turtle, snapping turtle, northern water snake Fish
specific ecological survey and plan by an aquatic ecologist may be desired if this fits Oak Spring’s goals. Such a plan should specifically address treatment of algae and duckweed, and eradicating fish populations from the small ponds.
Importance Oak Spring’s farm ponds make an unquantifiable contribution to the dry uplands of Virginia Piedmont. Their ecological value and aesthetic value ranks as high as any Oak Spring asset. If properly managed, ponds add species richness to the landscape. They do this currently, but with additional management – by planting shrubs, graminoids, and herbaceous species on the margins, and aquatic plants in the ponds – they will become all the richer. Microscopic, macroscopic, and larger vertebrate animals, and the vegetation they depend on, will form a rich focal point for Oak Spring guests. Add to this the scenic and recreational values as well as the ecological research potential and the ponds become one of the greatest assets Oak Spring has.
Channel catfish, bluegill, perch, large mouth bass
Management
Osprey, Canada Geese, Mallard, Tree swallow, Killdeer, Spotted Sandpiper
The goal of pond management at Oak Spring should be to: increase native diversity; create wildlife habitat; reduce longterm management costs; and enrich the visitor experience. To that end, consider the following management actions:
Birds
The ponds may have exotic aquatic plant species such as Eurasian water milfoil (Myriophyllum spicatum) and others. It may not be feasible or justified to eradicate these. A pond-
•
Clear exotic vegetation from the margins of Wild Pond. Consider gradual clearing of the dam as large woody plants can be detrimental to pond dams.
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•
•
•
•
•
Plant pond margins with a hedge of native shrubs and herbaceous plants. A species list is provided below as an initial guide. Each pond will need a planting plan, which could be done in collaboration with a landscape architect. Marginal plants will help control geese. Part 3 contains a complete species list.
SPECIES LIST FOR WETLANDS, spring runs, and pond margins planting. A complete list is provided in Part 3. Common Name
Species Name
Sweetflag
Acorus calamus
Spikerushes
Eleocharis spp.
Green bulrush
Scirpus atrovirens
Add emergent and aquatic plants such as waterlilly (Nuphar sp.), Arrowhead (Sagittaria sp.) and arrow pickerelweed (Pontedaria cordata). See Helfrich et al., 1981 for species and ecology.
Cattails
Typha spp.
Joe pye weed
Eupatorium fistulosum
Smooth alder
Alnus serrulata
Winterberry holly
Ilex verticilata
Eliminate fish in Springhouse, Eliza’s, and Wild Ponds. (Leaving fish in Tree Shop and Lower Ponds.) Elimination of fish will allow amphibians, reptiles, and invertebrates to thrive. Fish can be eliminated through shocking and capture or chemical treatment.
Spicebush
Lindera benzoin
Highbush blueberry
Vaccinium corymbosum
Southern arrowwood
Viburnum dentatum
Silky dogwood
Cornus amomum
Elderberry
Sambucus canadensis
Boulders and/or logs added to pond edges increase structural diversity and complexity. Reptiles and amphibians will use island rocks for basking and underwater organisms will utilize the added structure. Boulders placed in the shallows of each pond create opportunities for turtles, snakes, and the people who watch them. Wild Pond has rocks already.
Swamp rose
Rosa palustris
Buttonbush
Cephalanthus occidentalis
Swamp white oak
Quercus bicolor
Black gum
Nyssa sylvatica
River birch
Betula nigra
Black willow
Salix nigra
Bald cypress
Taxodium distichum
Monitor duckweed and algae problems and consult an aquatic ecologist about treatment options.
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•
•
In 2017 the Canada geese population was overabundant on Springhouse and Lower Ponds. Overabundant geese alter pond ecology through added nutrient loads. High geese populations are a management issue in many places. People deal with them using dogs, noises, culling, etc. Shrubs and tall grass around the margins should reduce the population as geese prefer unfettered access to pond margins. Incorporate the ponds into a recreation plan with thoughtful siting of trails and sitting areas and the interface of those with plantings and watchable wildlife. People will be drawn to the ponds.
•
Build an Osprey platform in the middle of the north shore at Lower pond. This location – in conjunction with the trail plan in this document – will allow the birds privacy. Osprey have been observed fishing in Wild Pond and Tree Shop Pond. Lower Pond will be the quietest as it is farthest away from residences and other activity.
•
Complete a baseline study of water quality including pH, dissolved oxygen, nitrates, phosphates, biological oxygen demand, turbidity, temperature, macroinvertebrates, and other basic biological parameters.
Resources Helfrich, L. et al. 1981. Common Water Plants of Virginia. Virginia Cooperative Extension Service. https://vtechworks.lib.vt.edu/bitstream/handle/10919/47751/VCE42 0_844.pdf?sequence=1 DNREC. 2017. Osprey Nest Platforms: Guidance for Placement. Delaware Natural Resources and Environmental Control. http://www.dnrec.delaware.gov/fw/NHESP/Documents/Osprey%20 Nest%20Platform%20Guidance.pdf Piedmont Environmental Council. 2008. Common Wetland Plants of Northern Virginia’s Piedmont: A Field Guide. https://www.pecva.org/library/documents/ResourcesPublications/Publications/Plant-Wildlife/WetlandPlantGuide.pdf
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Goose Creek at Oak Spring.
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G OOSE C REEK : AKA , C OKONGOLOTO Over two-thirds of a mile of Goose Creek meanders through Oak Spring as a hidden jewel. The 3,500 feet of creek provides pools, riffles, community and species diversity, and of course contemplation and calm. Here one can seek out freshwater mussels, watch kingfishers, or launch a canoe and paddle to the Potomac.
Description Goose Creek is a 54-mile long stream, rising at Manassas Gap on the Blue Ridge and emptying into the Potomac River. From Manassas (elevation 905 feet), the creek drops steeply 600 feet over 10 miles before it flattens and meanders along the Fauquier County Piedmont and Loudoun Valley. It cuts through Catoctin Mountains near Oatlands, Virginia and empties into the Potomac River (elevation 190 feet), east of Leesburg. There is one dam on Goose Creek, approximately four miles up from the Potomac. Oak Spring lies in the Upper Goose Creek watershed at mile 16.5 (elevation 375 feet) from Manassas Gap. Below Oak Spring, Goose Creek flows 37.5 stream miles to its confluence with the Potomac River. In 2013 the Goose Creek Association, in partnership with Virginia Department of Environmental Quality, conducted a water quality survey throughout the watershed. Overall water quality was good with high marks for dissolved oxygen, pH,
water temperature, and total phosphorus. Total nitrogen was moderate and benthic macroinvertabrate quality was poor. In Upper Goose Creek, however, macroinvertebrates scored fair. Bacterial levels (E. coli) in Upper Goose Creek were moderate and tend to spike after rains (especially heavy rains) as pollution from the land runs into the creek. Regionally, Goose Creek showcases a handful of special places. A bridge over Goose Creek on the old Ashby Gap Turnpike (one mile from Oak Spring) was the site of a Civil War battle in 1863. The bridge was built between 1801 and 1803 and is the largest stone bridge in Virginia. According to Eugene Scheel, regional historian par excellence, the name Goose Creek is written on old maps and derives from an Algonquin language name: Goose Creek, the largest Loudoun tributary of the Potomac, was called "Cokongoloto," meaning "creek or stream of geese or swans." (Scheel 2017).
Hydrology and Behavior The United States Geological Survey (USGS) maintains a gauging station on Goose Creek near Middleburg (station 01643700). This is the nearest station to Oak Spring and no station occurs further upstream. Downstream, an additional station occurs near Leesburg. The Middleburg Station has recorded hydrological data on Goose Creek since 1965. I
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have summarized a few data sets here. (The gauging station data can be viewed in real time on the web.)
of forest also contribute to increased runoff and stream flow. Regionally, impervious surfaces are likely increasing, though at a marginal rate. Forest cover is low in the Goose Creek watershed and has changed little during the 20th century, perhaps increasing slightly.
SEASONALITY The table below outlines the mean discharge (in cubic feet per second) for each month of the year. During the month of January, Goose Creek at Middleburg averages 166 ft3/s. February through April tend to have the highest average flows on Goose Creek, while July to September tend to be the lowest. This is typical for most eastern streams.
MEAN MONTHLY DISCHARGE (ft /s) near Middleburg 1965-2017 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov 166 193 241 217 186 124 53 42 68 82 91
Nonetheless, if discharge rates are increasing, Oak Spring can expect higher flows and subsequently greater pressure on stream banks and floodplains.
Mean Annual Discharge (G3/s) of Goose Creek (at Middleburg) 1965-2016
3
Dec 150
350 300 250
Flow Trend
200 150 100
2015
2012
2009
2006
2003
1995
1992
1989
1983
1986
1980
1977
1974
0
1971
50 1966
MEAN DISCHARGE The next graph shows mean annual discharge from the same station. The average flow for each year is presented on the blue line. Note the peak in 2003 at 301 cfs. The year was skewed by Hurricane Isabel, which ushered in Goose Creekâ&#x20AC;&#x2122;s highest recorded flow at 23,000 cfs. Also note 2002 was an exceptionally dry year. A trend line is added in green. It shows a pattern of increasing flows over the past 50 years. The increase in flow on Goose Creek could be due to a variety of factors. It could simply be a result of increased precipitation. Precipitation is increasing (National Climate Assessment 2014). But increased impervious surfaces and loss
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PEAK FLOW Like mean discharge, peak events on Goose Creek – the largest flood event of the year – occur more often in February, March, or April. September, October, and November have the fewest peak flows. However, the most extreme flows occur in the fall as a result of Atlantic hurricanes.
Peak Flow (G3/s) Each Year, Goose Creek at Middleburg 25,000
Peak Flow
20,000
Trend
15,000 10,000
0
1966 1971 1974 1977 1980 1983 1986 1989 1992 1995 2003 2006 2009 2012 2015
5,000
Date Event Discharge Precipitation* 2003, Sept. 23 Hurricane Isabel 23,000 cfs ~5 inches 1972, June 22 Hurricane Agnes 19,200 cfs ~10 inches 1976, Oct. 9 Unnamed storm 16,600 cfs ~8 inches** 2012, Oct. 30 Hurricane Sandy 15,100 cfs ~6 inches * Approximate Precipitation amounts based on NOAA storm maps and ** Yohn (2011).
TEMPERATURE Like most streams, Goose Creek has a predictable diurnal temperature variance and a seasonal temperature variance. This affects the behavior of aquatic organisms just as temperature does for terrestrial organisms. (This USGS data set was limited, lacking Jan. and June and only 2-3 years data.) Temperatures are in °C: MEAN WATER TEMPERATURES seasonally near Middleburg. Feb Mar Apr May Jul Aug Sep Oct Nov 3°C 8.1°C 12°C 18°C 25°C 22°C 20°C 13°C 7°C
Dec 4°C
Inventory The four highest events on Goose Creek since 1966 occurred in the following years from the following events in the table below. For perspective, the average discharge of the Potomac River is 11,600 cfs, and the Hudson River is 21,000 cfs. These large flow events shape and redefine Goose Creek and its floodplain, channel, cut-banks and point bars, and bottomland vegetation.
A complete aquatic inventory of Goose Creek was beyond the scope of this project. Nonetheless, incidental observations revealed a variety of birds (see bird list in the Wildlife section). Sightings include nesting bald eagles in 2017 (across the stream in the tall white pine) suggesting good water quality. A number of fishes could be seen in the water, and one mussel. The mussel is an Elliptio sp., possibly E. fisheriana, however,
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the taxonomy of this genus is confusing and under constant revision. It is surprising to see limited published work describing Goose Creek. I expected information on fisheries, ecology, and geomorphology to be readily accessible. I reached out to Goose Creek Association for information. They confirmed my observation and have not commissioned any studies. The Oak Spring section of Goose Creek begins at its upstream end with a broad bottomland as it meanders around to the north and east. In this section the riparian strip is narrow and dominated by box elder, with red maple, sycamore, hackberry, black walnut, ash, musclewood, and farther away bitternut hickory. The creek turns from east to north at a scenic cliff on the far side. Around the bend, the steep slope section contains only a narrow strip of riparian vegetation between the trail and the creek itself. Vegetation is described with more detail in the Vegetation section. It’s worth noting the early deeds from 1810s also listed “crabapple tree” occurring “on the bank of Goose Creek.” The open meander section contains the remains of what appears to be an old stone ford (photo). Stones cross the stream in straight lines as a hardened crossing. On the far side (off Oak Spring property) after crossing the bottomland, a path goes up a small draw to the uplands. It is likely this upland path was connected to the ford. I’ve found no reference to this ford in documents or maps.
OLD GOOSE CREEK FORD: Appears to be an old stone ford crossing Goose Creek. Oak Spring in this image is on the far side.
Management and Recommendations Oak Spring should initiate a water quality monitoring program. Such an initiative could be done in partnership with the Goose Creek Association. Because nearly 20% of the Goose Creek watershed occurs upstream of Oak Spring, OSGF is limited in doing large-scale improvements to water quality or connectivity. However, with 3,500 feet of creek frontage, Oak Spring can address conservation goals on its stretch of stream.
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The best thing Oak Spring can do for the creek is to reforest the riparian and bottomland. This is described with more detail in the Management section, however, below is a map showing the 5.1 acres of bottomland reforestation potential.
GOOSE CREEK BOTTOMLAND AT OAK SPRING. The blue area represents 5.1 acres of Goose Creek floodplain that should be reforested with the addition of 3,000 trees and shrubs.
UNDERREPRESENTED SPECIES along Goose Creek bottomland at Oak Spring. See Part 3 for greater detail on Goose Creek Bottomland restoration and reforestation. Common Name
Species Name
Red maple
Acer rubrum
Silver maple
Acer saccharinum
Smooth alder
Alnus serrulata
River cane
Arundinaria sp.
Pawpaw
Asimina triloba
River birch
Betula nigra
Winterberry holly
Ilex verticilata
Spicebush
Lindera benzoin
Sweetgum
Liquidambar styraciflua
Tulip poplar
Liriodendron tulipifera
Cucumber tree
Magnolia acuminata
Sweetbay magnolia
Magnolia virginiana
Black gum
Nyssa sylvatica
Sycamore
Platanus occidentalis
Eastern cottonwood
Populus deltoides
Swamp white oak
Quercus bicolor
Pin oak
Quercus palustris
Black willow
Salix nigra
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References USGS National Water Information System: 01643700 Goose Creek Near Middleburg, VA. 2017. https://nwis.waterdata.usgs.gov/nwis/inventory/?site_no=01643700 &agency_cd=USGS National Climate Assessment. 2014. Heavy downpours increasing. http://nca2014.globalchange.gov/report/our-changingclimate/heavy-downpours-increasing Scheel, E. 2017. Indians left their mark in naming landmarks in Loudoun County. Accessed November 25, 2017. http://www.loudounhistory.org/history/indians-loudoun-names.htm Yohn, J. 2011. Flood Flashback: 35 years after the great deluge, memories rise. The Fredrick News Post. Accessed November 27, 2017. https://www.fredericknewspost.com/archive/floodflashback/article_a8907abd-8ead-5abb-b180-84fc1ed61684.html
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V EGETATION The vegetation at Oak Spring has formed as a result of three nested scales of ecological change. First, tens of millions of years of evolutionary history has given us the temperate deciduous forest of eastern North America (see background context). Second, thousands of years of American Indian land use has shaped the northern Virginia Piedmont into the oakhickory forest, woodland, and savanna of presettlement times. Finally, a couple centuries of European land use and a few decades of Mellon era management put the most recent level of ecological change with extensive clearing, faunal extinctions, and species introductions into what we find today. This section outlines Oak Springâ&#x20AC;&#x2122;s natural communities, vegetation, and trees.
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Flora and Natural Communities Virginia’s flora has affinities with several floristic regions as the species composition of the state pulls from areas to the west, the north, and beyond. Weakley et al., (2012) breaks the flora of Virginia into six biogeographic groups (shown as a percentage of Virginia’s total flora): Southern, 32%; Widespread, 21%; Northern, 18%; Western, 5%; Narrowly Appalachian, 5%; Nonnative, 19%. Together, those groups (except nonnative) collectively compose Virginia’s 2,558 species of native plants. This compares regionally with West Virginia at 1,739 species, Pennsylvania’s 2,076 species, and 3,251 species in North Carolina (Weakley et al. 2012). Virginia ranks 13th among the 50 states for plant species richness. Described by Weakley et al. (2012), Virginia’s Piedmont vegetation generally falls into two upland forest communities: a drier nutrient-poor type that fosters Oak-Heath communities, and a mesic and basic soil type supporting OakHickory forest communities. By this construct, Oak Spring falls in the latter group as no heaths are found and hickory trees – especially mesic site indicator bitternut hickory – are abundant. Clearly Oak Spring has some acidic soils that derive from old granitic rocks and corresponding acidic species (black gum, Liriodendron, and red maple, for example). But Oak Spring’s diabase is more dominant and more indicator species suggesting this soil are present. Nonetheless, soil
chemical analysis performed by Virginia Working Landscapes indicates soils are slightly acidic (see Soils section in Part 1). Spira (2012) describes Piedmont plant communities in broad terms splitting uplands into two groups: a more acidic OakHickory Forest and a Basic Mesic Forest. Using the species lists as a guide, Oak Spring emerges as a hybrid of Basic Mesic Forest and Oak–Hickory Forest. From the relatively small amount of native vegetation at Oak Spring (the woodlands), tree species tend to align with Oak–Hickory Forest, but shrubs and herbaceous plants align more closely with Basic Mesic Forest. Oak Spring’s mix of acidic granite rocks and more basic basaltic rock probably accounts for the distinction. (That, and Spira takes a very broad approach as many subtle distinctions could be made in community composition.) Nonetheless, the species lists are useful for future management recommendations. Those will be addressed in Part 3. The Virginia Department of Conservation and Recreation (DCR) Natural Heritage division, like most states, has created a classification system for natural communities (Fleming et al. 2017). This system contains many more classifications than the simple breakdown offered by Spira (2012) or Weakley (2012). Fleming et al. (2017) identify natural communities defined by multifactor biophysical parameters including geology, soil nutrients, topography, elevation, hydrology, and disturbance regime. They note: “Plant species are faithful indicators of site conditions, and plant species collectively (i.e. vegetation)
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reflect the biological and ecological patterns across landscapes” (Fleming et al. 2017). Among the terrestrial group – Low-Elevation Dry and DryMesic Forests, the Basic Oak-Hickory Forest community type specifically describes regions around, and including, Oak Spring on account of its diabase bedrock. Fleming et al. state: The principal habitats for Basic Oak-Hickory Forests in Virginia are submesic to subxeric uplands over basic igneous and metamorphic rocks such as diabase, gabbro, amphibolite, and metabasalt (greenstone). Soils range from moderately acidic to circumneutral and have moderately high levels of calcium, magnesium, manganese, iron, and aluminum. The term "basic," as applied by DCR-DNH ecologists, refers high levels of base cation saturation rather than to soil pH, which analysis has proven to be a less reliable indicator of fertility and parent material. Communities in this group are scattered to locally extensive throughout the Virginia Piedmont.
The representative species list provided by DCR is a close approximation to Oak Spring’s forested slope. The list of trees and spring ephemerals places Oak Spring in this community type and provides a fine starting point for restoration (Part 3). Fleming et al. (2017) also list Acidic Oak–Hickory Forests as an intermediate between the Basic Oak–Hickory listed above and a poorer Oak–Heath Forest. While there is overlap, and the species list for Acidic Oak–Hickory could also serve restoration efforts at Oak Spring (especially in granitic areas), the geology and plants present indicate richer conditions of the basic forest community type.
The bottomland of Goose Creek contains a distinctly different community than the uplands. Gone are white oak, black gum, most hickories, and spring ephemeral flora. In exchange, the flood-prone bottomland offers sycamore, box elder, musclewood, and wingstem. Fleming et al. describe this community type as Piedmont-Mountain Small Stream Alluvial Forest. Periodic, seasonal flooding of Goose Creek drives the community. Flood tolerant species dominate by the bank, while less tolerant species thrive on rich bottomland soils on slight rises farther away.
Virginia DCR Natural co mmunity types at Oa k Spring: Basic Oak – Hickory Forest Piedmont Small Stream Alluvial Forest
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Vegetation Inventory Oak Spring’s vegetation was sampled seasonally in 2016-17 to capture the diversity and variety of flora occurring on site. This was not a quantitative inventory, nor was it a botanical inventory; rather it is a survey of general patterns in vegetative community composition, structure, substrate, land use history, and successional trends. This information forms the basis for management planning in Part 3. This section provides an inventory of Oak Spring’s natural vegetation, its 638 open grown trees, and places the site into a natural communities context (above). Descriptions of exotic species occur in the next section.
Description The map at right shows Oak Spring and its eight vegetation compartments. These areas were differentiated largely on woody species composition which itself is largely a function of disturbance history. Each compartment is described below with characteristics of composition, stand age, management concerns, and future potential. The bulk of the property is open pasture/grassland with concentrations of scattered trees. Oak Spring has 638 individual trees in the open areas. These range from 60-inch diameter 260-year-old white oaks, to one-inch diameter apple trees planted last year. The Tree Inventory follows the vegetation descriptions.
VEGETATION COMPARTMENTS AT OAK SPRING: █ Young Woods
█ Spring Branch
█ Old Woods
█ Woodland Garden
█ Weedy Pasture Woods
█ Pond Inlets
█ Goose Creek Bottomland
█ Open Grasslands (no color)
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█
YOUNG WOODS (8.9-ACRES)
The Young Woods are named for their recent emergence from abandoned pasture in the early 1970s. A few older red oaks, two old tulip trees and others grew low in the ravine prior to abandonment. The transition likely resulted from a switch to haying as no sign of a fence occurs. Old aerial photographs confirm this. The smaller compartment (see map) has the same history and similar composition. The compartment is dominated by black walnut and ash originating in the 1970s. Other tree species include black cherry, musclewood, red oak, and young hickories. The shrub layer is dominated heavily by coralberry (Symphoricarpos orbiculatus), with occasional black-haw and native Rubus spp. Oak Spring’s only witch hazel (Hamamelis virginiana) occurs in this area near the old Liriodendron. Exotics are dense with multiflora rose and Japanese stilt grass dominating, with Japanese honeysuckle, wine berry, and a few trifoliate orange of Mellon origin. A stand of Ailanthus was eradicated in 2017. Other herbaceous species are generally ruderal and patchy and include nettles, woodland knotweed (Polygonum viginianum), Christmas fern (Polystichum acrostichoides), white wood aster (Eurybia divaricata), Smilax sp., Viola sp., and poison ivy among others. The compartment is bound by an original stone wall on the north, and a masonry stone spring box occurs along the drainage. The vegetation reflects the site’s pastoral history.
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OLD GROWTH (4.7-ACRES)
The Old Growth compartment is named for the remarkable structure of trees over 200-years in the canopy. Trees up to 320 years were confirmed through coring. At nearly 5 acres, this is a significant natural feature for Oak Spring and Upperville more broadly. It is old, and it is diverse. Nonetheless, it has problems with exotic plants. A lot of diversity is packed into this small compartment. Tree species include white oak, northern red oak, black walnut, hackberry, bitternut hickory, shagbark hickory, pignut hickory, white ash, eastern redbud, serviceberry, flowering dogwood, blackgum, American beech, eastern red cedar, post oak, black cherry, and American elm â&#x20AC;&#x201C; impressive tree diversity for a small parcel. White oaks were cored and are interpolated to 290 years, post oak to 320 years and black gum to 200 years. Scattered shrubs include pawpaw, black-haw viburnum, spicebush and Smilax. Exotics fill in most of this layer. Native herbaceous plants are largely outcompeted by exotics. A lingering spring ephemeral bloom, however, has potential to recolonize. Species include: Yellow Corydalis (Corydalis flavula); Bloodroot (Sanguinaria canadensis); Cut-leaf toothwort (Dentaria lacinata); Trout lily (Erythronium sp.); Spring beauty (Claytonia virginica); Virginia bluebells (Mertensia virginica); Rue anemone (Anemonella thalictroides); May apple (Podophyllum peltatum) and Viola sp. (My window for noting spring ephemerals was limited to early April; additional species likely occur).
Additional native herbaceous species include white wood aster, Christmas fern, wingstem (Verbesina alternifolia), yellow wood-sorrel (Oxalis stricta); pokeweed (Phytolacca americana), woodland knotweed, Viola spp., Impatiens sp., unknown asters, and a number of unknown grasses and sedges. Exotic species dominate most of the ground cover. Japanese stilt grass is the primary exotic, with multiflora rose secondary. Stiltgrass is so thick in some areas no other species are present. Garlic mustard and Japanese honeysuckle are common and patchy. Exotic trees include a few sweet cherry (Prunus avium) and Norway maple (Acer platanoides).
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Bedstraw (Galium aparine), common chickweed (Stellaria media), ground ivy (Glechoma hederacea), and common speedwell (Veronica persica) mix with native and exotic ground flora.
Steep slopes in this compartment permitted its persistence. It is shown on Robert Fletcherâ&#x20AC;&#x2122;s 1841 will plat as forest. None of the trees suggest formerly open landscape, and there are no basal scars to suggest a previous fire. Red cedar suggests the site was at once more open, but not much. A stone fence on the north side also suggests domestic animals foraging in woodlands. The lack of old fallen trees (there are recent fallen trees) indicates trees were removed when they fell. The lack of stumps indicates there has been no cutting in at least 50 years. The lack of regenerating trees and the dominance of exotics is a symptom of overabundant deer. Nevertheless, Virginia Working Landscapes photographed a bear in the forest in 2017. The site has huge potential.
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FOREST EPHEMERALS: Clockwise from upper left: trout lily (Erythronium sp.); Virginia bluebells (Mertensia virginica); rue anemone (Thalictrum thalictroides); spring beauty (Claytonia virginica); corydalis (Corydalis sp.); bloodroot (Sanguinaria canadensis).
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█
WEEDY PASTURE WOODS (3.1-ACRES)
This compartment is an extension of the Old Growth as it continues on the same slope. However, it has a different disturbance history that has resulted in a different plant community. The stand is younger and it is weedier. There is a fairly distinct line separating the two communities. Trees in this small compartment include younger red oaks, bitternut and pignut hickories, black cherry, hackberry, black walnut, honey locust, white ash, serviceberry, and redbud. While there are a few black-haw viburnum, some Smilax sp., Rubus sp., and coralberry in this stand, the compartment is overrun with multiflora rose and Japanese honeysuckle. A number of English Ivy vines grow thick in the trees, but most were eliminated in 2017. The herbaceous and ground layer is best described as “cosmopolitan weed flora.” Japanese honeysuckle is a heavy dominant, with rose, stiltgrass, and others. There are a number of native sedges and grasses. Remains of a small original stone wall section lies on the top of the slope. Most of this wall was removed and placed at the base of the Lower Pond spillway in 2017. However, some stones can be seen still. The compartment was more open than the Old Growth section during agricultural era. Succession is estimated at 100 years or slightly more.
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GOOSE CREEK BOTTOMLAND (6.6-ACRES)
The Goose Creek bottomland at Oak Spring is a small, but diverse open riparian corridor. When measured linearly, this compartment runs 660 meters (0.40 miles) along Goose Creek. Diversity of trees is probably lower than in the old growth area, but herbaceous plant diversity might be highest in this compartment. As evidenced by barbed wire and stone work on the bank, this area has been subjected to grazing historically, and it is periodically flooded from Goose Creek. In terms of relative abundance, trees include: box elder, American sycamore, red maple, bitternut hickory, ash, black walnut, hackberry, with lesser amounts of Osage orange, musclewood, and red oak. Two stands of pawpaw occur in the middle of the compartment, and vines Smilax sp. and poison ivy are common. Japanese honeysuckle is thick, and multiflora rose is uniformly scattered. Herbaceous plants include: wingstem (dominant), goldenrod, Joe pie weed, stinging nettle, Gallium sp., Impatiens sp., nut sedge, woodland knotweed, Persicaria sp., Phlox sp., and numerous unknown grasses and sedges including abundant Virginia wild rye (Elymus viginica). Trout lily and ivy-leaved morning glory both occur in small numbers. Water willow (Justicia americana) is abundant close to the water. This compartment has great potential, especially with the addition of river cane (Arundinaria sp).
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WOODLAND GARDEN (1.4-ACRES)
The Woodland Garden section is named for its potential as a future woodland garden site. The compartment includes the narrow band of woodland from the hilltop near the tractor barn, down to Spring Branch below Tree Shop Pond. It also includes the ravine between the two larger ponds. An original stone fence runs north-south down the slope, and the stream includes a small bedrock waterfall with nice scenic potential. Species composition reflects the parcelâ&#x20AC;&#x2122;s history as old woodland pasture on rich soils. Three presettlement white oaks occur in the compartment (one is dead and another is almost dead). These are impressive, open-grown trees approximately 250 years old. The successional woods are mixed hardwoods with no dominant. Red oaks, species of hickory, hackberry, black cherry, and others occur. One 5-inch diameter hickory was cored to ~1920s. Most young trees likely date to this time of wood-pasture abandonment. Spicebush (Lindera benzoin) dominates the narrow strip on the slope paralleling the stone fence. Rubus sp. is occasionally seen, and Impatiens sp. grows thick along the stream. Except for a number of unknown grasses and sedges, most of the remaining plants in the lower layers are exotic. These include: multiflora rose, garlic mustard, shrub honeysuckle, Euonymus alatus, wineberry, and yellow flag iris (Iris pseudacorus) along the stream banks. This is a beautiful area with huge potential to become a highlight of Oak Spring.
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SPRING BRANCH (2.4-ACRES: UPPER; 2.1-ACRES: LOWER)
The main drainage system at Oak Spring is labeled Spring Branch on Robert Fletcher’s 1841 plat in his will. Here I’ve separated Spring Branch into a lower unit (Lower Pond to Goose Creek) and upper unit (around Wild Pond to Woodland Garden). The vegetation in the two compartments is similar. In general, the lower unit is more strongly associated with bottomland vegetation, while the upper unit is somewhat upland oriented. Lower Spring Branch is dominated by hackberry, sycamore, ash, black walnut and box elder. Upper Spring Branch is similarly composed, however, without sycamore and box elder, and with the addition of black cherry, pin oak, persimmon, white mulberry, and other upland species. Willows are occasionally found in both. Upper unit is heavily dominated by Japanese honeysuckle with multiflora rose, some shrub honeysuckle, oriental bittersweet, privet, wineberry, and more. Other than Rubus sp., Smilax sp., poison ivy, goldenrod (Salidago sp.), asters, wingstem, pokeweed, and other ruderal plants, natives are hard to find. A few trees in the lower unit were present in the 1950s. Most of the vegetation has initiated since the 1970s and 80s (lower) and 1980s and 90s (upper). Much of this area is slated for exotics removal in 2018.
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POND INLETS (0.1-ACRE: LOWER POND; 0.2-ACRE: SHOP POND)
These two small compartments contain wild arrivals and form unique wetland communities at the inlets of Oak Springâ&#x20AC;&#x2122;s two larger ponds. With removal of exotics and additional plantings to add diversity, they have huge potential as unique natural areas. The site on Lower Pond is quite small. An additional site is located at the north inlet to Tree Shop Pond. These sites are difficult to penetrate because of thick vegetation and standing water, thus the list here is brief. Willow (Salix nigra) is common. Yellow flag iris, and various rushes, sedges, and grasses occur in sun-exposed areas. The Tree Shop Pond area contains a number of exotics including Japanese honeysuckle, rose, and Ailanthus. This area is a tangle. The potential of these areas for adding diversity and richness to Oak Spring is huge. They are more fully explored in Part 3.
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OPEN GRASSLANDS (190-ACRES)
While about 30 acres of Oak Spring occurs in the natural vegetation listed above, and about 40 acres are buildings and mowed grounds, the majority is open grassland, also known as hayfield, meadows, etc. If left undisturbed, vegetation would slowly succeed to communities resembling the Weedy Pasture Woods and the Young Woods. Presumably these areas were originally forest, savanna, or woodland. Over the past 200-years, they have been agricultural, most recently for hay or horses. Virginia Working Landscapes surveyed three sites within this broad complex for plant, invertebrate, and bird diversity. Their plant inventory is summarized here: The 13 most abundant species making up ~75% of occurrences include (Bold species are native; * introduced; ** invasive): tall fescue (Lolium arundinaceum*); Kentucky bluegrass (Poa pratensis*); Carolina horsenettle (Solanum carolinense); Orchardgrass (Dactylis glomerata*); longleaf groundcherry (Physalis longifolia); Piedmont bedstraw (Galium pedemontanum*); white clover (Trifolium repens*); nim blewill (Muhlenbergia schreberi); narrowleaf plaintain (Plantago lanceolata*); woodsorrel (Oxalis sp.); Dandelion (Taraxacum officinale*); Canada thistle (Cirsium arvense**); com m on three-seed m ercury (Acalypha rhomboidea). The grasslands offer an awesome opportunity to shape large acreage at Oak Spring. This is more fully explored in Part 3.
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Oak Spring Trees Trees speak to a site’s history, ecology, and culture. Oak Spring contains trees of all ages, sizes, and importance. They show how peoples’ values have changed over time. As Oak Spring begins its next phase of stewardship, we take stock of what occurs today. This is a summary of ages and significance of Oak Spring’s 638 open-grown trees, with notes on the property’s most significant trees. OLD GROWTH FOREST As noted in the inventory, the forested slope along Goose Creek contains old growth trees (here defined as trees over 200 years) based on external characteristics similar to those described by Pederson (2011). The following trees were cored and interpolated to approximate their ages: AGES OF OLD GROWTH TREES in the forest. Species
Diameter (in)
Core (in)
Count
White oak
32.5
14.0
207
245 (1770)
White oak
30.0
13.5
240
290 (1725)**
Post oak
21.0
8.75
264
320 (1695)**
Black gum
14.0
7.25
185
200 (1815)
Int. age*
* Interpolated age is made by adding years (based on the rings/inch of the lowest 2 inches) for the length of the missing core, and the height gap between the core location and the ground. **These oaks show extremely slow growing conditions in their early years (early 1700s) indicating closed canopy forest at that time.
Additional old growth white oaks, black walnut, black gum, and hickory occur in this forest. Some white oaks may reach 300 years. The forest also contains several dead eastern red cedar trees. The species enters a site after disturbance and requires partial or full sun to grow. It typically invades old pastures, but rarely succeeds in closed canopy forest. One tree was cored: Species
Diameter (in)
Core (in)
Count
Int. age
Red Cedar
14
6.5
112
140+ (1875+)*
*Tree is dead and decomposition is slow in cedar. Tree germinated before 1875, possibly as far back as 1850 (dead for 25 years).
The tree tells us the old growth forest slope had openings on the upper edge in the middle 1800s. With no fire scars on any trees in the forest, we look to woodland grazing as the disturbance during that century. The stone fence on the north boundary also suggests this. Based on tree rings of oaks mentioned above, we also know the site was closed canopy forest in the early 1700s (presettlement). The lack of stumps suggests no timber cutting in at least 75 years. OPEN GROUNDS TREES All 638 open ground trees were inventoried to species (when possible), GPS marked, and diameters measured (in inches). To be counted, a tree had to be mowed underneath. This excluded all “wild” trees found in the forests and woodlands
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and also all ornamental trees that occur by buildings, within the garden, etc.
details the data with the highest 5 values in each category highlighted.
Oak Springâ&#x20AC;&#x2122;s 638 open-grown trees span 57 species or genera (64 trees were not identifiable to species). Apple (Malus pumila) is the most common tree with 152 trees. These trees span at least 28 varieties. With additional fruit tree species (see Fruit Tree section below) the fruit tree total is 193 trees. Ornamental exotics total 93 trees and native (some ornamental) total 353 trees. Celtis (hackberry) is the most common non-orchard tree.
Because of the excellent care the trees received during Mellon times, many ancient trees remain. White oaks, black gums, black walnut, and others reach over 200 years. The table details the interpolated ages of several cored opengrown trees. A map follows below showing the locations of open grown trees >200-years.
AGES OF OPEN GROWN TREES from open grounds (not forest). The full-page table below outlines the numbers of trees of each species (or genera), as well as their average diameters, and total basal area for the species (or genus). Species with only one individual at Oak Spring were not included. Those include: American elm (Ulmus americana), white pine (Pinus strobus), basswood (Tilia americana), Turkish hazelnut (Corylus colurna), Catalpa sp., honey locust (Gleditsia triacanthos), Cornus sp., sweet cherry (Prunus avium), Ulmus sp., Nectarine, and Viburnum sp. Though apples make up 24% of all trees at Oak Spring, they make up only 4.3% of basal area (a measurement of the crosssectional area of a tree 4.5 feet high). The 5 species with greatest basal area (sycamore, white oak, red maple, willow oak, Salix) together make up 41% of OSG basal area. Unlike apples, large diameter individuals dominate these species. Sycamore, with only nine trees each averaging 48 inches in diameter, comprises the most basal area. The table below
Species White oak Dogwood Bl. walnut Black gum Black gum White oak
Diameter (in) 40 9.75 28.5 32.5 29.5 53
Core (in) 12 4.25 11.5 13 7 21.75
Count 132 99 147 247 ~200* 212
Int. age 225 (1790) 115 (1800) 193 (1820) 301 (1715) 410 (1625) 257 (1760)
*The rings on this blackgum were indistinct despite adding phloroglucinol to bring out the rings. The count provided here is an average of multiple counts (188-212 range). Considering this, and that I retrieved only half of the core (hollow) the tree age is estimated at 300-500 years.
The 45 native species of trees and shrubs are listed with scientific names in a table at the end of this section.
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SUMMARY OF OPEN GROWN TREE IMPORTANCE AT OAK SPRING. Species with only one tree were not included here (n=10); see text. DBH refers to Diameter at Breast Height in inches. Basal area refers to the total cross-sectional surface area in feet2 for all trees of a species. Green highlight indicates highest value. Yellow highlight shows remaining in top-five. Carya includes C. tomentosa and C. glabra only. Number Average Basal Area Number Average Basal Area Species Species of trees DBH in. total in ft 2 of trees DBH in. total in ft 2 Acer rubrum
25
27.34
117.94
Morus sp.
5
28.40
27.95
Acer saccharum,
8
22.50
22.67
Nyssa sylvatica
4
29.75
19.43
Amelanchier sp.
4
10.50
2.78
Paulownia sp.
2
24.50
7.53
Carya cordiformis
13
22.69
41.16
Platanus occidentalis
9
47.78
133.20
Carya sp.
30
8.47
15.48
Prunus persica
14
2.36
0.64
Celtis occidentalis
43
16.70
83.52
Prunus serotina
7
20.71
19.13
Citrus trifoliata
34
6.26
7.74
Prunus sp. (fruit cherry)
7
6.33
1.57
Cornus florida
7
6.57
2.24
Prunus sp. (plum)
5
2.80
0.25
Crateagus sp.
15
10.47
9.94
Pyrus sp. (pear)
4
6.75
1.24
Diospyros virginiana
5
10.80
3.71
Quercus alba
16
35.56
130.41
Euonymus alatus
2
2.00
0.04
Quercus coccinea
2
15.00
2.47
Fagus grandifolia
9
23.89
31.02
Quercus palustris
15
25.13
59.84
14
30.33
50.09
Quercus phellos
12
39.00
117.33
Ginkgo biloba
2
12.00
1.57
Quercus rubra
5
36.00
41.50
Gymnocladus dioicus
2
27.00
8.00
Quercus sp. (Lobatae)
12
22.25
34.59
Ilex sp.
14
12.79
15.59
Quercus velutina
6
28.83
29.36
Juglans nigra
29
22.90
90.45
Robinia pseudoacacia
20
21.25
62.53
Juniperus viginiana
4
4.25
0.40
Rosaceae (unknown fruit)
10
6.30
2.81
Liquidambar styraciflua
3
38.33
24.14
9
43.44
104.44
Liriodendron tulipifera
3
16.33
8.21
Sassafras albidum
15
13.00
1.94
Magnolia sp.
3
12.00
2.53
Styphnolobium japonicum
4
21.00
9.70
Malus pumila (Apple)
152
6.43
63.03
Tilia sp.
4
23.75
12.80
Malus sp. (Crabapple)
12
10.00
8.50
Unknown
7
2.86
0.40
Fraxinus sp.
Salix sp.
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FRUIT TREES With 193 trees growing at Oak Spring (not counting crabapple or Citrus), fruit trees make up a significant portion of the landscape. Apples, with 152 trees, make up 79% of fruit trees (and 24% of all trees), but peach (14 trees), cherry (7), plum (5), pear (4), nectarine (1), and unknown fruit tree (10) also occur. The trees receive regular pruning, disease treatment, and many apples are harvested and donated.
Apple Peach Unknown fruit Cherry Plum
Red Delicious, Golden Delicious, Black Twig, Lady, Grimes Golden, White Transparent, Jonafree, Red Rome, Pink lady, Snow, Gold rush, Macintosh, Johnathan, Wealthy, Sops a Wine, York, Fuji, Gala, Yellow Delicious, Red Fuji, Stayman Winesap, Red Gravenstein, Amere de Berthcourt, Red Winesap, Cox’s Orange Pippin, Honeycrisp, Davenport Russet, Arkansas Black, Albermarle Pipen, and Spitzenburg. It is recommended that a separate management plan for fruit trees be completed to address the following management concerns: • • • •
Inventory of varieties and labeling on trees Disease and pest threats and treatment plan Pruning style and frequency Schedule and time frame for harvest
Pear Nectarine
Fewer than half of OSG tree varieties are labeled. Several varieties are considered historic, heirloom, or are of international (English) provenance. Apple varieties at OSG include at least these 28 varieties:
Considering the dominance of apples, it is also worth considering diversifying the crop to include higher proportions of other fruit trees, especially peaches. As shown by the 1937 aerial photo, Oak Spring has a long tradition of orchard production. Mrs. Mellon had a great affinity for apple trees and fine stewardship is apparent today.
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OSG SIGNIFICANT TREES In addition to the old growth trees found in the forest, a number of other significant trees occur at Oak Spring. Some of these are described with more detail in the Special Places section. Numbers refer to locations on the following map: 1. Oak Spring’s oldest tree This black gum is located on a small knoll by the cemetery. The core is described above and it is estimated at 400 years. See the Special Places section for a photo of the tree. 2. Black gum at Vogel’s driveway This black gum occurs close to the house formerly occupied by Mr. Lloyd. The tree is estimated to be 301 years. 3. Black gum on Loughborogh Lane The tree occurs by the large bedrock outcrops by the glasshouse. The tree was not cored, but based on bark is estimated to be of similar age (300+) to other black gums. 4. Mrs. Mellon’s willow oaks South of the residence are two large willow oaks. Despite the 55-inch diameter, the trees are young. Ronnie Caison, Oak Spring house manager, noted Mrs. Mellon said she planted the trees. This agrees with the age based on rings and imagery (early 1950s). The trees are similar in age to willow oaks planted by the president’s house.
5. Oldest Dogwood This dogwood is relatively large for the species (9.75 inches in diameter); however, the exfoliating bark suggests the tree has aged. As noted the tree is approximately 115 years old. There are no published reports on the lifespan of dogwood, nor reports on the Eastern Old List (2017). This tree should be nominated as the oldest known Cornus florida. 6. White Bench Oak This large white oak by Spring House Pond is aged to 257 years (1760). An upper branch is cored to 215 years (1801) suggesting the tree has always been open grown. The land may have been open by fire from American Indians, however, all sources suggest they left the area with the treaty of Albany in 1722. The tree may also be recording settlement by someone predating Robert Fletcher. Nonetheless, the tree reveals another piece of Oak Spring history. 7. The Largest Oak This massive white oak appears also to have always been open grown (this should be confirmed through coring). This is the largest original oak on the property and it is concealed by its topographic position. 8. Sycamore Located by the Loughborough Springs, this 65-inch diameter is of unknown age. The tree appears mid-sized on 1937 imagery, and is estimated at 150 years. It’s the largest tree at Oak Spring except for a larger Sycamore on Goose Creek.
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Vegetation References Fleming, G.P., K.D. Patterson, and K. Taverna. 2017. The Natural Communities of Virginia: a Classification of Ecological Community Groups and Community Types. Version 3.0. Virginia DCR, Division of Natural Heritage, Richmond, VA. http://www.dcr.virginia.gov/natural-heritage/natural-communities/ [Accessed: 24 December, 2017] Pederson, Neil. 2010. External characteristics of old trees in the Eastern Deciduous Forest. Natural Areas Journal 30(4): 396-407. Spria, T. 2012. Wildflowers and Plant Communities of the Southern Appalachians and Piedmont. University of North Carolina Press. Weakley, A., C. Ludwig, and J. Townsend. 2012. Flora of Virginia. Botanical Research Institute of Texas.
SIGNIFICANT TREES IN THE OPEN AREAS OF OAK SPRING. Numbered trees are described above. Trees labeled WO are white oaks generally over 200 years with some confirmed to 280 years. BW trees are similarly aged black walnut.
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LIST OF OAK SPRING’S 45 NATIVE TREE SPECIES. Status describes presence at Oak Spring (i.e. “Rare” means only a few individuals present).
Box elder Red maple
Acer nigrum Acer rubrum
Status Oak Spring Common Occasional
Sweetgum
Liquidambar styraciflua
Tulip poplar
Liriodendron tulipifera
Status Oak Spring Planted Occasional
Sugar maple
Acer saccarum
Rare
Osage orange
Maclura pomifera
Occasional
Serviceberry
Amelanchier sp.
Rare
Southern magnolia
Magnolia grandiflora
Planted
Pawpaw
Asimina triloba
Uncommon
Black gum
Nyssa sylvatica
Occasional
Musclewood
Carpinus caroliniana
Common
White pine
Pinus strobus
Rare
Bitternut hickory
Carya cordiformes
Common
American sycamore
Platanus occidentalis
Uncommon
Pignut hickory
Carya glabra
Uncommon
Black cherry
Prunus serotina
Occasional
Shagbark hickory
Carya ovata
Uncommon
White oak
Quercus alba
Abundant
Mockernut hickory
Carya tomentosa
Uncommon
Pin oak
Quercus palustris
Planted
Catalpa
Catalpa sp.
Rare
Willow oak
Quercus phellos
Planted
Hackberry
Celtis occidentalis
Common
Northern red oak
Quercus rubra
Common
Eastern redbud
Cercis candensis
Rare
Quercus stellata
Rare
Flowering dogwood
Cornus florida
Rare
Post oak Water oak
Quercus nigra
Planted
Hawthorn
Cretagus sp.
Uncommon
Black oak
Quercus velutina
Uncommon
Persimmon
Diospyros virginiana
Occasional
Black locust
Robinia psudoacacia
Occasional
American beech
Fagus grandifolia
Rare
Black willow
Salix nigra
Rare
White ash
Fraxinus americana
Common (dying)
Sassafrass
Sassafras albidum
Uncommon
Honeylocust
Gleditsia triacanthos
Uncommon
American basswood
Tilia americana
Rare
Witch hazel
Hamamelis virginiana
Rare
American elm
Ulmus americana
Rare
American holly
Ilex opaca
Uncommon
Slippery elm
Ulmus rubra
Occasional
Black walnut
Juglans nigra
Common
Blackhaw virburnum
Viburnum prunifolium
Uncommon
Juniperus virginiana
Rare
Common Name
Eastern red cedar
Species Name
Common Name
Species Name
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E XOTIC P LANTS Description Exotic plants are those that are not native to a region. They’ve been brought in as ornamental or culinary plants, or hitched here inadvertently. Invasive plants are those that spread and take over a site rapidly. Exotic invasive plants suppress native vegetation, reduce diversity, and change soil chemistry. Like a cancer of the land, they spread unchecked by ecological feedbacks. Exotic invasive plants are widely recognized as being the greatest threat to forests and biodiversity after habitat fragmentation and land use change. Because they reproduce annually, the cost to eradicate exotic plants increases exponentially. One of greatest environmental investments that can be made at Oak Spring is the elimination of exotic invasive plants. The following maps and tables document exotic invasive plants found at Oak Spring and their relative abundance. This is a list of observed species in 2016 and 2017 in the forest, woodland, and other wild areas. Plants in the mowed meadows were not assessed. Several woody species such as tree of heaven and multiflora rose are particularly egregious. This was not a quantitative study; it was a subjective observational assessment taken during a multi-parameter inventory of Oak Spring. New species will pop up, and existing ones will spread and increase.
All the forested and unmowed areas at Oak Spring have considerable exotic pressure. There are two reasons for this. First, the land has over 200 years of agricultural disturbance history. The Young Woods was formerly open pasture, the forest was grazed woodland, and the runs below the ponds were clear open. As these have grown up, opportunistic exotic seeds have settled in. The second factor is the problem of edge. Nowhere are Oak Spring’s forests greater than 100 meters deep and most are much narrower than this. This exposes considerable edge, which sunlight penetrates and facilitates the growth of exotics. Expanding the core forest area and reducing edge can reduce exotic pressure. But this will take decades or a century. Because of the related issues of limited core forest and excessive edge, as well as recent disturbance history, Oak Spring’s natural areas are subject to high exotic pressure. The species listed below are limited to the forest areas and successional sites. Tables include woody exotics (trees, shrubs, and vines) and herbaceous exotics. Exotics in the open meadows are not included because it is expected that the fescue-dominated meadows will be converted to native warm season grasses and herbs. (That, and I’m largely unfamiliar with native or exotic meadow plants.) Plants are described in terms of Relative Abundance, that is, how commonly the species is found at Oak Spring.
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Dominant woodland invasive plant species at Oak Spring. Their occurrence is listed specific to Oak Spring. Common Name Norway maple (Tree) Tree of heaven (Tree) Japanese barberry (Shrub) Oriental bittersweet (Vine) Trifoliate orange (Tree) Autumn olive (Shrub) Burning bush (Shrub) English ivy (Vine) Japanese honeysuckle (Vine) Shrub honeysuckle (Shrub) Princess tree (Tree)
Species
Occurrence in Oak Spring
Acer platanoides
Rare. A few trees found in the old forest. Low threat.
Ailanthus altisima
Occasional. 2 stands occur in the forest. 2 other stands have been eliminated. The species can colonize large areas and can be difficult to eliminate. Serious threat.
Berberis thunbergii
Rare. Species is nowhere abundant; occurs as isolated individuals in wooded areas.
Celastrus orbiculatus
Occasional along forest edges. The species poses a significant threat and can be difficult to remove when established. Serious threat.
Citrus trifoliata
Rare. Isolated individuals in the Young Woods. Source is Oak Spring.
Elaeagnus umbellata
Rare. Found along edges of meadows. Moderate threat.
Euonymus alatus
Occasional. Many young plants in the Woodland Garden area. Source likely OS.
Hedera helix Lonicera japonica
Uncommon. The species occurs in the old woods growing on a contained stand of oaks near Goose Creek. Phase 1 treatment completed in 2017. Abundant. Vies with multiflora rose as most abundant exotic. It occurs mainly along edges of the forest and as a ground creeper in the forest.
Lonicera spp.
Uncommon. Only a few populations along Wild Pond margin, and outlet drainages.
Paulownia tomentosa
Rare. Species occurs as planted ornamentals near the cemetery. Wood is valuable.
Sweet cherry (Tree)
Prunus avium
Rare. Scattered trees in the forest. Several were girdled in 2017.
Multiflora rose (Shrub)
Rosa multiflora
Abundant. Oak Springâ&#x20AC;&#x2122;s most abundant woody exotic. Dense patches in the forest. Additional stands around Wild Pond and its outflow all the way to Goose Creek
Wineberry (Shrub)
Rubus phoenicolasius.
Common. Mainly around forest edges and in young and old forest. Scattered individuals and occasional thickets.
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TABLE CONTINUED: Common Name Garlic mustard (Herbaceous biennial) Mile-a-minute (Annual vine) Gill-over-the-ground / Creeping Charlie (Perennial Creeper) Common chickweed (Annual Herb) Japanese siltgrass (Annual Herbaceous)
Species
Occurrence in Oak Spring
Alliaria petiolata
Common. Small patches seen in the forest. The species has the ability to colonize high quality forests. Serious threat.
Persicaria perfoliata
Occasional. Occurs as isolated individuals in the wooded areas and edges
Glechoma hederacea
Abundant. Plant is abundant in the old forest as a ground creeper/cover.
Stellaria media
Abundant. Found along ground of old woods. Winter treatment.
Microstegium vimineum
Abundant. The species occurs in dense patches in the old forest and forms nearly continuous cover in the young forest. Main herbaceous issue at Oak Spring.
Management Goals and Strategy Oak Spring’s exotic plant goal should be 90% elimination in 5 years. The established seed bank will continue to sprout for several years, and birds, other animals and the wind will bring in new seed. But with a concerted effort, all the woody species can be eradicated in 2 to 3 years, and most herbaceous species within 5 years. APPROACH: TOP-DOWN Invasive management is best done with a top-down strategy: first trees, shrubs, and then herbaceous and finally the pernicious creepers. It’s difficult and perhaps inefficient and
ineffective to treat, for example, stilt grass in and among patches of multiflora rose. Instead, reduce rose thickets first, and focus on the herbaceous plants after the woody plants are brought under control. In some areas lacking woody exotics, it may be possible to work on patches of herbaceous plants in conjunction, but considering the degree of infestation in most of Oak Spring’s forest, it’s probably best to work all of the stilt grass in one year, rather than piecemeal because seeds from adjacent areas will drift into eradicated areas.
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W O OD Y EXOTIC PLA N TS INF ESTA TIO N AT O A K S PRIN G . Largely clear of exotics; discrete localized individuals. Low-level infestation: Scattered individuals, isolated patches of a single species. Moderate: Multiple species, patches, or uniformly scattered and reproducing. Heavy infestation: Multiple dense patches, impenetrable tickets, multiple species.
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NEIGHBORS Without a glass bubble over Oak Spring, seed will drift in from adjacent properties. Oak Spring can counter this by discussing invasive management with neighbors. They may be unaware of the situation and be willing to address theirs. Or the neighbors may be willing to allow Oak Spring to continue the work in their private property. Going forward, Oak Spring will need to monitor the property buffers and determine if seed drift and subsequent costs are worth the potential investment in eradicating the neighborâ&#x20AC;&#x2122;s property. For better or worse, the adjacent forest to the north of Oak Spring (along Goose Creek) adds only about 10 acres. CONTRACTORS Professional contractors can often work more efficiently and more cost effectively than in-house workers. The Virginia Department of Forestry has provided Oak Spring a list of contractors that do invasive plant removal. TEMPORARY LABORERS For simple, labor intensive work, Oak Spring should consider using day laborers from an agency. Garlic mustard, for example, is best treated by pulling. It is labor intensive but effective. Most organizations rely on volunteers for garlic mustard pulling, with mixed results. With a crew of day laborers garlic mustard could be eliminated as a phase one project in late April/early May.
EXPERIMENTATION There are proven approaches for eradicating exotic invasive plants. A summary of commonly accepted strategies for each species is summarized in the table below. In general the most common applications for small acreages like Oak Spring are the use of herbicides (backpack sprayers) and hand tools. Eradication using these strategies is effective but requires persistence. There is less agreement about the best strategies for treating mixed species infestations especially when they are mixed with valuable native flora. In 2017 Oak Spring performed a number of test strategies to see what works best in mixed species exotic infestations. Plots were mowed and sprayed, hand pulled, and sprayed-only in an effort to find the most efficient and effective strategy. In general, the use of heavy machinery in exotic plant eradication is limited to conducive topography and large infestations. When woody plants are mowed down, they typically resprout. Herbicide application is important. The use of machinery in forest settings presents the possibility of damage to native flora (and fauna), soil compaction, root damage, and disturbed soil becomes open to additional infestation. The Oak Spring forest contains steep slopes and trees over 300 years old which will be damaged with the use of heavy machinery.
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PROPOSED ERADICATION PLAN for Exotic Plants at Oak Spring Phase Phase 1
Timing Fall 2017
Winter 2017-18
Treatment of woody exotics in forest area including Multiflora rose, Ailanthus, English ivy, and other less common woody exotics. (Japanese honeysuckle not treated). Treat woody exotics in pond edges and drainages working from top of watershed down to Goose Creek. Japanese honeysuckle treated in forest and edges.
Summer/fall 2017
Fences and walls treated.
April/May 2018
Garlic mustard pulled from forest area.
Summer/Fall 2018
Year 2 follow up on woody exotics.
Summer 2018
Begin large-scale effort on Japanese stiltgrass.
Winter 2018
Year 2 follow-up on Japanese honeysuckle.
Summer 2018
Year 2 treatment on fences and walls.
Spring 2019
Round 2 garlic mustard pulled from forest area.
Summer/Fall 2019
3rd follow up on woody plants.
Summer 2019
Stiltgrass treatment year 2. Adapt based on best test plot results.
Fall 2019
Take stock. Determine which herbaceous priority is next based on vegetation response.
Spring 2020
Begin planting native shrubs and herbaceous if herbicide use will be limited in those areas.
All year: 2020
Follow up treatment for all previous work.
All year: 2020
Determine needs and adapt.
2021
Continue planting native species.
2021
Continue follow up to herbaceous plants and working with neighbors.
2021
Woody plants should be eliminated at this point. Stiltgrass and garlic mustard mostly.
Fall/winter 2017
Phase 2
Phase 3
Phase 4
Phase 5
Treatment Task
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BEST MANAGEMENT PRACTICES for Oak Springâ&#x20AC;&#x2122;s common exotic plant species Common Name
Season
Approach
Norway maple (Tree)
Growing season for ID
Hand pull seedlings; girdle trees; glyphosate on cut stump or leaves if needed.
Tree of heaven (Tree)
Summer
Diligence. Repeat cutting in open areas. Hack and squirt in forests using Garlon 3A.
Spring/Summer
Diligence. Hand pull during flower or seed stage; glyphosate for large infestations anytime.
Late summer during fruiting; early spring
Hand pull (wear gloves) or cut stump treatment or foliar application of glyphosate or Triclopyr.
Oriental bittersweet (Vine)
Fall/winter; anytime
Persistence! Cut stems and treat with glyphosate. Foliar treatment depends on impacts to surrounding plants.
Autumn olive (Shrub)
Late summer/fall
Hand pull; Cut stump and treatment with glyphosate.
Burning bush (Shrub)
Summer/fall
Hand pull; Cut stump application of glyphosate.
Winter creeper (Vine)
Year round, above 40F
Cut stem and treat with glyphosate or Triclopyr, or foliar treatment.
English ivy (Vine)
Warm winter days
Hand-pull young plants. Cut stem and treat with glyphosate. Foliar treatment for ground cover.
Chinese privet (Shrub)
Late fall
Cut stump application of glyphosate.
Japanese honeysuckle (Vine)
Late fall/Winter
Persistence and commitment. Hand pull if possible. Do foliar treatment with glyphosate after other plants go dormant.
Shrub honeysuckle (Shrub)
Summer/fall
Hand pull. Stubborn plants get cut stump treatment with glyphosate.
Garlic mustard (Herbaceous) Japanese barberry (Shrub)
Summer/fall
Hand-pull mid-late summer. Weed whack late summer before seeding. Foliar glyphosate spray with care. Girdling larger trees; cut stump treatment for smaller trees with glyphosate or triclopyr.
Sweet cherry (Tree)
Summer/fall
Not much information available. Girdle large trees, cut stump treatment on smaller trees.
Multiflora rose (Shrub)
Summer/fall
Difficult. Multipronged approach needed. Cut stem for larger plants, glyphosate cut stems or foliar. Persistence will be needed.
Trifoliate orange (tree)
Summer/fall
Cut stump treatment with glyphosate; hand pull or foliar treatment of seedlings.
Japanese siltgrass (Herbaceous) Princess tree (Tree)
Summer
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Virginia bluebells (Mertensia virginica)
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O AK S PRING F AUNA In ecology, plant communities reflect variability in substrate conditions (geology, soil, moisture, topography, slope, etc.) and disturbance (frequency, intensity, etc.). Wildlife occurrence is a reflection of an animal’s habitat occurrence. As described in the vegetation section, Oak Spring contains a number of plant community types (differentiated largely by human land use) and it is expected that an array of critters from insects and other invertebrates, to aquatic vertebrates, a seasonal variety of birds, and mammals big and small, inhabit the forest and fields. Oak Spring’s 262 acres, however, contain fragmented patches of woods and a large swaths of fescue-dominated fields. These fields have their own unique ecology, but in general they lack the structure, complexity, and diversity to make them useful to many native animals. A goal of this document is to lay a foundation for improving plant community composition and structure such that wildlife can follow.
This section describes Oak Spring’s fauna, wildlife hotspots, and a host of strategies for drawing watchable wildlife to the ponds, woods, and meadows. Features can be added to foster healthy, diverse animal communities. These strategies, as well as those for reducing overabundant nuisance wildlife, are also considered. While Oak Spring is a plant-centric organization, healthy, diverse wildlife will create captivating experiences for guests, and contribute to a healthy ecosystem for all organisms.
Description Oak Spring contains a 262-acre sweep of Virginia Piedmont. The grasslands, woods, ponds, and ancient trees offer opportunity to wildlife. In a short time I’ve observed dragonflies and damselflies, freshwater mussels, butterflies, and a variety of birds over several seasons. While a complete fauna inventory was beyond the scope of this project, a number of cursory observations and documentation offer a snapshot of Oak Spring’s fauna.
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Oak Spring’s vertebrate fauna documented in 2017 include: Am phibians Grey tree frog Fowler’s toad Leopard frog Green frog Spring peeper Fish Channel catfish Bluegill Yellow perch Large mouth bass Reptiles Northern water snake Snapping turtle Painted turtle Garter snake Eastern fence lizard Birds
M am mals Red fox Coyote Eastern grey squirrel Eastern fox squirrel White-tailed Deer Eastern cottontail Woodchuck Eastern chipmunk Beaver (sign) Northern raccoon Virginia opossum American black bear Other Taxa In addition to these vertebrates, Oak Spring contains an unknown number of insects and other invertebrates. Virginia Working Landscapes identified 7 species of bumblebee (out of 10 regionally present). See appendix for VWL’s full report.
See list on following page.
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LIST OF 92 BIRD SPECIES observed at Oak Spring in February, April, June, and November 2017 as well as intermittently from May to August by Virginia Working Landscapes. Observers include: Doug Stotz (Nov.), Mark Aronson (Feb.), David and Nancy Hines (April), Jennifer Randall (May), Michael Gaige (all seasons) and Virginia Working Lands May to August. American Black Duck Mallard Canada Goose Wood Duck Bufflehead Trumpeter Swan American Turkey Ring Necked Pheasant Great Blue Heron Black Vulture Turkey Vulture Osprey Bald Eagle Northern Harrier Red-Tailed Hawk Killdeer American Woodcock Spotted Sandpiper Mourning Dove Yellow Billed Cuckoo Great Horned Owl Short-eared Owl Chimney Swift
Ruby Throated Hummingbird Belted Kingfisher Red Headed Woodpecker Yellow-bellied Sapsucker Pileated Woodpecker Northern Flicker Downy Woodpecker Hairy Woodpecker Red Bellied Woodpecker American Kestrel Great Crested Flycatcher Eastern Wood Peewee Eastern Phoebe Acadian Flycatcher Eastern Kingbird Red Eyed Vireo American Crow Fish Crow Common Raven Blue Jay Barn Swallow Purple Martin Tree Swallow
Carolina Chickadee Tufted Titmouse White Breasted Nuthatch Brown Creeper House Wren Carolina Wren Ruby Crowned Kinglet Golden-crowned Kinglet Wood Thrush Eastern Bluebird American Robin Northern Mockingbird Grey Catbird Brown Thrasher European Starling Cedar Waxwing House Sparrow American Pipit House Finch American Goldfinch Common Yellowthroat Yellow-breasted Chat Yellow-rumped Warbler
Palm Warbler Swamp Sparrow White-throated Sparrow Song Sparrow Savannah Sparrow Eastern Towhee Field Sparrow Grasshopper Sparrow American Tree Sparrow Chipping Sparrow Dark Eyed Junco Indigo Bunting Scarlet Tanager Northern Cardinal Bobolink Red Winged Blackbird Rusty Blackbird Eastern Meadowlark Great Tailed Grackle Common Grackle Brown Headed Cowbird Baltimore Oriole Orchard Oriole
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Oak Spring Wildlife Hotspots A number of areas at Oak Spring contain the complex structure and diversity attractive to wildlife. Observation in 2017 suggests these listed below areas seem especially rich for wildlife and contain otherwise uncommon features. A goal for landscape management at Oak Spring is to foster and enhance this type of structure and diversity. These wildlife hotspots at Oak Spring include: • • • • • • •
Goose Creek: aquatic hotspot Goose Creek Bottomlands: a wildlife corridor Ponds: a draw for terrestrial and aquatic organisms Rock M eadow: structure for raptors and mid-sized mammals Scattered Trees: widely documented as adding diversity to faunal communities Forest: locally rare landscape element Scrub-shrub Thickets: structural element in the open landscape
WILDLIFE HOTSPOTS AT OAK SPRING. Includes ponds, bottomland, forest, and Rock Meadow. Smaller features such as scattered trees and thickets are not shown due to scale.
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Attracting Watchable Wildlife Attracting wildlife at Oak Spring is about managing habitat. In a simplified landscape (low-diversity grasslands) creating habitat means adding diversity and structure. Diversity will come from warm season grass and meadow installations, reforestation, and pond margin planting. Species richness and abundance will increase with these actions. Structure means adding complexity to the landscape in the form of scattered trees, shrub thickets, pond features, and artificial boxes, platforms, and perches. The addition of structure is geared toward providing cover and opportunity for animals small and large. Adding boulders and logs to ponds, perches and platforms for raptors, and boxes for small birds, will attract watchable wildlife and create a more robust community. The list below summarizes strategies for wildlife enhancement with generalized locations at Oak Spring. BOXES Nest cavities are a limiting factor in determining presence or absence of some species. Right Bird, Right Box, published by the Cornell Lab of Ornithology (2017) lists appropriate boxes and species in decline that benefit from nest boxes. These include: American kestrel, tree swallow, barn swallow, barn owl, screech owl, eastern phoebe, among many others. Bat boxes should also be installed in proper locations near water. This is an inexpensive way to increase wildlife at Oak Spring. Some boxes will need to be cleaned annually.
NEST PLATFORMS Osprey have been observed at Oak Spring and the species readily takes to artificial nest platforms. Other raptors may also use them. The Cornell Lab of Ornithology details appropriate construction and location for nest platforms (Cornell Lab, 2017a). Two potential locations for nest platforms include the Goose Creek bottomland in the far southwest corner of Oak Spring, and at the northwest corner of the Lower Pond (near its inlet). RAPTOR POLES/PERCHES Until scattered trees are planted and mature, perches can be installed to allow raptors and other birds, such as flycatchers, places to hunt from. Two perches in the Rock Meadow, and a couple in other locations will provide the perch locations predator species need. ROCKS, LOGS, AND FLOATING MATS Wild Pond has several boulders near its inlet that often have basking turtles and waterfowl on them. Structure like this is important for aquatic animals as they can exit the water without having to leave the safety and security of the pond. Oak Spring can add large partially submerged boulders and logs to Spring House Pond (boulders only), Tree Shop Pond, and the Lower Pond. When a large oak is felled at Oak Spring it can be placed in a pond from the shoreline.
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FISHLESS POND(S) Fish are apex predators in small ponds. Some invertebrate species, amphibians, and reptiles are limited by the presence of fish. Oak Spring’s three smaller ponds: Spring House, Eliza’s, and Wild Pond could all have fish eliminated making them more suitable to non-fish species. With the recent pond dredging, Spring House Pond may be without fish already. Short of draining, the most common method for eliminating fish is through the use of Rotenone. Leaving the two larger ponds with fish will add to Oak Spring’s diversity and provide a food source for Osprey and other fish-eating animals. SCATTERED TREES Scattered trees in open environments have been termed “keystone structures” by ecologists for the enormous role they play in open land ecosystems. They function as habitat for a host of invertebrates, and as perching, resting, and nesting sites for birds and mammals, among other functions. The addition of one tree in a field can increase diversity 100fold. (These are covered in more detail in Part 3.) SHRUB ISLANDS In Oak Spring’s sea of grasses, islands of shrubs can become wildlife hotspots. Like scattered trees, thickets add cover and complexity for critters large and small. One shrub island of less than ¼ acre, per 5-acres is a reasonable goal. Species can include: Rubus spp., sumac, wild plum, dogwood, cedar, elderberry, Viburnum spp. buttonbush, Ilex spp., Devil’s walking stick, false indigo, wahoo, and others. A publication
by the Kentucky Dept. of Fish and Wildlife (2017) outlines planting plans for cover thickets. COARSE WOODY DEBRIS AND DEBRIS PILES In forests and woodlands, animals are often limited by the amount of woody debris from fallen logs and branches. A host of invertebrates depend on these features, as do the vertebrate species that feed on them. When large trees are cut at Oak Spring, the wood can be repurposed in the young woods, the floodplain, or emerging reforestation areas. This adds critical structure into a system that if left to its own, will not generate such features for centuries. CONIFER GROVE In winter many birds spend cold nights in dense groves of conifers (pine or cedar). Within the reforestation plan a small cluster of conifers should be planted to host the turkeys, owls, and other birds that roost in such places. This is described more fully in Part 3. BUTTERFLY GARDENS Butterflies and other pollinators thrive in places with dense concentrations of showy flowers blooming throughout the growing season. With the installation of warm season meadows, much of this will occur. Additional gardens can be designed in locations closer to Oak Spring’s residential spaces.
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Nuisance Wildlife Wildlife can reach undesirable populations. In recent decades, two species have reached unsustainable “nuisance” populations levels and Oak Spring is not immune from this. Canada geese and white-tailed deer occur at levels that damage ecological integrity and potentially Oak Spring’s conservation investments. CANADA GEESE The Canada goose has attained elevated resident populations in Virginia over the past 20 years. The species has traditionally been a migratory bird, wintering in the eastern US and breeding in the far north. Resident populations have figured out they can stay in places like Oak Spring year round and there is concern that as more birds do this they may loose their migratory behavior. Locally, the birds’ impact includes fecal concentrations on shorelines and in ponds. Shorelines can erode with heavy use. Managing geese means first modifying habitat to make the site unsuitable to geese. Geese require easy ingress and egress from pond to land, and visual barriers largely prevent permanent residence. Planting shrubs and other tall plants (~2 feet) around all pond margins should reduce geese numbers. This will be especially important on Spring House Pond where grass is kept short. Around the large ponds management can allow the grass to grow tall.
Additional remedies include hired dogs and noisemakers. Habitat modification should be tried first. Canada geese nests found at Oak Spring can be addled (coating with corn oil) to prevent eggs from developing. This will reduce the populations of new birds in Oak Spring’s ponds. (A simple federal permit, available online, is required.) WHITE-TAILED DEER The overabundance of white-tailed deer in much of the eastern United States is one of the most vexing, pernicious, and complex socio-ecological issues. The problem is recent; recall that deer were nearly extirpated from Virginia by 1930. Beginning in 1926 and until 1951 Virginia reintroduced deer from surrounding states into various counties mainly in western Virginia. In 1938 Fauquier County had no deer and by 1950 deer in Fauquier was limited only the forested Blue Ridge. By 1970 deer populations in Fauquier County were considered appropriate and by 1988 deer were considered overabundant in upper Fauquier County, as their status remains today. In 50 years deer have repopulated the county and now overshot the land’s carrying capacity. Virginia DGIF has targeted Fauquier County for population reduction (Virginia Department of Game and Inland Fisheries, 2017). The impacts caused by overabundant deer are numerous and well publicized. They include increased tick numbers and tick-born diseases, damage to agriculture and gardens, vehicle collisions (Fauquier County has over 250 annually), and more.
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The primary concern of overabundant deer at Oak Spring is poor plant regeneration and damage to conservation investments such as tree planting and exotic plant elimination. Considering the overabundant population, damage has already been done; any plant/tree susceptible to deer browse has been degraded. Plants growing today at deer level are inherently resistant to browse. Many of these are exotic.
the pressure deer are having on vegetation. Once exotic species are removed, exclosures of 10 meters square should be installed in the forest, the young woods, and in a meadow. Long-term, Oak Spring should consider a limited hunting presence and perhaps also consider off-season agricultural pest permits to keep a hunting presence year-round.
Managing deer includes the following options: • • • • •
Regulated hunting Fencing and repellents Sharpshooters Predators Do nothing
In general, a wildlife species cannot be managed in isolation. Without regional action to increase hunting pressure, predator effectiveness, or reproduction rates, deer will continue to be a problem at Oak Spring. Nonetheless, Oak Spring should consider using all of the above approaches. A limited hunt might keep a portion of deer away. Fencing will be needed in the most sensitive areas or on individual plants. Allowing the coyote population to thrive will also help. Advocacy and education with neighbors could expand management actions beyond Oak Spring. In the short term, however, Oak Spring should immediately establish experimental deer exclosures in order to understand
References Grymes, C. 2017. Deer in Virginia. George Mason University. http://www.virginiaplaces.org/natural/deer.html Cornell Lab of Ornithology. 2017. Right Bird, Right Box. https://nestwatch.org/learn/all-about-birdhouses/ Cornell Lab of Ornithology. 2017a. Platform for Success. https://nestwatch.org/connect/news/platform-for-success/ Kentucky Division of Fish and Wildlife. 2017. Cover Thickets. https://fw.ky.gov/Wildlife/Documents/coverthickets[1].pdf Virginia Department of Game and Inland Fisheries, 2017. Virginia Deer Management Plan, 2015-2014. https://www.dgif.virginia.gov/wildlife/deer/management-plan/ Wolter, F. S. Capel, D. Pashley, S. Heath. 2008. Managing Land in the Piedmont of Virginia for the Benefit of Birds and other Wildlife. American Bird Conservancy/ Piedmont Environmental Council/ Virginia Department of Game & Inland Fisheries. https://abcbirds.org/wpcontent/uploads/2015/05/PiedmontEnviroCouncil.pdf
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EBONY JEWELWING (Calopteryx maculate) along Goose Creek.
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I NDIGENOUS A RTIFACTS : T HE B OYD P AULEY C OLLECTION The northern Virginia piedmont was a rich cultural area in prehistoric times. A summary of that history occurs in Part 1. In essence, the Upperville/Fauquier Piedmont region was used heavily in Archaic times, and much less so in recent Woodland times as groups settled instead along major rivers. Oak Spring, and the former Mellon estate more broadly, has a tangible record reaching back over 10,000 years. Boyd Pauley was a gardener at Oak Spring and Rokeby farms for over 40 years (retiring 2017). During that time he (and his family members) amassed a collection of Native American artifacts recovered from throughout the Mellon properties. The collection includes nearly 70 projectile points, two ax heads, and a few unidentifiable objects. An unattributed report written by an archeological professional at an unknown time (1980s or1990s?) provided interpretation of the Pauley collection. The author divides the collection into four sections, however, it is unclear which artifacts in today’s larger collection belong to which sections. It states the recovery of artifacts by Pauley “were made at Oak Spring, Edge Cliff and associated properties, as well as neighboring Glen More.” The report’s main conclusions are summarized following the images.
A BREWERTON SIDE-NOTCHED PROJECTILE POINT made of grey chert. This point was found in the excavation zone on the east side of the Tree Shop Pond by OSGF gardener Wendy Sirat in April 2017. According to archeologist Dr. Carole Nash, the point is 4,900-3,700 years old and has been heavily resharpened.
In 2017 Oak Spring had the Pauley Collection interpreted anew by James Madison University professor and archeologist Dr. Carole Nash. Oak Spring photographed each of the 78 artifacts (samples below) and Dr. Nash interpreted each to rock type, cultural period, tool type, etc. Some pieces were not identifiable. Below is a sample of several artifacts photographed by Oak Spring with interpretation by Dr. Nash. The digital collection occurs in an appendix at Oak Spring.
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Late Archaic/Early Woodland stemmed projectile point, Bare Island type. Material could be metarhyolite (from Harpers Ferry Catoctin Mountain area) or Greenstone breccia from Central Blue Ridge. 4,500-3,600 YBP. Heavily reworked.
Coarse brown jasper biface (worked both faces). As base appears to be broken, it may be a blank for making a projectile point, or it may be a damaged point, reworked for use as a knife. Possible late PaleoIndian /Early Archaic. Likely Blue Ridge Overthrust Fault Jasper (west side of Blue Ridge).
Metarhyolite Late Archaic/Early Woodland
Milky Quartz Middle Archaic period Halifax SideNotched projectile point, ca. 5,200-4,500 YBP. Probably made from local material. Resharpened.
Late PaleoIndian Hardaway-Dalton projectile point, 10,800-10,300 YBP. This is the oldest object in the collection. Probably made from local quartz. Heavily resharpened, possibly while on haft.
Madison projectile point (true arrowhead), Late Woodland, 800-400 YBP. Made from local quartz. Distal resharpened and used as graver or punch.
stemmed projectile point, Bare Island-type, similar to artifact #4. This material is found from Harpers Ferry north into Catoctin Mountain. 4,500-3,600 YBP.
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Grey chert Hardaway side-notched projectile point, 10,0009,400 YBP. Late Paleo-Indian/Early Archaic. Material is not local chert (Shenandoah Valley). The serrations represent resharpening on the haft. The distal and basal breaks may represent recent plow damage, but the basal break may have been caused by a fracture plane in the rock.
O f th e p o in t s th a t y o u h a v e , th r e e a r e fr o m th e la te P a le o In d ia n p e r io d , w h ic h r e p r e s e n t s s o m e o f th e e a r lie s t Na tiv e p e o p le in t h e r e g io n .
Catoctin metabasalt full-grooved axe. Commonly found on sites in the northern Va. Piedmont; from Middle Archaic-Late Archaic periods. Made by grinding.
Difficult to confidently identify material; could be fine-grained brown jasper or chalcedony, both of which are not local to the northern Va. Piedmont. Yadkin projectile point (true arrow-head), Late Woodland, 1,200-900 YBP.
â&#x20AC;&#x201C; Dr. Carole Nash
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Raw Material Relative Frequency Quartz Quartzite Chert Metarhyolite Jasper Unknown
FREQUENCY OF MATERIAL for Oak Spring Lithics as interpreted by Dr. Carole Nash. Of the 78 artifacts, 78% are local quartz. Others come from as far away as Shenandoah Valley, Harperâ&#x20AC;&#x2122;s Ferry, and perhaps farther.
20 18 16 14 12 10 8 6 4 2 0
Cultural Period Frequency
AGE DISTRIBUTION OF IDENTIFIABLE LITHICS in the Pauley Collection (n=54) to cultural period as interpreted by Dr. Carole Nash. Periods date to Years Before Present (YBP) and Common Era (CE): Late Paleo-Indian: 12,000-10,000 YBP; Early Archaic: 10,000-8,000 YBP; Middle Archaic: 8,000-4,500 YBP; Late Archaic: 4,500-3,200 YBP; Early Woodland: 3,200-2,500 YBP; Middle Woodland: 2,500 YBP to 900 CE; Late Woodland: 900-1,600 CE.
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Dr. Nashâ&#x20AC;&#x2122;s Interpretation
Summary of Unattributed Report
As a whole, this is a fairly typical grouping of objects from the northern Virginia. piedmont. The high percentage of artifacts manufactured from quartz indicates a local source in the general vicinity. That all of the points have been broken and/or resharpened is also indicative of re-tooling: discarding the old points in the locations where new ones are being made. I would expect that for every artifact that was picked up, there are hundreds of flakes (debris from tool making) in the same locations.
The following excerpts are taken from the report. The collection in this report was smaller than the 78 lithics now held thus these conclusions are not directly comparable to those made by Dr. Nash.
It is not unusual to have a large number of objects that can't be identified by cultural period, and this is definitely the case here. 21 of the 76 objects can only be identified as 'bifaces' they were either 'blanks' that could have been made into projectile points, or they were points that are so altered through use that the type can't be identified. Of the points that you do have, there is a very interesting tidbit: three are from the late PaleoIndian period, which represents some of the earliest Native people in the region. These are HardawayDalton and Hardaway Side-Notched varieties. You'll see from the [graph] that the cultural period most represented is the Middle Archaic, closely followed by the Late Archaic. This is also expected for your area; away from large bodies of water, we don't see the larger Late Woodland village sites, but rather, a landscape of hunter-gatherers who moved across the region throughout prehistory.
The collection suggests the presence of several sites as well as random finds documenting occupation of the area from 7,500 BC to 1,600 AD. Scattered points dating to Early Archaic and Middle Archaic periods suggest that these areas were rarely visited during early periods of Indian Prehistory. However, during the Late Archaic Period, the uplands were extensively utilized. The presence of stone axes suggests the formal presence of hunting and gathering camps. These upland camps would have been inhabited only during part of the yearâ&#x20AC;ŚThis pattern of upland hunting and gathering camps gave way to only rare hunting visits during Middle and Late Woodland periods. The floodplains have the potential of containing deeply buried archeological deposits although such sites have not as yet been reported in the study areas. [The collection contains] rhyolite Selby Bay points (200-900 AD) which suggest that people from the Tidewater area may have been hunting in this area.
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The Orient Fishtail and Dry Brook Points indicate that these Potomac based groups were travelling up Goose Creek to possibly hunt and gather in the interior. The fully grooved ax dates to this period and is further evidence for camps being established in this area. This is the only area that yielded a Marrow Mountain point (5,000-4,200 BC). This area has the potential of containing a significant site of the Late Archaic Period.
expert. One can read about prehistory ad infinitum, but having a quantity of tangible evidence of human-landscape interaction makes the human story of Oak Spring come alive.
Recommendations In the future, it is strongly recommended that OSGF request that all future cultural finds by staff, interns, and guests be returned to OSGF such that additional information can be gleaned and a similar Pauley Collection can be built. More is out there to find.
Summary The collection reveals similar perspectives from two different authors written decades apart. Indigenous peoplesâ&#x20AC;&#x2122; use of the Goose Creek uplands was slow at first during Paleo-Indian times, but expanded dramatically during Middle and Late Archaic times (8,000-3,200 YBP). During those periods people were hunting the uplands and perhaps using seasonal camps. It is possible they used the same springs that drew the Fletchers, the Lufboroughs, and later the Mellons. During this time, in response to the Holocene Climatic Optimum, the region was generally warmer than today but still dominated by oak and hickory with pine. As agriculture expanded, human groups shifted to the fertile bottomlands of larger rivers, using the interior uplands much less frequently. Nonetheless, Oak Spring contains lithic material from each millennium since shortly after the start of the Holocene.
References 2017. Dr. Carole Nash, personal communication. Undated. Unattributed. Archeological Resources [of the Pauley Collection]. On file at the Oak Spring Garden Foundation.
The Boyd Pauley Collection is a remarkable resource assembled by an astute, observant man. Oak Spring is lucky to have had it documented, and interpreted by a regional
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S TONE W ALLS As a result of its geology and history, Oak Spring contains over two miles of stone walls with a construction period spanning settlement to recent times. Original field stone, exposed during the landscape’s transition to agriculture, lie stacked in the same lines as when they were laid. Other walls existed 100 years ago but have been repurposed to other areas. The Mellon period left its mark with tightly fit, sharp walls along the road and gateways. In general, Virginia lacks a strong tradition of stone fencing when compared to regions north of the glacial boundary. Nonetheless, three eastern regions are recognized for concentrations of stone walls: New York State and New England; Kentucky’s Bluegrass Region; and Virginia’s northern Piedmont and Blue Ridge (Lewes and Houston 2004).
Background Stone walls are most often built as fences to keep animals in, or out, of something. As a fence, a wall needs to be 4 feet tall, and may be composed entirely of stone, or as a shorter wall with a wood or wire rail on top. A lawful fence in Virginia in 1872 had to be four feet high (Lewes and Houston 2004). The lack of glacier-deposited stone, and an abundance of trees, meant most fencing was made of wood. The split rail, zigzag, or “worm fence” was the standard fence in Virginia for generations. This was followed later by the post and rail fence – popular until late 1800s. In 1871, 85 percent of fences in Virginia were wood (Lewes and Houston 2004). Although stone was absent from the coastal plain (as a result of geology) it was available from the Piedmont, westward.
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Some stone walls are not built as fences at all; many walls are built as repositories for unwanted stones taken from agricultural fields. Such stone dumps may resemble little more than a pile (called a clearance cairn) or may result in an extensive, well-stacked wall. Stacking them frees up pasture surface area for grasses. In Northern Virginia many walls developed haphazardly; cleared fields exposed regolith and the stones were piled up. This changed when affluence arrived. Rock walls were expensive to build and their elegance became a badge of wealth. It’s unclear whether this happened during the region’s first wave of wealth when settlers, prospering on rich soils, became middle-upper class – or whether it was the second wave of wealth when affluent northerners bought up old estates after the Civil War. Nonetheless, walls went up throughout Loudoun and Fauquier County from settlement onward, and especially during Mellon times.
Two Miles of Stones OAK SPRING’S STONE WALLS. █ Dry stacked wall of original field stone. █ Original field walls, rebuilt in recent times; some mortar added. █ Contemporary walls of Mellon era with imported stone, some chinking, and hidden mortar.
Most of the stones in Oak Spring’s walls are greenstone (meta-diabase) from the basaltic dikes that emerged through the old granites back in the Paleozoic. I estimate most of Oak Spring’s fieldstone walls are 90% greenstone and 10% granite. This corresponds closely to the ratio of rock outcroppings of the two rock types found at Oak Spring (see rock outcrop section). The Parent Material map created by Jim Sawyer for the Type 1 Soil Survey shows similar proportions (see soils section).
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The diabase rocks are irregularly shaped cobbles, with mostly rounded, weathered surfaces. Cobbles are generally 4 to 12 inches â&#x20AC;&#x201C; tennis ball to volleyball size with the largest stones tending to lie at the bottom of a wall. The granite rocks stand out as white, angular rocks in a wall of otherwise dark, or orange, irregularly rounded stones. The ground was prepared and leveled before laying stone, but stones donâ&#x20AC;&#x2122;t rest deeply below. The walls on Peach Tree Lane and the parallel wall by the Broodmare Barn have American chestnut rounds stacked within the wall. These were placed to guide consistent wall width and taper during construction. I have not found anyone who is familiar with this style (or a name for it). These two walls are original location dry-stacked fieldstone walls composed primarily of diabase. In recent times they may have served as fencing for horses. But is it likely that the stones originated from the adjacent fields. Rocks were dry stacked, with no chinking. Some sections have very little lichen growth so must have been rebuilt in recent times when sections collapsed or leaned. Lichen growth could be used to relatively age the walls. Heavy lichen coverage is found on rocks in walls that have remained standing for many decades. There is very little lichen growth on the roadside walls made from quarried, imported (regionally) stones.
RED LINES SHOW ORIGINAL STONE WALLS at Oak Spring in 1937 as interpreted from this aerial photograph. It is difficult to discern walls from wood fences in the imagery.
The short section of wall in the woods above Goose Creek (at the south end of the forest) was unfortunately quarried away in 2017 and placed as rip-rap at the spillway base of the Lower Pond dam.
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Dry stacked, local field stone, wall above the Broodmare Barn. Note the limited lichen growth.
Quarried stone in a Mellon era wall along the road. These walls have mortar and chinking. The top rails are American chestnut.
Original dry stack wall in the forest slope down to Goose Creek. This wall has a curious history; see text.
Original dry stack wall of local field stone along Peach Tree Lane. Note the lack of lichen growth and the American chestnut guides in the middle.
A wall from the cemetery. These rocks appear granitic, but not rounded as the local field stone. Note here the amount of lichen growth on the rocks suggesting it has been in place for some time.
This dry stack wall occurs along the northeast boundary. Most of this wall is in fine shape, however, seen here a fallen tree is collapsing a portion. Trees are the primary threat to walls.
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In researching Oak Spring’s deed history at the county office, I found numerous references to “stone fences” in written records. Robert Fletcher’s will dated to 1841 contains a map showing existing walls on Peach Tree Lane and the fence on the northeast boundary going from upland fields through the steep forest to Goose Creek (it also shows the forest). Going farther back, local deeds from the 1810s mention stone fences here and there as part of the meets and bounds description, but it is unclear where these fences are (on or off Oak Spring). Nonetheless, considering the ~1820s date of the house, and these deed references, I am confident that Oak Spring’s first generation walls date to early 1800s from in their existing location, making them ~200 years or older. It would be interesting to research the amount of original stonewall built per area of land (in linear feet per square mile, for example). In other words, how much rock was available and how many miles of wall were built in each square mile of land? At Oak Spring alone, the local fieldstone yielded 8,500 linear feet over 260 acres. The forest at Rokeby, which has never been cleared for pasture or crops, might reveal how much stone is contained in upland soils around Upperville, and how deep it lies below ground. Most likely the walls were built over time as the land was worked and settled. As plowing uncovered stones, they were added to the walls. After Paul Mellon took ownership, walls were rebuilt, repurposed, and/or replaced. Lichen growth weathering may be the only way to interpret if a wall has been significantly altered in the past.
I believe the original dry-stacked walls at Oak Spring were built as stone dumps to remove stones from fields. A study in adjacent Warren County arrived at the same conclusion (Lewes and Houston 2004). This hypothesis, however, is challenged somewhat by the section of wall in the forest that runs down the steep slope to Goose Creek. Clearly, no one was farming that slope; the topography is too challenging and the old growth trees indicate the site has always been forested. Therefore, the wall must have been created as a fence to keep animals on one side or the other. As shown in plat maps, that wall was a boundary between the Fletcher farm (Oak Spring) and the John Wren Farm to the north. But with both sides of the wall having always been forest the full history is unclear. The wall must have been a fence that doubled as a property line. This would have made a more permanent boundary than using the wood that was obviously available in the forest. The slopes on the adjacent property hold abundant loose fieldstone; building a wall would have been simple. The woods on Oak Spring’s steep slope were grazed so a fence would have been needed. As the 1841 map from Robert Fletcher’s will shows, trees were in short supply and thus may have necessitated the use of stone for fencing. Oak Spring’s walls are one of the best and most treasured features on the property. They are unique for Virginia, and having so many vintages of wall totaling over 11,000 linear feet in a relatively small area is special.
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Management
References
A few words on stewarding stone walls:
Lewes, D. and K. Houston. 2004. Claiming Rocky Ground: Documentation of stone walls in the proposed Gooney Manor loop road historical district, Rt. 631 widening project, Warren County, Virginia. William and Mary Center for Archeological Research.
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Consider contacting Virginia Department of Historic Resources to record Oak Spring’s historic walls.
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Try to find written sources that have documented local rock features. (According to Lewes and Houston (2004) historic land records rarely offer information as property inventory was typically limited to movable property such as slaves, stock animals, machinery, furniture, etc.)
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Prevent removal or destruction of existing walls.
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Prevent exotic vines from climbing on walls.
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Prevent trees from growing too close to walls (3 feet minimum) and from falling on walls. Remove trees already fallen on walls in the forest.
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Begin documenting lichen growth on walls with known ages to develop a metric for estimating a wall’s age. Consider a photo documentation series.
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Rebuild sections of collapsed walls (Peach Tree Lane, some areas in the forest)
Scheel, E. 2017. Personal communications at Oak Spring.
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F LETCHER /R OKEBY C EMETERY Oak Spring contains a ½-acre cemetery south of the Main House and Spring House. It contains approximately 38 named graves ranging from 1841 to 1922, with an additional grave from 2009. Only about ¼ of the cemetery has burial plots. Robert Fletcher established the cemetery after his wife died in 1841. He legally established it in his will in 1845. The Fletcher family lived at Oak Spring for several generations from 18291929. After Paul Mellon bought the property in 1936, an agreement was reached that he would maintain the cemetery with “perpetual care and maintenance” in exchange for a 60 by 79 foot section of the cemetery. In 1948 when the agreement was signed, $20,000 was deposited at the Marshall Bank and Trust Co. in Marshall, Virginia, the income from which would
be used for the maintenance of the cemetery. Details of this agreement are below. Over 60 stones lie in the cemetery, but only 38 have names. The earliest birth year in the cemetery is Robert Fletcher, born 1777. The earliest death is Ann Elizabeth Fletcher (neé Whitford) in 1841. Overall there are 20 Fletchers, 7 Lakes, 5 Chappelears, 3 Robinsons, 1 Rucker, 1 Stickel, and 1 Isabell. There are over 20 unmarked stones. Seven children are buried in the cemetery; five aged 1 year or less, one aged 4, and one aged 6. Excluding the children, the average age at death was 59.8 years. With children included it is 48 years. Most recent burial is Robert Isabell in 2009. Before that, Cathrine Fletcher was buried in 1922. Paul Mellon’s first wife, Mary Conover Mellon, was buried in this cemetery in 1946, but later was moved to Trinity Church in Upperville.
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Slightly outside the cemetery, to the south, is a burial stone flush to the ground with the name Christmas Goose. Christmas Goose (born in 1965 and died in the 1980s) was Paul Mellon’s favorite horse with which he rode the 100-mile trail rides through Virginia (and won).
According to the deed, the following conditions (generalized) are placed on the cemetery (see deed for details): •
It may be used only as a cemetery
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Shall be kept planted with a cover of ivy or myrtle and wild flowers with no elaborate or formal planting or boxwood bushes.
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Trees shall be kept in good condition and new trees planted as necessary.
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The stone wall with rail rider will be kept in good condition.
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All burial stones kept free of ivy and only modest stones will be placed.
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Will be kept free of briars and brush and will be kept neat in appearance.
Fletcher/Rokeby Cemetery: Burrials by Decade 8 6 4 2 0 1840 1850 1860 1870 1880 1890 1900 1910 1920 2000
It is possible that slaves may be buried in the cemetery. Often slaves were buried in the family cemetery without stones, or buried slightly outside (Eugene Scheele, personal communication). Unmarked stones may also mark slaves. Eugene Scheele and I observed several depressions on the far side of the cemetery that could be graves, however, I also believe they could be locations of decomposed tree stumps.
The current condition of the cemetery includes several large old trees including a bitternut hickory and black walnut. Ornamental trees including holly and boxwood grow on the peripheries. Vinca sp. grows in and among the stones, and recent work was done to eliminate brush and overgrowth. Some daffodils occur, and additional perennials could be planted. Stones are for the most part intact, however, some are leaning and/or cracked.
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References Findagrave.com. 2017. Fletcher/Rokeby Cemetery, Fauquier County, Virginia. https://www.findagrave.com/cgibin/fg.cgi?page=cr&CRid=2367653 DEED and AGREEMENT provided by Oak Spring.
PORTION OF THE CEMETERY GRANTED to Paul Mellon by the Fletcher family shown in the southeast corner.
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O AK S PRING P ROPERTY H ISTORY
“Beginning at four hickories on the bank of Goose Creek….”
Oak Spring’s land ownership history begins with American Indians. How they understood or interpreted land ownership, however, is impossible to know. European claims reach back to Thomas 5th Lord Fairfax in 1649. The Treaty of Albany, in 1722, ceded American Indian claims to the lands east of the Blue Ridge. Thomas 6th Lord Fairfax’s Northern Neck Proprietary was formalized sometime after this.
unknown. Many Fletchers made numerous land transactions in the area between 1800 and 1830.
Through the Fauquier County Land Records Office in Warrenton, I attempted to trace Oak Spring’s deed back to Fairfax. The Fauquier County records go back to 1759; before that year what is now Fauquier County was part of Prince William County and thus records are stored there. The land records are difficult to follow.
Year Seller/Deceased Buyer/Heir 1936 Emma and Gordon Grand Paul Mellon 1929 Tacie Fletcher Slater Emma Grand 19?? Robert Fletcher Tacie Fletcher 1900 Albert Fletcher Robert Fletcher 1880 Willie and Anna Fletcher William Fletcher 1845 Robert Fletcher William Fletcher* 1829 Aquila Glascock Robert Fletcher* 1822 William Rust Aquila Glascock 1816 George & Edward Carter William Rust 1779 Landon Carter (Through numerous heirs) 1731 Robert Carter Landon Carter 1720s Lord Fairfax Robert “King” Carter *See details below on Robert Fletcher’s will.
I traced the core Oak Spring property back to 1816, and found references to earlier transactions. Robert Fletcher was a key landowner in the area and began the Fletcher era at Oak Spring. However, it appears that while Robert Fletcher owned a number of properties adjacent to the core Oak Spring parcel beginning by at least 1817, he didn’t own the main property until 1829. Thus it is unclear if he built the “Fletcher Cabin,” the original house that stood on the footprint of the Mellon Main House, or if it was built earlier. The house is shown on an 1841 survey, but its year of construction is
Nonetheless, deed history includes 200 years of clear ownership history (to 1816) on the core property with earlier Carter family ownership poorly understood:
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1841 Will of Robert Fletcher Robert Fletcher drafted a will after the death of his wife in 1841. He updated the will in April 1845 and died later that year. The will detailed what should become of his land, furnishings, cash, and slaves divided among his seven children. He had the property surveyed in 1841 and a plat of is included in the will.
No. 3: Henderson Tract • 25-acres from Moses Glascock 1826 • “A few-acres” from Glascock 1821 • 81-acres from John Wren in 1817 • 29 ½ -acres from John Smith 1820 • 7-acres from John Smith 1817 • Finch Lot from Rob Armisted in 1836
To share the property with his descendants, Fletcher divided the farm into three tracts: the first which includes the Fletcher cabin (labeled on the plat as “Home or Mansionhouse”), cemetery, and core of what is today OSGF.
CEMETERY Robert Fletcher also detailed the ½-acre family cemetery in his will. The cemetery is covered in a different section.
To amass the farm at its 1845 size – over 450-acres, Fletcher purchased the parcels as follows listed among the three parcels created by his will:
SLAVES It is worth recognizing from Fletcher’s will his six slaves who presumably also lived at Oak Spring. All were willed to his descendants and include the following names:
No. 1: Home or Mansion Farm: • 260 acres from Aquila Glascock in 1829 (this is the core of the current Oak Spring Garden Foundation). • A “small” undated purchase from Nathaniel Lufborough (spelled with one “f” in the will). No 2: Wren tract: • Purchase from Glascock 1821 • 28-acres from Edward Carter in 1820 • 7-acres from Armisted in 1830
• • • • •
Girl Catherine and daughter Mary Ellen Boy James Charlotte Mountain Henry Billy
For the purposes of accounting Fletcher’s estate Henry and Billy had values placed on them of $625 and $600 respectively ($15,700 in 2017 dollars). Eighteen years after Fletcher’s death the Emancipation Proclamation and Civil War would free them.
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PLAT SURVEY INCLUDED IN ROBERT FLETCHER’S 1841 will. Plat (left) taken from Fletcher’s will. Fletcher divided the ~450+ acres into three parcels for his sons. The No. 1, or Home Mansion parcel is left and includes the Fletcher cabin drawn in. With the house, “Spring Branch” is drawn, which includes the site of the current (Mellon era) springhouse. At right, the same plat is laid on contemporary imagery. It is remarkable how many of the hedge rows still line up. The Fletcher’s farm included lands now part of the Brick House, but did not include the Lufborough tract, which now holds the barns and glass house. It’s not clear when the Lufborough tract was added, however, Robert Fletcher did purchase a few acres from Nathaniel Lufborough at some point before 1841.
EARLIER TRANSACTIONS AND HISTORY Prior to transactions noted in Robert Fletcher’s 1841 will, the property is difficult to trace. Robert Fletcher was making many land transactions as buyer and seller. Additional surnames involved of most of these transactions include Glascock, Wren, Rust. Many transactions were leases not sales. Some were for parcels as small as 7-acres.
The field stone Fountain Hill House (across the road from Oak Spring) was built in the 1790s by Joshua Fletcher on land originally owned by the Carter family. Joshua Fletcher (1750 (Wales) – 1811) was father of Robert Fletcher (1777-1845), of Oak Spring.
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The National Register of Historic Places (NPS 2006) report for Fountain Hill indicates the property was originally part of a 9,699-acre tract on the north side of Goose Creek granted to Landon Cater, son of Robert “King” Carter, agent for Lord Fairfax. Landon died in 1779 and his sons John and Landon II inherited the land. John’s son John, leased the land to Joshua Fletcher in 1794. The chain up to John and Landon II is likely the same land tenure for Oak Spring. However, an early Oak Spring deed from 1816 notes the property was originally granted to Landon Carter as part of a 5,487-acre patent.
“Oak Spring Farm” and “Rokeby” References are made to “Oak Spring Farm” in the 1929 deed transfer from Tacie Fletcher to Emma Grand including 271acres, that is today the main part of OSGF. The 1900 deed transfer between Albert and Hannah Fletcher to Robert Fletcher refers to the property “known as Oakley Hall, containing 271 acres….” There is an “Oakley Farm” in Upperville, however, there is no indication from these deeds that they have been connected since the mid-1800s. It’s unclear when exactly “Oak Spring” was coined, but many farms had such names early on.
1903 SURVEY BY JOSHUA FLETCHER from Tacie Fletcher Slater to Emma Grand 1929 deed transfer (deed book 133, pg. 19). North is to the right. This parcel is the “Home or Mansionhouse” as divided by Robert Fletcher in his 1841 will. West side includes property that is today part of the Brick House. Note the speckled forest areas, as they are today. Note land adjoining to northwest owned by M. Peach, which could be the namesake for Peach Tree Lane.
The “Rokeby” Farm, across the street from Oak Spring, and the operations base for the Mellon Estate, is described on a typed paper provided by longtime Rokeby manager Aileen Laws. It states that the farm was already named Rokeby when Mellon purchased it in 1931. The farm name may have its origin in a stallion named Rokeby foaled in 1827 and belonging to Nathaniel Lufborough, an early property owner
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of the land that today includes Loughborough Lane (spelling change), the glasshouse, and barns and quite possibly the land of Rokeby Farm. Reaching farther back, a famous house in England is called “Rockeby” in a poem by Sir Walter Scott. Oak Spring’s Loughborough tract should also be traced.
Landscape Features Information is contained about the land in these early deeds, especially with regard to the trees. The surveyors inadvertently built a database of randomly selected trees from settlement times. In a quick read of early deeds around Upperville, the following trees are mentioned in decreasing frequency and these roughly approximate current relative abundance: • • • • • • • • • • • • • •
References and Resources Much of this information was gleaned from records in the Fauquier County Land Records office. Fletcher, Robert. 1845. Robert Fletcher’s Will. Will book 19, Page 298. Fauquier County Land Records office. NPS (National Park Service). 2006. National Register of Historic Places Registration Form: Blue Ridge Farm. Department of the Interior. https://www.dhr.virginia.gov/registers/Counties/Fauquier/0300894_BlueRidgeFarmm_NRfinal_2006.pdf
White oak (Quercus alba) Red oak (Q. rubra) Hickory (Carya spp.) Spanish oak (Southern red oak) (Q. falcate) Walnut (Juglans nigra) Box white (post) oak (Q. stellata) Dogwood (Cornus florida) Sassafras (Sassafras albidum) Chestnut (Castanea dentata) Maple (Acer sp.) Beech (Fagus grandifolia) Ash (Fraxinus spp.) Sycamore (Platanus occidentalis) Plum (Prunus americana)
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S PECIAL P LACES Many of Oak Spring’s special places have been introduced and described earlier in this document. For example, the old growth section describes those special trees. The section on Goose Creek describes the stream, and the stone wall section reveals Oak Spring’s original 200-year old walls. What follows is a listing and description of the best special places. These are the features OSGF will want to highlight, bring people to, and use as defining landscape features. The first group includes Natural Features such as the forest and trees. The second group includes features from the Cultural Landscape such as important stone walls and Mrs. Mellon’s oaks. The third group includes those spaces that are special, not necessarily for their ecological, historical, or interpretive value, but just because they are scenic, quiet, or beautiful.
Some sites are particular points on the ground, such as a stone wall, or a tree. Others are broader areas of forest, landscape, or stream. It will be important in these areas to preserve what is there now by not over-developing or adding too much infrastructure. This group of special places is relative to the entire property and also my perspective (and biases) and scope. For example, nothing of the Mellon Residence, or other infrastructure is included other than the block on the Pony Barn with Robert Fletcher’s initials. However, much could be included among those sites, inside the doors of the residence, the basket house, and more. Every spot at Oak Spring tells a story and has been touched by the Fletchers, Mellons, or others. A map follows with numbered features corresponding to descriptions that follow.
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SPECIAL PLACES AT OAK SPRING. As shown, some are broad areas, while others are specific locations. Some sites have overlap between Natural and Cultural.
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
Natu ral Wren Run Ravine Old Growth Goose Creek at Cliff Rock Rock Meadow Woodland Garden Gateway Rocks Open Grown White Oak Largest White Oak Oldest Black Gum Mrs. Mellon’s Willow Oaks Spring House Lufborough Springs Cobblers View Blue and Bull View
15. 16. 17. 18. 19. 20.
C ul tu ral RF 1833 Fletcher Cemetery Lufborough Place Eliza’s Woods Peach Tree Lane Old Goose Creek Ford
21. Original House and Garden 22. Chestnut Rails (at large)
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1. WREN RUN RAVINE
2. OLD GROWTH
This site is named for the scenic drainage area and the adjacent (former) Wren farm. John Wren owned the property sometime before 1820. A number of features come together here making the site interesting and scenic. The spring fed stream drops over a small waterfall. At the top of the drop is an ancient Liriodendron (tulip tree), which formerly stood in open pasture. Oak Springâ&#x20AC;&#x2122;s only witch hazel also occurs here. And an original 200-year stone wall lines the property on the north side and makes for a scenic and historic edge to the woodland. The layers of nature and culture at this site are thick and interconnected. See the Young Woods description in the Vegetation Inventory and Stone Wall section for additional details.
Though the Old Growth stand spreads throughout this forest, this mapped area, centered on the ephemeral drainage beginning at the small young woods, is the best part. Here 280-year old white oaks tower over the steep slopes, the 320year post oak stands hidden among other elders, and spring ephemeral flowers show their best display. As exotic vegetation is eliminated, the area will become much richer. A stand of pawpaw and Virginia bluebells (shown) hem in the north extent, and the southern reach has an open slope. A couple of dead cedar trees indicate former pasturing and additional light in the canopy. The lack of basal scars and stumps indicated limited disturbance over the past century. See the Old Growth summary in the Vegetation section, and the Trees subsection.
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3. GOOSE CREEK AT CATOCTIN CLIFF
4. ROCK MEADOW
This is one of the most scenic spots on Goose Creek. Here, the stream bends around to the left as it pushes off a large rock outcrop on the far side (off property). The rock appears to be diabase (greenstone). A deep pool on the far side reflects the cliff while a gravel bar on the Oak Spring side affords access. Large black walnut trees frame the site with a large ash suffering from emerald ash borer. A couple of large stone blocks (for flood resistance) would invite sitting. The adjoining property on the far side contains old growth trees that were never cut on account of the steep cliff. Bald eagles nest nearby. See the Goose Creek section.
This scenic and ecologically important area is open grassland with over 20 rock outcrops â&#x20AC;&#x201C; the greatest concentration of rock outcrops at Oak Spring. Most of the rock outcrops are diabase (greenstone, see geology section), but two are granite (shown). Raptors perch on the taller rocks, and groundhogs, foxes, and small mammals den among the larger rocks. With the native warm season grass transition and the addition of scattered trees, this area will become all the richer. Excellent views can be had on the higher promontories.
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5. WOODLAND GARDEN
6. GATEWAY ROCKS
This area is named for its great potential as a shady woodland garden. This site packs in more physical diversity than any other site. The small ravine on Spring Branch offers a lush, if weedy, composition â&#x20AC;&#x201C; in dramatic contrast to the sunny, open, conditions over much of Oak Spring. Three settlement era pasture oaks spread branches over the young successional woods that reach back 100 years. There is a small bedrock waterfall (shown), which could be a centerpiece for this future woodland garden. See the vegetation description for this site.
This is the largest, and perhaps most scenic rock outcrop at Oak Spring. Composed of diabase, the outcrop contains several large areas. In 2017 it was ringed in Japanese honeysuckle, however these were eradicated. Creative plantings here could take advantage of the xeric conditions around the rocks. The rocks form a gateway of sorts to all of Oak Spring, but especially to the long walking lane that runs to the north between the fences. See the Geology section.
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7. OPEN GROWN WHITE OAK
8. LARGEST WHITE OAK
The white oak (with the white bench) at Spring House Pond tells a rich story. The 53-inch diameter tree has a beautiful, well-tended form. The huge, 20-inch diameter branches suggest an always-open growing environment. Tree rings reveal the tree is ~257 years old (1760) while the upper branches age 215 years (1801). This indicates the tree has been open-grown for all or nearly all of its life. What kept the early Oak Spring landscape open in the late 1700s? Fire could have, or early clearing from settlement. After 1722 American Indians remained on the west side of the Blue Ridge. However, with the spring close by they could have been using this location in the decades up to the treaty. The tree has cavities up high that house bats or other mammals.
This colossal white oak has a diameter of over 60 inches. Like the white bench oak, it too, also appears to have always been open grown. The tree had thick undergrowth and fences to keep horses away until that was all cleared in 2017. Itâ&#x20AC;&#x2122;s a remarkable tree that, because of its topographic position, is easy to miss. It should be a site on any ramblers walk.
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9. BLACK GUM: OLDEST TREE Nyssa sylvatica (Black Gum) is the longest living broadleaf tree in North America. The oldest known individual is in New Hampshire and has been aged to 697 years (2018). Trees in the 500-year range are somewhat common. The species is extremely shade tolerant, but also often follows disturbance. It rarely ever makes up more than 1% of basal area in a forest. This individual at Oak Spring is approximately 400 years old. This estimate is based on a partial ring count (the tree is hollow), an interpolation based on the amount of missing core, its growth rate, and other factors. The tree could be 500 years, or as young as 350 years. To the treeâ&#x20AC;&#x2122;s southwest stands another black gum by the neighborâ&#x20AC;&#x2122;s driveway. This tree is approximately 301 years old. Black gum trees in the forest are over 200 years.
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10. MRS. MELLON’S WILLOW OAKS
11. SPRING HOUSE
Just outside the residence, below the dining room, stand two willow oaks (Quercus phellos). One tree is an enormous character – well pruned, vigorous, and wide spreading. The diameter is 55 inches. The trees appear on aerial imagery faintly in the 1960s. One of the trees reveals a ring count of 48 years in 18 inches. Estimating for the missing core yields a tree between 65-70 years. According to Ronnie Caison, a long time Oak Spring house manager, Mrs. Mellon said she planted the trees. Considering the house was built in 1951, this agrees with the age based on rings and imagery. The trees are similar in age to the willow oaks planted near the president’s house.
Below the front entry of the residence is a springhouse and the spring it contains is the ultimate reason why all other human endeavors exist at Oak Spring. It is this spring that first attracted the Fletchers to built their log home on the exact footprint of the current residence. Every settler needed a water source, and it was this spring that served this property. It is likely that this spring served people for thousands of years. The purpose of a springhouse in was to contain the water and make it available through a pipe or other outlet. The house creates a room that stayed cool for refrigeration. See the Springs section.
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12. LUFBOROUGH SPRINGS
13. BLUE AND BULL VIEWS
North of the barns and Audubon House are two springs. They rise in open meadow and sedges, rushes, and cattails (shown) indicate the hydric conditions of the site. There is often standing water. These are the Lufborough Springs, so named for Nathaniel Lufborough who settled the property around the time of Robert Fletcher. Just as the Spring House (site 11) served the Fletcher family, these springs would have served the Lufboroughs and is the ultimate reason why their farm was located here in the early 1800s. A springbox installed during Mellon times remains. Today these springs serve as the water source for Wild, Tree Shop, and Lower Ponds. In time the springs and the Spring Branch below it will be planted in wetland vegetation.
From this area, the rambler is offered excellent views of mountains to the west and east. To the west, six miles away, the famous Blue Ridge Mountains rise to 2,000 feet above sea level (~1500 feet above Oak Spring). While to the east, 10.5 miles distant, the Bull Run Mountains (shown) stand at 1,300 feet high. Here, one is looking at the bounds of the north trending Loudoun Valley, the edges of Fauquier County, and the remnants of a grand geological story. See the Geology section for more.
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14. COBBLER VIEW
15. RF 1833
This location on the ridge above the Lower Pond dam offers one of the nicest and quietest views at Oak Spring. In the foreground Oak Spring property leads down rolling terrain to Goose Creek. More distant, 8 to 10 miles away, stand the Broken Hills, a series of low broken up ridges that hem in the southern end of the Loudoun Valley. Dominating the line is Big Cobbler and Little Cobbler Mountains, which stand at 1,500 feet. Lower ridges include, Swain’s Mountains, Watery Mountains, and Pignut Mountain.
This stone on the Pony Barn is etched “RF 1833” presumably by Robert Fletcher and built in the year 1833. Fletcher purchased the property in 1829 and began building shortly thereafter. A document by Jean Brydon Robinson from 1986 suggests the Pony Barn was replaced in 1915 and the old stone incorporated into it.
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16. FLETCHER CEMETERY
17. LUFBOROUGH PLACE
The Rokeby-Fletcher Cemetery is described in detail in that section. Briefly, the earliest death date is 1841. There are 60 stones, however, only 38 are named. Some of the unnamed stones could be slaves. Just outside the cemetery is a section of diabase rock outcrops and a 200 year old black walnut tree. See the Cemetery section for more details.
Loughborough Lane is named for Nathaniel Lufborough who settled and lived on the property today including the Audubon House, Glasshouse, and barns. The barns are original, however, it is unclear when in the 1800s they date to. Fletcherâ&#x20AC;&#x2122;s property wrapped around it to the north. As described in site 12, the springs formed the primary draw and the property mainly stretched north. In a 1901 survey, Joshua Fletcher was listed as the owner; however, it is unclear when he bought it from Lufborough. It is also unclear when Paul Mellon bought it and if that was from Joshua Fletcher or someone else. Perhaps architecture of the barns can reveal when the structures were built.
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18. ELIZA’S WOODS AND POND
19. PEACH TREE LANE
The pond in this location is named for Mrs. Mellon’s daughter Eliza, and I have extended the name here to include the grove of trees surrounding it. The trees in this grove include willow oaks, Tilia sp., Pagoda tree (Styphnolobium japonicum), Ginkgo, Amelanchier sp., American beech, Magnolia sp., and others. Until at least 1969 this area was fenced and contained no trees. By 1974 it was made into a tree nursery. Oak Spring staff informed me that these trees seen today were nursery stock that had never been transplanted. The pond was built in the 1950s (see Ponds section). It is fed from a spring occurring just outside the wall on the west side.
Peach Tree Lane runs 0.25 miles from Rt. 623 to the Main House. The name has been in use for a long time and its origin is unclear. The 1901 plat shows “M. Peach” owned property across Rt. 623 from Peach Tree Lane. This was the original entrance into Oak Spring; the route appears on the 1901 plat and 1937 aerial photo. Also visible on the 1937 photo was an orchard in the field north of Peach Tree Lane. Perhaps these were peaches. In 1930 Rt. 623 was moved approximately 100 feet west; the original line is still visible. Peach Tree Lane showcases one of the few granite outcrops found at Oak Spring. A couple of bore holes occur in them for an unknown purpose. The stone fence on Peach Tree Lane is original. It is composed mainly of diabase, however, it has more granite in it than other walls. American chestnut wood is embedded within as guides during construction.
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20. GOOSE CREEK FORD
21. MAIN RESIDENCE AND GARDEN
Near the confluence of Spring Branch with Goose Creek, the creek widens in a section where no trees exist on the far side (off Oak Spring property). During periods of low water, one can see a stone causeway crossing Goose Creek from bank to bank. I believe this is an old ford, as across the bottomland on the far side an old farm track cuts up the wooded slope. This old farm path does not appear on any old maps that I have seen.
Volumes could be written about the Mellon residence. For the purposes of this document and Oak Springâ&#x20AC;&#x2122;s changing landscape, a few points are worth noting. First, the Mellon house was situated on the exact footprint of the earlier Fletcher log cabin. The cabin was moved across the road when the new Mellon residence built in 1951. Second, the previous house also had a garden in the back. Again, the Mellon design fell onto the exact same footprint for the perimeter of the garden. The observant gardener will note the north (rear) wall of the garden is at an acute angle. This same garden perimeter and angle is visible on the 1937 aerial photograph (left) compared with contemporary times (right).
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22. AMERICAN CHESTNUT FENCE RAILS This special feature is an â&#x20AC;&#x153;at largeâ&#x20AC;? site because one can find these old American chestnut fence rails all over Oak Spring. (One can find them all over upper Fauquier.) American chestnut (Castanea dentata) was widely used for fences and other outdoor applications because the wood is remarkably rot resistant. The chestnut blight arrived to New York in 1904 and reached Virginia by 1914. These rails are at least that old (103 yeas). Some cross sections reveal 60 years of growth making them pre-Civil War era trees. The Blue Ridge contained high densities of chestnut so it is possible these rails were cut from there either as salvage as the blight went through, or before. Stacked end to end, Oak Spring may have 4 to 5 miles of chestnut rails.
Spring beauty Claytonia virginiana
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P ART 3: M ANAGEMENT S YNTHESIS Part of creating is understanding that there is always more to do; nothing is ever completely finished. –Rachel Mellon
In Part 1 we placed Oak Spring in a broader background context: geology, the forest, the presettlement landscape, and the regional human history. Part 2 provided a detailed inventory of Oak Spring: rock outcrops, stone walls, the trees and vegetation, historical relicts, special places, and more. Part 2 also offered a number of management suggestions for ponds, wetlands, and other features. In Part 3, we look to Oak Spring’s future. Considering where Oak Spring has come from (the regional background context), and what the site holds now (the inventory), what should Oak Spring look like in 50 to 100 years? What’s the best way to get there? Here we look at regional conservation context, future climate, and then the specifics of intentional vegetation change at Oak Spring.
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C ONSERVATION C ONTEXT When viewed from space, Oak Spring lies in a sea of green. Light green squares, rectangles, and other polygons show pastures, hayfields, and other open lands. Fields dominate upper Fauquier and stitch it together into a patchwork quilt. Breaking up this intricate geometric pattern are splotches of dark green – linear and irregular shapes. These features highlight the region’s geology as much as its ecology as forest areas are concentrated on mountain ridges, hills, and sloping drainage ravines. Topography spared them from clearance and keeps them dark green. Present day delineations of forest and field in upper Fauquier County have been in place, more or less, since at least 1937 (the first aerial photos show forest areas were largely the same as they are today). Since 1956 (first available online aerial images for which broad comparison is possible) there has been essentially no change in forest blocks over ~10 acres (added or removed) in upper Fauquier. The forest and field arrangement at Oak Spring has been in place since the mid1800s as shown on Robert Fletcher’s 1841 plat. The landscape transformation from presettlement times to something resembling today’s arrangement of green happened in barely a century. Forests were left in places unsuitable for agriculture: steep slopes, wet woods, and small woodlots to serve the needs of farms.
As was discussed in the background context section of the Presettlement Landscape, Virginia’s northern Piedmont has always been a mosaic of forest and field. American Indians hunted and burned, opening vast areas of savanna on the edges of a mostly forested region. Thus, Oak spring is embedded in a fragmented landscape. As a result, the conservation challenges at Oak Spring (exotic species, limited forest core area, extirpated or uncommon native species, overabundant deer, exotic-dominated grasslands, etc.) are the same issues seen at a larger regional
YOUNG BLACK BEAR in Oak Spring’s forest above Goose Creek. (Photo: Virginia Working Landscapes)
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scale and are a result of a fragmented landscape – ultimately are a result of the region’s agricultural history. Upper Fauquier today is roughly 75% open and 25% forest. To the west, 7 miles away, the Blue Ridge Mountains form a core ecological area. The forested spine of the ridge runs nearly unbroken for 200 miles, through mostly protected government lands. Although valley forests lack connectivity to the core, the small forest islands are valuable (see bear photo). This speaks to the landscape’s potential; a long-term goal for the region could be to expand the sizes of valley forest blocks, and to reconnect those blocks to the forested Blue Ridge core. Such restoration will happen one property at a time; when landowners decide to manage their land differently and take
on the challenge of eradicating exotics, replanting with natives, and rewilding the region. Oak Spring’s neighbors are correcting land uses of the past – mainly a focus on exotic grass management for the benefit of horses – and planting native warm season prairies and savannas. It will be a slow process; rebuilding a forest is a century-level commitment. Can this fragmented landscape be rebuilt? Current economic drivers of human land use, exotic plants, overabundant deer, and a warming and wetter climate leave an uncertain future. But the list of uncertainties 150 years ago could be equally as long, and we still find rich, diverse, Piedmont landscapes embedded in the agricultural matrix. We approach the land knowing that the potential is huge, success is uncertain but has high rewards for people and nature, and perhaps none of us will experience those rewards in our lifetimes.
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CONSERVATION LANDS IN THE NORTHERN PIEDMONT. Map by the Piedmont Environmental Council. Oak Spring is located by the red star in an area heavily protected with easements. Though the lands are held under easement and further development is restricted, the lands are primarily nonforested agricultural lands similar to Oak Spring.
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A report by the National Wildlife Foundation (Kane et al. 2013) summarized the current understanding of projected climate shifts in Virginia and modeled select species responses.
Kane et al. (2013) examine a variety of species with modeled range shifts over the next 100 years. For most current Virginia species, the shift leads to reduced frequency, but rarely extirpation. However, as common sense would suggest, species with a more northerly present day range (spruce, yellow birch, etc.) show lower future frequencies, while species with deeper southern ranges show future success in Virginia. The various models disagree on the long-term climatic range for various species with one showing, for example, extirpation under a low emissions scenario, and range expansion under a high emissions scenario. Of course the range shift models are based solely on climate and do not consider other ecological processes; this is an important fact considering species’ ranges are not driven by climate alone.
The report used the Governor’s Climate Action model, which projects that by 2100 Virginia’s average temperature will increase by 5.6°F (3.1°C). A different model used by the Chesapeake Bay Science Program predicts a temperature rise from 4°F to 11°F under various emissions scenarios. Both models predict roughly a 10% increase in precipitation falling mainly in winter and spring (consistent with recent flow trends on Goose Creek). In addition, Kane et al. (2013) suggest increases in temperature and precipitation are likely to result from extreme events and that while such events are tempered somewhat by overall averages, these events can have critical consequences for plants and animals.
Considering the reliability of contemporary modeling, it is hard to say precisely what ecological community Oak Spring will foster in 200 years. The simplest guideline for species selection might be to avoid species for which Virginia is currently on the southern margin of their range. For example, it is tempting to include Bigtooth Aspen in clusters in the savanna areas. The species is native to northern Virginia and it commonly grows in groves in early successional situations. It is an excellent wildlife tree. But even a slight range shift moves it out of the state. Aspen decline is occurring throughout the southern end of the genus’s range. Decline in paper birch is also occurring on the southern end of its range.
C LIMATE C HANGE It would be naïve to consider a long-term management plan that ignored Earth’s changing climate. Just as the fluctuating climate of the Pleistocene shaped the composition and function of ancient forest ecosystems, the changing climate over the next 200 years will have similar repercussions. For vegetation planning at Oak Spring, this essentially boils down to planting appropriate species.
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The other side of that coin is to proactively plants species for which Virginia is currently on the northern portion of its range. Post Oak, for example, currently ranges from New Jersey to Oklahoma, to Florida. The species has considerable slack in its southern range for shifting north with Virginia still suitable. Models suggest massive range increase (see image at right) to the north and east with high frequency expected in the Virginia Piedmont. Depending on how ecologists shape the philosophical debate on assisted migration, Oak Spring could consider introducing a number of southern plants that may be outside current natural range. Loblolly pine (Pinus palustris), for example, has a current range along the Coastal Plain from Maryland to Texas (not in Fauquier County). Models suggest its range will spread much further inland to include Kentucky and West Virginia. Should Oak Spring plant the species? The species may arrive on its own, in which case OSGF will need to decide if it is welcome. Again, the models account for climate and not necessarily soil type or other factors that limit a species’ range. The species listed in the sections that follow for the most part contain enough “range slack” to suggest they have a high probability to remain in Virginia in 100+ years. Some species, like swamp white oak, have more restricted habitat conditions making future range difficult to project. Such uncommon, northern, or specialist species are worth including.
RANGE SHIFT FOR POST OAK. Current distribution for Post Oak (left) and projected distribution under the average of three low emission scenarios. Source: Prasad et al. (2014)
CLIMATE RESOURCES Kane, A., T.C. Burkett, S. Kloper, and J. Sewall. 2013. Virginia’s Climate Modeling and Species Vulnerability Assessment: How Climate Data Can Inform Management and Conservation. National Wildlife Federation. Reston, Virginia. http://www.bewildvirginia.org/climate-change/virginias-climatevulnerability-assessment.pdf Prasad, A.M.; L.R. Iverson; M.P. Peters; S.N. Matthews. 2014. Climate change tree atlas. Northern Research Station, U.S. Forest Service, Delaware, OH. http://www.nrs.fs.fed.us/atlas
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V EGETATION P LAN Vegetation management at Oak Spring should seek to create conditions that are: •
•
Ecologically appropriate: Use native plants, have respect for the presettlement landscape, be attentive to deer populations, and consider anticipated climate changes. Diversity oriented: Redundancy fosters resiliency and by including a variety of species in plantings one adds insurance in the event of a blight. (And it adds beauty.)
And that: •
Reduce management costs: Some situations call for formal landscapes with high maintenance costs, but natural, sustainable communities reduce costs of mowing and maintenance over the long-term.
•
Provide for wildlife: though Oak Spring is a plantcentric institution, fostering diverse healthy wildlife populations adds richness to the landscape.
This vegetation master plan takes a broad, high-level approach. It is conceptual and instructive, but is not specific
enough to capture all the vegetation needs at Oak Spring. For example, each pond will need a planting plan to redefine the margins and showcase these unique areas. Additionally, the exact boundaries of reforestation and planted areas will be determined on the ground. Likewise, the locations of scattered trees, and the relative abundances of species within a mix, should be decided in collaboration, on the ground. In sum, a design element must follow for each project. The exotic plant infestation at Oak Spring has been contracted in 2018 for eradication and should be complete by 2021. It will be imperative that Oak Spring work with neighbors to encourage and inspire them to responsibly eliminate their infestations as well. Otherwise, seeds will drift and new plants will grow. The map below outlines broad areas for vegetation management. This includes: ~115 acres of grasslands or scattered tree savanna; ~40 acres of reforestation including 5 acres of Goose Creek floodplain. This will be the greatest improvement Oak Spring can make to water quality and habitat on Goose Creek. Additionally, the plan calls for: ~2.0 acres of wetland scrub shrub below the Loughborugh Springs; a ~1-acre Woodland Garden; two areas for visual screens; and nearly 11 acres of potential agricultural land scattered among four areas. Each cover type will be described briefly in sections following the map.
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VEGETATION PLAN
█ Grassland / Savanna █ Wildflower Centerpiece █ Reforestation █ Scrub-Shrub Wetland █ Visual Screens █ Woodland Garden █ Potential Agriculture █ Formal / Ornamental
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Grasslands: Savanna Base Layer In terms of acreage, the restored native grasslands comprise the largest vegetation change proposed. It involves the conversion of some 125 acres of cool season fescue grasses, orchard grass, and other exotics (as well as some natives â&#x20AC;&#x201C; see the summary of Virginia Working Landscapes inventory work in Part 2 for a list of existing species in grasslands) into native warm season grasses and wildflowers (NWSG). With the addition of scattered trees, a savanna landscape will be created. There are three primary variables to installing a NWSG meadow. Each is a moving target with a variety of options, and mixed published opinion. A final decision on each is dependent on budget tolerance, level of patience, and desired outcome. COMPOSITION Although savannas and large grasslands occurred in the Piedmont and other areas of the Shenandoah Valley in presettlement times (see Part 1), there is no clear agreement of what the community was composed of, nor the relative abundance of species. Virginia DCR (Fleming et al. 2017) lists a Piedmont Prairie natural community, noting, however, its unclear history. Vast areas of oak-savanna in the upper Midwest, occurred in historic times and ecologists have better information for those
ecosystems. But on account of its early settlement history, Virginia lacks solid documentation of those community types. This is both freeing, and also presents challenges. Itâ&#x20AC;&#x2122;s freeing because there is no right or wrong list when it comes to species composition for NWSG. The challenge lies in trying to be true to Virginiaâ&#x20AC;&#x2122;s natural communities and deciding which species to include. There are many resources available with suggested lists. The list provided here suggests the most common species that make up the vast majority of biomass in the community. It is an average of many lists. PROCESS Most sources suggest broad-spectrum herbicide is the most efficient and effective means for eliminating exotic cool season grasses. Considering the slopes at Oak Spring, disking and tilling will leave soils vulnerable to erosion. With proper herbicide treatment and use of a no-till drill, soil can be maintained. Sources agree on the importance of using the correct seed drill. The depth to which the seeds are planted is critical. Seeds of bluestem, Indian grass and others are light and fluffy and need to be set at a specific depth. A proper seed drill cuts through the layers of dead fescue, then plants a seed at the correct depth, and seals the trough over. Seed drills are available for use from Virginia Working Landscapes and VA Division of Forestry.
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TIMING Eradicating cool season plants must be done at the appropriate time of year. Most sources indicate fall as the best time to begin with a primary herbicide spray on cut vegetation, and a second spray in spring before planting. Some sources indicate fall planting can also work, but this needs to be timed with correct herbicide treatment.
As an alternative, the process can begin in spring with repeat sprayings of emerging plants into the fall, and then a late fall planting. Prairie Moon (2018a) provides a breakdown of the pros and cons to fall and spring plantings. If the mix is grassheavy, spring planting is better. If the mix is forb-heavy, fall planting is better.
Best practices for establishing a NWSG meadow (NRCS, VADGIF, UTK):
Five Reasons NWSG meadows fail, according to University of Tennessee (2004):
1. 2. 3. 4. 5. 6.
Mow in late summer; allow 6-10 inches regrowth. Herbicide (glyphosate) field. Allow 6-10 inches growth in spring; spray again. Burn or mow off dead vegetation. Spray weeds in summer when they reach 6-12 inches. Spot spray weeds once more in late summer with glyphosate (soil inactive). 7. Buy quality seed. Plant with a no-till seed drill in fall (with annual rye or other nurse crop) or spring at Âźinch depth with a properly calibrated drill. 8. Be patient. Very patient. 9. Mow weeds before they flower. 10. Repeat #8, then #9, then #8. It is possible in the scenario above to plant after step 4. However, attention will have to be given to weeds that emerge from the seed bank throughout the summer. Weeds in NWSG plantings should never be pulled.
1. Planted too deep: many grasses cannot be planted deeper than Âź inch. 2. Inadequate weed control: sod must be killed. 3. Planted too late: mid-April to early June is the window. 4. Drill not calibrated. 5. No patience. OSGF could experiment with variables to establishing NWSG in smaller plots. This could be a research initiative done in partnership with a regional university or agency. Because NWSG occur in a wide range of heights, the plants listed here tend to fall on the shorter side of the spectrum. The tallest plants, which are also some of the most common, are listed with asterisks. These plants should be considered for particular areas of the savanna such as along perimeters and buffers or lowlands where height can be used advantageously.
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GRASSLAND ZONING Following the species list below is a map outlining proposed management zones for Oak Spring’s open grasslands. Oak Spring’s ~120 acres of proposed grassland and savanna have been broken into 10 management zones based on pragmatic delineations such as roads and fences, and also soil conditions and topographic position. These management zones serve as plantings zones. Oak Spring can use one or two seed mixes in each zone. While there will be overlap in seed mixes, a wet-mesic zone should have a different mix than a dry-mesic zone. And for no other reason than beauty, diversity, and experimentation, zones with similar site conditions should also have different mixes. Because seed mixes are so easily customizable, Oak Spring should plan subtle differences in each mix for each zone such that different flora and fauna communities will develop, and so that people can experience different plants as they explore the landscape. With an average zone size of 12.3 acres, parcel sizes are manageable for planting. By planting two or three zones each year, the savanna will be completely planted within 3-5 years.
proportion of flowers than grasses. This section is proposed to be heavier on flowers, over grasses. The species list below is a useful starting place for composition; however, the mix should favor forbs over grasses. Most should be a short mix. However, tall species could be planted in the drainages. Seed companies offer a number of mixes for different site conditions and desired goals. Their websites are excellent resources for species mixes for specific site conditions, range maps for individual plants, and more.
PIEDMONT PRAIRIE NATURAL COMMUNITY Fleming et al. (2017) describe the small isolated Piedmont Prairie community found at Quantico Marine Base as dominated by little blue stem (Schizachyrium scoparium) and Indian grass (Sorgastrum nutans). Associates include purple false-foxglove (Agalinais purpurea), purple three-awn grass (Aristida purpurascens), bushy aster (Symphyotrichum dumosum), tick trefoils (Desmodium spp.), narrow leaf mountain mint (Pycnanthemum tenuifolium), papilose nutrush (Scleria pauciflora), and goldenrods (Solidago nemoralis and S. juncea). This species should be incorporated into a seed mix with the species listed below.
WILDFLOWER CENTERPIECE In the center of Oak Spring, between the Broodmare Barn, the Main House, and the Loughborough Barns, is 15 acres. It is proposed as a NWSG mixed meadow (or savanna if a few trees are added – being sure not to block views to the east), Typically, native meadows are planted with a higher
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LIST OF SPECIES FOR GRASSLANDS/SAVANNAS. This list was generated by pulling the most frequently used species from a number of lists including: Earnst Seed (2018), Prairie Moon (2018), University of Tennessee (2004), Virginia DIGF (2018), Virginia Working Landscapes (2018), Quin and Lapham (2013), Gibbens (2015), and Turner (2017). This list is not exhaustive; nor is it site specific to subtle nuances found at Oak Spring. It serves as a starting point to plan mixes for different areas.
Grasses
Forbs
Big bluestem (tall)
Andropogon gerardii
Partridge pea
Chamaecrista fasciculata
Broomsedge
Andropogon virginicus
Panicledleaf ticktrefoil
Desmodium paniculatum
Giant cane
Arundinaria gigantea
Rattlesnake master
Eryngium yuccifolium
Sideoats grama
Bouteloua curtipendula
Mistflower
Eupatorium coelestinum
Deer tongue
Dichanthelium clandestinum
Joe pye weed
Eupatorium fistulosum
Bottlebrush grass
Elymus hystrix
Maximilian sunflower
Helianthus maximiliani
Virginia wild rye
Elymus virginicus
Oxeye sunflower
Heliopsis helianthoides
Canada rush
Juncus canadensis
Scaly blazing star
Liatris squarrulosa
Beaked panicgrass
Panicum anceps
Blue lobelia
Lobelia siphilitica
Little blue stem
Schizachyrium scoparium
Spike lobelia
Lobelia spicata
Indian grass (tall)
Sorgastrum nutans
Wild bergamot
Monarda fistulosa
Purple top
Tridens flavus
Sensitive fern
Onoclea sensibilis
Eastern gamagrass
Tripsacum dactyloides
Tall white beardtongue
Penstemon digitalis
Narrowleaf mountainmint
Pycnanthemum tenuifolium
Forbs Nodding pink onion
Allium cernuum
Hoary mountainmint
Pycnathemum incanum
Common milkweed
Asclepias syriaca
Orange coneflower
Rudbeckia fulgida
Butterfly milkweed
Asclepias tuberosa
Browneyed Susan
Rudbeckia triloba
New England aster
Aster novae-angliae
Wild senna
Senna herbecarpa
Heath aster
Aster pilosus
Scented goldenrod
Solidago odora
Blue false indigo
Baptisia australis
Ohio spiderwort
Tradescantia ohioensis
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PROPOSED MANAGEMENT ZONES FOR GRASSLAND AND SAVANNA AREAS
Zone 1 2 3 4 5 6 7 8 9 10
Acres 10.9 10.4 13.4 7.6 26.2 8.1 10.1 15.8 8.3 12.7
Conditions dry-mesic mesic-wet wet-mesic mesic-wet dry-mesic dry-mesic dry mesic mesic-dry mesic-wet
Conditions are based on topographic position, and soil mapping by Jim Sawyer.
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As a final note, Dan Jones, Chairman and CEO for The
Parklands of Floyds Fork confirmed the fickle nature of NWSG: Meadows are difficult and will not perform, or act, as advertised! Act with caution and be ready for a different experience than you designed.
Grassland Resources Ernst Seed. 2018. Upland meadow seedmixes. https://www.ernstseed.com/product-category/uplands-meadows/ Fleming, G.P., K.D. Patterson, and K. Taverna. 2017. The Natural Communities of Virginia: a Classification of Ecological Community Groups and Community Types. Third approximation. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. http://www.dcr.virginia.gov/natural-heritage/natural-communities/ Gibbens, Wayne and Beth. 2017. Personal communication at Gibbensâ&#x20AC;&#x2122; Farm and written seed list on file at OSGF.
Quinn, S. and N. Lapham. 2013. The Farm at Sunnyside: 2013 Conservation Work Summary. http://thefarmatsunnyside.com/wpcontent/uploads/2016/07/2013-Conservation-Report.pdf Turner, T. 2017. NRCS Fauquier County, VA. Personal communication at Oak Spring. University of Tennessee Knoxville. 2004. A Landowners Guide to Native Warm Season Grasses in the Mid-South. UT Extension Office. http://utbfc.utk.edu/Content%20Folders/Forages/Forage%20Specie s/Publications/PB1746.pdf Virginia DIGF. 2018. Native Warm Season Grasses (NWSG): Establishment and Management. https://www.dgif.virginia.gov/quail/managing-your-land/old-fieldmanagement/nwsg/ Virginia Working Landscapes. 2018. Management Guides: Native Plants and Grassland Restoration. http://www.vaworkinglandscapes.org/resources/managementguides/40-native-plants-and-grassland-restoration
Prairie Moon Nursery. 2018a. Advantages and disadvantages to spring and fall planting. https://www.prairiemoon.com/blog/prosand-cons-to-fall-vs-spring-seeding? Prairie Moon Nursery. 2018. Seed mixes. https://www.prairiemoon.com/seed-mixes/
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Scattered Trees, Tree Clusters, and Shrub Islands In recent years scattered trees have been acknowledged as important ecosystem elements and keystone structures, while decreasing in abundance globally (Manning et al. 2006). The Midwest US, which had extensive oak savanna landscapes in presettlement times, has experienced a surge in interest and restoration of these landscapes over the past 10 years. Oak savannas took millennia to create, and they will take a long time to restore. As discussed in the Presettlement Landscape section in Part 1, Virginiaâ&#x20AC;&#x2122;s piedmont contained savanna vegetation in presettlement times. Though today the cultural land use practices that created the original savanna no longer exist (extensive burning), we can still recreate that important landscape type. Savanna is as valid as any other cover type. As noted, a savanna is a prairie-type landscape with scattered trees. Definitions range, however, on the density of tree cover. A commonly accepted version suggests at least one tree per acre (10%), and less than 50% canopy cover. With just over 100 acres of proposed savanna, Oak Spring will need to plant at least 100 trees in those areas to meet this goal. (Cover of 50% begins to resemble something more like woodland.) Nonetheless, with trees added to the native warm season plant mix a savanna is born.
Below is a table of tree species appropriate for planting as open-grown, scattered trees. Though one tree per acre may seem sparse, when those trees are large the landscape will appear filled in (a mature tree can have 1/10 of an acre canopy cover). For example, in the 25-acre Rock Meadow, the added complexity from 25 trees will increase dramatically (in time) to the otherwise open area. With the addition of clusters in some areas rather than a single tree, the Rock Meadow could easily hold 50-100 trees. A savanna is born. The tree species chosen below are known to be fire-adapted, open-grown trees elsewhere in the eastern US (Quercus alba, Q. velutina, Carya ovata, Q. marilandica, etc.), or they are known to grow in other open settings (Juniperus virginiana, Pinus echinata, Juglans nigra), or they are early successional and typically are found in younger open areas, often in clusters (Robinia pseudoacacia, Prunus serotina). Others are excellent for wildlife. The table lists site preferences for each species. Using the soil maps provided by Jim Sawyer to understand moisture conditions, species can be selected for their ability to tolerate dry conditions. Similarly, Sawyerâ&#x20AC;&#x2122;s maps detail granitic and basaltic (diabase) conditions, and these can be used for appropriate placement. However, because Oak Spring is such a mix of soils, species will likely do well on either rock type. Clustered trees are those that typically occur in groves in early successional situations.
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SITE PREFERENCES FOR SAVANNA TREES. The soil mapping conducted by Jim Sawyer provides a general sense of soil conditions and
should serve as reference in determining species locations. Common Name
Species Name
Dry site
Mesic site X
Granite
Diabase
Cluster
Eastern red cedar
Juniperus virginiana
X
Shortleaf pine
Pinus echinata
X
X
Pitch pine
Pinus rigida
X
X
Pignut hickory
Carya glabra
X
X
X
Shagbark hickory
Carya ovata
X
X
X
Mockernut hickory
Carya tomentosa
X
X
X
X
American chestnut
Castanea dentata
X
X
X
X
Eastern redbud
Cercis canadensis
X
X
X
Persimmon
Diospyros virginian
Black walnut
X
X
X
Single X
X
X
X
X
X X
X
X
X
X
Juglans nigra
X
X
X
X
Sweetgum
Liquidambar styracifla
X
X
X
Red mulberry
Morus rubra
X
X
X
X
Black cherry
Prunus serotina
X
X
X
X
White oak
Quercus alba
X
X
X
Southern red oak
Quercus falcata
X
X
X
X
Blackjack oak
Quercus marilandica
X
Chestnut oak
Quercus montana
X
X
Chinkapin oak
Quercus muehlenburgii
X
X
Northern red oak
Quercus rubra
Post oak
Quercus stellata
X
Black oak
Quercus velutina
X
Black locust
Robinia pseudoacacia
X
Sassafras
Sassafras albidum
X
X X X X
X
X
X
X X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
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Most of the trees listed are oaks and these are the most common, fire-adapted open grown species in all North American savannas. Midwest oak savannas are dominated by black oak and bur oak (out of VA range). The common open grown oak likely to have occurred in the northern Virginia Piedmont is white oak. Oak Spring has several presettlement white oaks, two of which are open grown. Thus, it’s suggested that white oak be planted as the dominant scattered tree in Oak Spring’s oak savannas. Several species listed here are not currently found at Oak Spring. These will add diversity to the site. Chestnut oak is found just across Goose Creek. Chinkapin oak is found in limestone-dominated savannas or woodlands and will likely do well on Oak Spring’s diabase. Blackjack oaks are extremely fire adapted, typically grow in stands, and occur in Fauquier County. Post oak, black oak, and shagbark hickory are rare at Oak Spring and should be planted widely. Southern red oak does not occur, but it is mentioned in the early settlement surveys (as Spanish oak). The pines are regional and will add color to the winter landscape.
trees should be very low density. Groves and clusters should be planted on north or east facing slopes, and in gullies. A grove should be planted in the drainage leading into the north side of the Lower Pond. SHRUB ISLANDS add yet more complexity, diversity, and beauty to the open savanna. Small shrub island thickets attract wildlife and break up the open savanna. The following shrub species (not exhaustive) can be used to create sunny shrub islands: SHRUBS SUITABLE FOR SAVANNA ISLANDS AT OAK SPRING Common Name Species Name Red chokeberry Aronia arbutifolia American hazelnut Corylus americana Fly honeysuckle Lonicera candensis American plum Prunus americana Chickasaw plum Prunus angustifolia Smooth sumac Rhus glabra Prairie willow Salix humilis Viburnums Viburnum spp.
American chestnut would have occurred on the site 100 years ago before the blight. It is suggested that OSGF form a partnership with The American Chestnut Foundation and plant two chestnut clusters (orchards) in the savannas. In general, tree densities should follow topographic cues. For example, on drier ridge-tops, or south and west facing slopes,
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Scattered Tree Resources Manning, A., J. Fisher, D. Lindenmayer. 2006. Scattered trees are keystone structures â&#x20AC;&#x201C; implications for conservation. Biological Conservation 132: 311-321. Natural Resource Conservation Service. 2003. Designing an Oak Savanna. Conservation Practice Information Sheet: Savanna Information Sheet (IS-MO643). https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs144p2_ 010804.pdf Savanna Oak Foundation, Inc. 2018. Oak Savannas. http://www.oaksavannas.org/ [Accessed January 12, 2018]. Tulip poplar Liriodendron tulipifera
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Reforestation This plan suggests reforestation of ~40 acres of current fescue hayfield. The purposes for reforestation include: larger forest block size to support interior species; increased forest plant diversity; wildlife habitat creation; carbon sequestration; and reduced maintenance costs (and carbon emissions) over time by the elimination of mowing. Ideally, reforestation would occur on restored native warm season grass and forb communities. This is preferred over planting trees in existing fescue-dominated hayfields for several reasons. First, it establishes a native base layer that serves as a functioning community during the interim (15 years) until the trees establish canopy closure. Second, if planted with the correct mix of semi-shade tolerant species, the herbaceous base layer will become an appropriate native understory layer when trees reach canopy height. Third, establishing a new ground cover after the trees are established will add complexity to the process, cost, and increased risk of damage or mortality, to the new trees. Nonetheless, planting trees on a NWSG base means waiting 13 years before tree planting. The effort and patience can have long-term rewards from increased native diversity in the understory to reduced management costs for the elimination of exotics later.
A map below outlines nine reforestation zones ranging from 2 to 8 acres in size. Zones are based on pragmatic aspects for planting (e.g. fence lines, size, etc.), and soil mapping by Jim Sawyer with primary consideration given to depth to bedrock, soil moisture, and topographic position. The Soil section in Part 2 provides all of Sawyerâ&#x20AC;&#x2122;s maps, including one showing Hardwood Productivity. This map layer was considered primarily in determining these zones. The zones are defined on the map as some combination of dry (xeric), mesic, or moist. These categories should be taken broadly as zones contain many soil units of broad-spectrum conditions. The important aspects are the extremes; the very moist and very dry soils should be planted appropriately. A species list follows that indicates which species are suitable for which site conditions. Zones 1, 2, and 3 comprise the largest planting area at 13 acres. Sawyerâ&#x20AC;&#x2122;s maps consider zone 1 as having high potential for hardwood productivity. Zone 2 is moderate productivity and zone 3 is low on account of shallow soils, and ridge location. This is the poorest zone and should be planted with very dry-adapted species. Zone 2a is proposed inside zone 2 as a ž-acre of conifer planting of white pine and shortleaf pine. The purpose of this conifer stand is to offer winter roost habitat for birds and other animals. Pines should continue to the edge in zone 1 to offer edge connectivity and hunting opportunity.
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Zone 4 is the Goose Creek bottomland. Reforesting this area is the best thing Oak Spring can do for water quality on Goose Creek. In addition to trees, (especially sycamore which are uncharacteristically sparse at OSG), river cane (Arundinaria sp.) should be planted widely. The species was common throughout the east but has been cleared and grazed to regional extirpation. Its current range marginally includes northern Virginia. Zones 5 and 6 comprise steeper slopes along the southern property border. Zone 6 was planted in 2017 on fescue with a fast-growth mix comprising nearly 2000 trees in an effort to screen the neighboring home. Zone 5 is more mesic according to soil maps. Some fast-growing pines and broadleaf trees are suggested here to build a visual screen. On the east side of Wild Pond, zone 7 contains a mix of soil types and conditions, likely a result of earth-moving during the original pond construction. Dry-sited species will be best here, with some mesic types closer to the pond and on suitable soils. The trees may stay short as a consequence of poorer soils, however, shorter trees could be used here to prevent visual barriers in what is the center of Oak Spring. Zone 8 is considered high and moderately high for hardwood productivity. Mesic species should be planted here with conifers mixed in to provide screening, perhaps on the north edge so as to visually frame the hardwoods in front.
Finally, zone 9 contains a small inner strip connecting zones 1 and 8 and a perimeter strip. The grassland in the middle was kept because of it’s views and open rock outcrops that make better fauna habitat in an open setting (warm sun) than in a shaded forest. The zone could be planted as wide, scattered trees. The south end of this zone has wet soils (seasonally standing water), which could retain interesting species. The northern reach is on a ridge with shallow soils and will require more xeric species. Following the 2017 planting of Zone 6, the next priority zone could include Goose Creek bottomland (zone 4). This area is high priority due to the benefits to water quality. Next level priorities might be zones 2, 3, and 1, after a low height crop of native warm season grasses and forbs are installed.
NATURAL COMMUNITIES APPROACH Part 2 described Oak Spring’s natural communities as Basic Oak Hickory Forest and Piedmont Small Stream Alluvial Forest (Fleming et al. 2017). Two additional communities should be considered likely occurrences prior to land clearing in settlement times and possible reference communities for reforestation efforts. These include Mountain/Piedmont Basic Woodlands, and Oak–Hickory Woodlands and Savannas (Fleming et al. 2017). These community types may serve as suitable benchmarks and analogs for restoration of Oak Spring uplands.
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PROPOSED REFORESTATION ZONES AT OAK SPRING
Zone
Acres
Conditions
1 2 2a 3 4 5 6 7 8 9
6.7 3.8 0.7 2.2 5.1 3.5 2.2 3.1 8.6 3.0
mesic dry-mesic dry-mesic dry moist mesic-dry dry-mesic dry-mesic mesic dry-moist
Zone 2a is recommended as a small pine stand. See text. Conditions refer to general soil conditions with regard to moisture retention, depth to bedrock, and topographic position taken from Jim Sawyerâ&#x20AC;&#x2122;s soil survey. See the Soil section in Part 2.
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MOUNTAIN / PIEDMONT BASIC WOODLANDS occur on dry sites composed of diabase (Oak Spring), gabbro, or metabasalt. Sites tend to be dry, rocky, especially on south-facing slopes. White ash (Fraxinus americana), is often dominant, however, the species is uncommon at Oak Spring and failing due to emerald ash borer. Other dominants include hickories (Carya spp.), oaks, eastern red cedar (Juniperus viginiana), eastern red bud (Cercis canadensis), hophornbeam (Ostrya virginiana), ninebark (Physocarpus opulifolius), hackberries (Celtis spp.), and a number of graminoids and forbs (Fleming et al. 2017). OAK HICKORY WOODLANDS AND SAVANNAS are currently rare in Virginia supported only at military bases subjected to periodic fire. Communities tend to grow on acidic soils, but occasionally occur on diabase. Where they do occur on diabase, communities are more forb-dominated. Dominants include white oak (Quercus alba), black oak (Q. velutina), southern red oak (Q. falcate), Post oak (Q. stellata), and hickories (Carya spp.). Understory shrub layers tend to be sparse. Herbaceous layers are dense, and include little blue stem (Schizachyrium scoparium) Indian grasses (Sorgastrum nutans), and broomsedges (Andropogon spp.). Forbs include nitrogen-fixing legumes such as hog peanut (Amphicarpea bracteata) and tick-trefoils (Desmodium spp.) as well as goldenrod (Solidago spp.), colonies of nettle-leaf sage (Salvia urticifolia), and sunflowers (Helianthus spp.) (Fleming et al. 2017).
SPECIES LISTS Currently, Oak Spring contains 45 native woody plant species. Several of these species include only a single individual on the property (e.g. white pine, American beech, witch hazel, etc.). Adjacent properties contain additional species that do not occur at Oak Spring such as chestnut oak and black birch. With reforestation, the woody plant diversity at Oak Spring could roughly double. One hundred species of native woody plants could be a goal. This species recommendations is divided into three lists: • • •
Moist bottomland of Goose Creek and Spring Branch Mesic sites (moderate) in mid-slope areas Somewhat xeric to mesic-xeric sites (drier)
Rather than a complete species list of everything that could be found at these sites, the list provided is a planting list. It skips species that are already common (e.g. box elder in the bottomland) or those facing imminent extirpation (e.g. ash). Each species is given a number 1 to 5 to suggest relative abundance in plantings, with higher numbers indicating dominants and lower numbers indicating sparsely planted species. The lists include only trees and some shrubs. Shade tolerant herbaceous flora should be added once canopy closure is reached. However, some appropriate herbs could be included in the establishment of NWSG prior to tree planting.
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BOTTOMLAND SPECIES LIST FOR REFORESTATION. This list includes trees and shrubs only. Imp refers to importance value, with higher number species being planted more frequently as dominants. Com m on Nam e Species Nam e Im p Com m on Nam e Species Nam e Im p Red maple
Acer rubrum
3
Cucumbertree
Magnolia acuminata
1
Silver maple
Acer sacharinium
2
Sweetbay magnolia
Magnolia viginiana
1
Serviceberry
Amalanchier sp.
1
Red mulberry
Morus rubra
2
Red chokecherry
Aronia arbutifolia
2
Black gum
Nyssa sylvatica
2
River cane
Arundinaria sp.
3
White pine
Pinus strobus
2
Pawpaw
Asimina triloba
2
Sycamore
Platanus occidentalis
5
Black birch
Betula lenta
2
Eastern cottonwood
Populus deltoides
2
River birch
Betula nigra
3
Swamp white oak
Quercus bicolor
4
Musclewood
Carpinus caroliniana
3
Pin oak
Quercus palustris
4
Bitternut hickory
Carya cordiformes
2
Willow oak
Quercus phellos
2
Shagbark hickory
Carya ovata
3
Shumard oak
Quercus shumardii
2
Hackberry
Celtis occidentalis
3
Common elderberry
Sambucus canadensis
2
Redbud
Cercis candensis
3
Bald-cypress
Taxodium distichum
1
Sweet pepperbush
Clethra alnifolia
3
American basswood
Tilia americana
3
Dogwood
Cornus florida
3
American elm
Ulmus americana
3
Persimmon
Diospyros virginiana
2
Slippery elm
Ulmus rubra
3
Black walnut
Juglans nigra
2
Highbush blueberry
Vaccinium corymbosus
2
Sweetgum
Liquidambar styraciflua
4
Southern arrowwood
Viburnum dentatum
1
Tulip poplar
Liriodendron tulipifera
3
Southern wild raisin
Viburnum nudum
1
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MESIC SITE SPECIES FOR UPLAND REFORESTATION PLANTINGS. This list includes only trees and shrubs. Imp refers to importance value and indicates relative abundance of each species for plantings. Higher numbers indicate higher dominance. Com m on Nam e Species Nam e Im p Com m on Nam e Species Name Im p Sugar maple
Acer saccharum
1
Sweetgum
Liquidambar styraciflua
2
Serviceberry
Amelanchier sp.
2
Tulip poplar
Liriodendron tulipifera
4
Pawpaw
Asimina triloba
2
Cucumbertree
Magnolia acuminata
1
Black birch
Betula lenta
3
Southern magnolia
Magnolia grandiflora
1
Bitternut hickory
Carya cordiformes
3
Black gum
Nyssa sylvatica
2
Pignut hickory
Carya glabra
3
Hophornbeam
Ostrya virginiana
2
Shagbark hickory
Carya ovata
2
Sourwood
Oxydendrum arboreum
1
Mockernut hickory
Carya tomentosa
2
Shortleaf pine
Pinus echinata
1
Hackberry
Celtis occidentalis
3
Eastern white pine
Pinus strobus
1
Eastern redbud
Cercis candensis
2
Black cherry
Prunus serotina
3
Flowering dogwood
Cornus florida
3
White oak
Quercus alba
4
American hazelnut
Corylus americana
1
Southern red oak
Quercus falcata
3
Persimmon
Diospyros virginiana
2
Chestnut oak
Quercus montana
2
Honeylocust
Gleditsia triacanthos
1
Northern Red oak
Quercus rubra
2
Witch hazel
Hamamelis virginiana
3
Post oak
Quercus stellata
4
American holly
Ilex opaca
3
Black locust
Robinia pseudoacacia
2
Black walnut
Juglans nigra
2
Raspberry
Rubus spp.
2
Eastern red cedar
Juniperus virginiana
2
Elderberry
Sambucus sp.
1
Mountain laurel
Kalmia latifolia
1
Sassafras
Sassafras albidum
1
Spicebush
Lindera benzoin
2
Viburnum sp.
Viburnum sp.
2
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DRY SITE SPECIES LIST FOR REFORESTATION PLANTINGS. This list includes only trees and shrubs. Dry sites inherently have lower diversity and abundance than moist sites. Imp refers to Importance value (1-5) and is a relative proportion of trees planted. Higher number suggests planting with higher frequency in the mix. Com m on Nam e Species Nam e Im p Com m on Nam e Species Nam e Im p Canada serviceberry
Amelanchier canadensis
1
Shortleaf pine
Pinus echinata
2
Sweet birch
Betula lenta
1
Eastern white pine
Pinus strobus
2
Pignut hickory
Carya glabra
4
Virginia pine
Pinus virginiana
1
Shagbark hickory
Carya ovata
3
Black cherry
Prunus serotina
2
Mockernut hickory
Carya tomentosa
4
White oak
Quercus alba
4
Allegheny chinkapin
Castanea pumila
1
Scarlet oak
Quercus conccinea
3
Eastern redbud
Cercis candensis
3
Southern red oak
Quercus falcata
4
Flowering dogwood
Cornus florida
2
Chestnut oak
Quercus montana
3
Persimmon
Diospyros virginiaia
2
Northern red oak
Quercus rubra
2
Common juniper
Juniperus communis
2
Post oak
Quercus stellata
3
Eastern red cedar
Juniperus virginiana
3
Black oak
Quercus velutina
4
Sweetgum
Liquidambar styraciflua
2
Winged sumac
Rhus copallinum
2
Tulip poplar
Liriodendron tulipifera
2
Smooth sumac
Rhus glabra
3
Blackgum
Nyssa sylvatica
2
Sassafrass
Sassafras albidum
3
Hophornbeam
Ostrya virginiana
3
Winged elm
Ulmus alata
3
Reforestation Resources Fleming, G.P., K.D. Patterson, and K. Taverna. 2017. The Natural Communities of Virginia: a Classification of Ecological Community Groups and Community Types. Third approximation. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. http://www.dcr.virginia.gov/natural-heritage/natural-communities/
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Wetlands/Pond Margins The Loughborough Spring and the run below it are the main ‘wetland’ elements at Oak Spring. Spring Branch, below the springhouse, is also a perennial seepage run. The species list here can serve as a base for both areas; however, Spring Branch should likely be planted more formally. Pond margins should be planted for bank stabilization, goose control, and aesthetics. This list serves those areas also. The Loughborough Springs area could be called the Wetland Garden to continue a theme with the Woodland Garden.
In doing so, attention to which areas will be shrub thickets and which will be open herbaceous will depend on the extent of hydric soils and saturated conditions, as well as the way people will view and interact with the site. This should be determined on the ground. The list provided here includes suggestions for the 80-90% vegetation on these sites. These species are the dominants one would expect to find in a natural community. Additional species to plant in these sites can be gathered from listed resources.
In presettlement times, it is likely that the Loughborough Spring (and run) would have been under a tree canopy. As a seepage (spring) wetland in a forest, the site may have been vegetationally somewhat unremarkable: Vaccinium sp., Ilex, and other shrubs, or open shallow water with marginal herbaceous vegetation such as skunk cabbage (Symplocarpus foetidus). In full-sun, as it occurs now, however, recreating that unknown community isn’t possible. A more diverse community is more suitable for the site and offers a huge botanical opportunity. In this environment, the site could be shaped as a scrub-shrub seepage wetland. The goal should be to create a diverse area, composed of native species with complex structure, that functions as a spring head/run and reflects Oak Spring’s approach to vegetation. The site presents a great opportunity to create a functional showpiece.
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LIST OF SPECIES FOR SEEPAGE WETLAND, SPRING RUN, AND POND MARGINS. This list is not exhaustive; see reference links for additional species suggestions. Trees Herbaceous Forbs, Graminoids, Ferns Swamp white oak
Quercus bicolor
Sweetflag
Acorus calmus
Black gum
Nyssa sylvatica
Marsh marigold
Caltha palustris
Black willow
Salix nigra
Tussock sedge
Carex stricta
Bald cypress
Taxodium distichum
Sensitive fern
Onoclea sensibilis
White turtle-head
Chelone glabra
Shrubs Smooth alder
Alnus serrulata
Compact dodder
Cuscuta compacta
Buttonbush
Cephalanthus occidentalis
Spike rush spp.
Eleocharis spp.
Sweet pepperbush
Clethra alnifolia
Joe pye weed
Eupatorium fistulosum
Silky dogwood
Cornus amomum
Virginia blue flag
Iris virginica
Smooth winterberry
Ilex laevigata
Virginia sweetspire
Itea virginica
Winterberry holly
Ilex verticillata
Turkâ&#x20AC;&#x2122;s cap lily
Lilium superbum
Spicebush
Lindera benzoin
Cardinal flower
Lobelia cardinalis
Swamp azalea
Rhododendron viscosum
Water purslane
Ludwigia palustris
Swamp rose
Rosa palustris
Cinnamon fern
Osmunda cinnamomea
Silky willow
Salix sericea
Pickerel weed
Pontederia cordata
Elderberry
Sambucus canadensis
Broad leaf arrowhead
Sagittaria latifolia
Common greenbrier
Smilax rotundifolia
Lizardâ&#x20AC;&#x2122;s tail
Saururus cernuus
Highbush blueberry
Vaccinium corymbosum
Green bulrush
Scirpus atrovirens
Southern arrowwood
Vibernum dentatum
Marsh fern
Thelypteris palustris
Southern wild raisin
Viburnum nudum
Cattails
Typha spp.
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Wetland Resources
Forest Understory
Virginia Department of Conservation and Recreation. Native Plants for Conservation, Restoration, and Landscaping: Virginia Riparian Buffer Zones. http://www.dcr.virginia.gov/naturalheritage/document/riparian-nat-plants.pdf
Oak Springâ&#x20AC;&#x2122;s forests, on the slopes above Goose Creek and in the Young Woods beyond it, are composed of a tree canopy layer (old growth and successional) and an invasive, exotic dominated ground layer. While there are scattered tree seedlings and occasional mature shrubs, on the whole, the woods lack tree-regeneration and a shrub layer. While elements of native herbaceous plants occur, the herbaceous flora is dominated by exotic vegetation. Two centuries of land use including woodland grazing have eliminated the lower woody layers from the old growth section. Overabundant deer in recent decades have prevented regeneration in both the old growth and young woods.
Virginia Department of Conservation and Recreation. Piedmont Seepage Swamp Virginia. http://www.dcr.virginia.gov/naturalheritage/natural-communities/ncpc3 Piedmont Environmental Council. Common Wetland Plants of Northern Virginiaâ&#x20AC;&#x2122;s Piedmont: A Field Guide. https://www.pecva.org/library/documents/ResourcesPublications/Publications/Plant-Wildlife/WetlandPlantGuide.pdf
The exotic plant plan calls for additional shrubs to be planted in an effort not only to add diversity and structure to the woods, but also to create shade for preventing future exotic plant infestations. The species offered below present a comprehensive list for understory additions in the forest. A partial list for herbaceous plants is provided, as a dense ground cover will counter exotic infestation. Included in the list are plants known to spread vegetatively. As overabundant deer remain an issue, seedlings of palatable species will need to be planted and protected for a forest of the future.
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LIST OF UNDERSTORY SPECIES ADDITIONS FOR THE FORESTS. Some species already occur in the forest in small numbers. This list mostly reflects a Basic Oak-Hickory Forest classification. However, granite does outcrop in the forests so a few acidic-sited species are listed. Some experimentation with plantings may yield interesting results. Most species here are relatively resistant to deer, however, precautions should be taken during establishment. Species with a preference for part sun should be planted in the large gaps of fallen trees.
Forbs, Gram inoids, Ferns
Understory Trees Serviceberry
Amelanchier sp.
Maidenhair fern
Adiantum pedatum
Eastern redbud
Cercis canadensis
Wild leeks / Ramps
Allium tricoccum
Flowering dogwood
Cornus florida
Wild sarsaparilla
Aralia nudicaulis
Hop hornbeam
Ostrya virginiana
Goatsbeard
Aruncus dioicus
Cane
Arundinaria teca
Shrubs Devil’s walking stick
Aralia spinosa
Bearded shorthusk
Brachyelytrum erectum
Pawpaw
Asimina triloba
Woodland sedge
Carex pensylvanica
Allegheny chinkapin
Castanea pumila
Plantain-leaved sedge
Carex plantaginea
Alternate leaved dogwood
Cornus alternifolia
River oats
Chasmanthium latifolium
Leatherwood
Dirca palustris
Wild comfrey
Cynoglossum viginianum
American strawberry-bush
Euonymus americanus
Intermediate wood fern
Dryopteris intermedia
American holly
Ilex opaca
Solomon’s plume
Maianthemum racemosum
Spicebush
Lindera benzoin
Virginia bluebells
Mertensia virginica
Ninebark
Physocarpus opulifolius
Rock muhly
Muhlenburgia sobolifera
Witch hazel
Hamamelis viginiana
Mayapple
Podophyllum peltatum
Elderberry
Sambucus canadensis
Solomon’s seal
Polygonatum biflorum
Bladdernut
Staphlea trifolia
Virginia spiderwort
Tradescantia virginiana
Blackhaw viburnum
Viburnum prunifolium
American wisteria
Wisteria frutescens
Wild raisin
Viburnum nudum
Mapleleaf viburnum
Viburnum acerifolium
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Forest Understory Resources Plant NoVA Natives. 2017. Native Plants for Northern Virginia. http://www.plantnovanatives.org/ [Accessed: 12, January 2018] Virginia Department of Conservation and Recreation. 2011. Native Plants for Conservation, Restoration, and Landscaping: Virginia Piedmont Region. http://www.dcr.virginia.gov/natural-heritage/document/pied-natplants.pdf [Accessed: 12, January 2018] Fleming, G.P., K.D. Patterson, and K. Taverna. 2017. The Natural Communities of Virginia: a Classification of Ecological Community Groups and Community Types. Third approximation. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. http://www.dcr.virginia.gov/natural-heritage/natural-communities/ [Accessed: 12, January 2018]
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Woodland Garden The proposed Woodland Garden area comprises approximately one acre. It offers a remarkably diverse landscape packed into a small area: a section of Spring Branch including a small bedrock waterfall; rich moist alluvial flat areas, dry rocky slopes; presettlement oaks; proximity to the main residence.
should be arranged in ways to create an immersive experience. This will require thoughtful and intricate design. Because of the huge breadth of species options possible for a Woodland Garden, a list is not provided. The resources listed in this section provide a wide range of native species.
Because of this concentration of features in a small area, the site is ideal for concentrated plantings and use. After cleaning out the exotics native plantings, and non-spreading exotics, can shape the area into a unique experience. Trails and sitting areas can provide access, enjoyment, and a quiet reflective space for Oak Spring guests. (If Oak Spring ever took on an acquisition of more property, the remaining wooded â&#x20AC;&#x153;triangleâ&#x20AC;? to the south of this space would make for an excellent addition. It would expand the woodland garden options considerably. Without acquisition, perhaps OSG can reach a management agreement with neighbors to clean exotics out of this small area.) Unlike the forest, where the goal of understory plantings should be to gain broad and continuous ground cover with naturally spreading native plants, on this site, a less common, showy, suite of plants can be planted to highlight the variability of the site. Interesting ephemerals, rare or uncommon forest perennials, ferns, bryophytes, and more
THE PROPOSED WOODLAND GARDEN area is shown in green. Spring Branch flows through from north to east. The wooded triangle to the south could make a good acquisition or management agreement with the neighbors.
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Green Screens
•
During the Mellon era, the core property that is today Oak Spring had no neighbors. With division of Rokeby farms, Oak Spring now shares property boundaries with three neighbors.
• •
The height of the plantings over time and how much sun or other views they will block Amount of time the plantings will need to achieve functionality (privacy) Ability of the screen plants to self propagate (to be avoided)
In an effort to increase privacy at Oak Spring (and increase privacy for the neighbors), a few areas should have tall evergreen “screens” planted. For example, a green screen on the lower section of Peach Tree Lane will shield the views one currently sees toward the Brick House on the drive in. It will also shield those residents from headlights and noise created by this entry. The primary areas for screening lie to the west and south of the residence. Screening the western half of Peach Tree Lane should be avoided, as there are a number of views to the Broken Hills and Blue Ridge. The map outlines locations for needed screens. A variety of plants can be used: giant arborvitae, holly, spruce, and many others. A combination of species would create a screen that is beautiful as it is functional. Someone with knowledge of ornamentals and an eye for arrangement should take up the planting plan. Considerations for the Green Screen include: • Evergreen or deciduous plantings • Preserving visibility of the stonewall south of the main residence
PROPOSED GREEN SCREENS are shown in green. The new driveway is shown in gray. Some screen areas are narrow. The section due south of the residence has a stonewall on the border.
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Potential Agriculture
Formal / Ornamental
The four agricultural areas total 10.5 acres. The sites were identified based on i) the soils survey completed by Fauquier County soil scientist Jim Sawyer (maps in Part 2) and ii) proximity to OSG infrastructure such as power, water, barns, etc. If these areas are not put into agriculture, the three northern fields can be included in the savanna or grassland cover types that surround them. The southern section is close to the Main House and Library and could be planted into additional formal/ornamental or some other creative design.
These two sections occur in high-use areas, or already contain some degree of formal arrangement. The south section includes finish-cut mowed areas near the cemetery, ponds, and residence. Apple trees, and other open-grown trees dot the area. While this area may not change, it will be finish-cut mowed and could use additional design elements. The area near the Broodmare Barn is the hub between that place, the Library, and the Main House. This area will want a design to capture peoplesâ&#x20AC;&#x2122; attention walking between these primary buildings. An integrated path should be in the design.
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other birds to hunt and rest in Oak Spring’s open areas.
W ATCHABLE W ILDLIFE Part 2 of this document provided an inventory of observed wildlife at Oak Spring. It’s recommended that Oak Spring follow up on the inventory of fauna on the property. Inventory should include insects and other invertebrates, reptiles and amphibians, aquatic organisms in the ponds and Goose Creek, and small mammals. An interesting study could be done comparing taxa before and after restoration. The Fauna section in Part 2 details a number of strategies for increasing wildlife abundance and, as an extension, viewing fauna by people. Creating habitat complexity, adding plant species richness, and placing artificial nest boxes and platforms will increase watchable wildlife at Oak Spring. Habitat complexity and diversity has been addressed in the above vegetation plan (reforestation, savanna, scattered trees, shrub islands). To summarize the additional features detailed in the Fauna section in Part 2: •
NEST BOXES: Populations and visibility of kestrel, bluebird, owls, and bats (among others) can all be increased with installation of nest boxes.
•
NEST PLATFORMS: Two locations for raptor platforms to attract Osprey have been identified.
•
RAPTOR POLES/PERCHES: Perches in the open areas, especially the Rock Meadow, will permit raptors and
•
ROCKS, LOGS, AND FLOATING MATS: Features on the margins of ponds and in the ponds themselves will facilitate turtles and other aquatic animals in the ponds. Eliminating fish from the smaller ponds will increase populations of prey species.
•
SCATTERED TREES: These keystone structures have been discussed above.
•
SHRUB ISLANDS: Patches of shrubs in the open savanna areas can create excellent habitat for fauna. Species mix is above.
•
CONIFER GROVE: A patch of conifers or clusters of conifers offer excellent habitat to owls and other birds especially in winter where they roost on cold nights. A patch is proposed in the reforestation area.
See the Fauna section in Part 2 for additional details and references. A Wildlife Plan could be developed to detail locations for artificial features.
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T RAIL S YSTEM Oak Spring will house guests from all over the world. With a proper map and wayfinding, they can experience the richness of the site’s special places and rich landscape described in this report. To do that, Oak Spring needs a trail system. The trails themselves can be constructed in any manner, as long as they are well marked. The trails closer to the residence and other buildings, and formal areas, should have an appropriate surface and clear markings. Trails in the outer reaches may offer little more than a mown path. Trails should be sustainable – that is, they should avoid steep slopes, fall line grades, and grades over 10-15%. A good trail plan: • •
• •
Connects a series of special places, some natural and some built. Considers the user’s experience of the landscape with regard to at-hand features, distant views, sounds, seasonality, diversity, and difficulty. Considers amenities such as places to rest, shade, remote meeting spots, etc. Is designed for sustainability with regard to slopes, soils, erosion, surface, and ecology.
This trail plan for Oak Spring is designed with these considerations. The system totals 5.4 miles and takes in most of the property’s sweet spots. Some of the trails are already in place as old farm paths. Some should be constructed as natural surface trails, and others should have crushed fine material. On steep slopes in the woods, a simple bench-cut grade should be made. The map below details the trail system. The vegetation plan is included such that one can see how the landscape interacts. Stars locate distant mountain views; a rest spot with a shade tree and bench or chairs should be installed in these locations. The trail system should invite relaxation; it should encourage people to stop and smell the flowers. For perspective, a loop around the perimeter trails from the Broodmare Barn totals 3.35 miles (5.4km). Trails have been planned to connect key locations including the Loughborough Barns, Memory House, Broodmare Barn, and Main Residence, as well as ponds, significant trees and Special Places. Of the 20 Special Places, only the Loughborough Springs do not occur on the trail network. On the ground, trails should be laid out with three objectives: i) offering a diverse trail experience; ii) directing the users eye toward views and features; iii) keeping grades appropriate to prevent erosion and maintain access for everyone.
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PROPOSED TRAIL SYSTEM AT OAK SPRING Total distance for all trails is 5.4 miles. A walk on the perimeter totals 3.35 miles. Stars indicate locations with views (subject of view is labeled). Colors show proposed vegetation cover from the vegetation plan above.
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THE MISSION OF THE OAK SPRING GARDEN FOUNDATION is to perpetuate and share the gifts of Rachel (â&#x20AC;&#x153;Bunnyâ&#x20AC;?) Lambert Mellon, including her residence, garden, estate and the Oak Spring Garden Library, to serve the public interest. Oak Spring is dedicated to inspiring and facilitating scholarship and public dialogue on the history and future of plants, including the culture of gardens and landscapes and the importance of plants for human well-being.