WOODLAND HEALTH Stewardship Options for
Iowa Woodland Owners
May 2004
WOODLAND HEALTH Stewardship Options for Iowa Woodland Owners
INTRODUCTION A GLANCE AT IOWA WOODLANDS History and Current Status of Iowa Woodlands ........ 6 Value of Iowa Woodlands ....................................... 8 Getting to Know Your Woodland ........................ 10
SOME STEWARDSHIP OPTIONS Recognizing and Controlling Invasive Plants .............12 Filling in the Gaps ...................................................20 Limiting Damage from Livestock and Deer ...........22 Avoiding Further Fragmentation of Woodlands .........23 Permanently Protecting Your Woodland ...............25
IF YOU WANT TO KNOW OR DO MORE Resources .................................................................28
Our thanks to the Roy J. Carver Charitable Trust of Muscatine, Iowa, for partially funding production of this booklet. Our thanks, as well, to Cheri Grauer, INHF staff, for research and writing; to Larry A. Stone, who provided both peer review and editorial assistance; to Heather Von Arb, INHF intern, for her design assistance; and to Mark Muller, Down to Earth Graphics, for the use of his woodland illustrations. 2
WOODLAND HEALTH
For twenty-five years, the Iowa Natural Heritage Foundation has assisted landowners in protecting natural areas—woodlands, wetlands, and prairies— and the wildlife that inhabit those wild places. As we’ve met and worked with Iowa woodland owners, we’ve discovered that, although there is a wealth of information available to them about managing forests for timber production, there is little that focuses primarily on managing woodlands to maintain or improve their overall health and diversity. Several natural resource professionals agree with that assessment, among them: • Don Farrar, Department of Ecology, Evolution and Organismal Biology, Iowa State University; • Heidi Abjornson, Department of Natural Resource Ecology and Management, Iowa State University; • Jean Eells and Del Christensen, Prairie Rivers of Iowa RC&D; • Paul Tauke, Iowa Department of Natural Resources; • Mark Pingenot, Trees Forever. Our thanks to these individuals for their contributions to, and their comments on, this preliminary management guide. We will continue to work together to identify additional research needs and management tools that will contribute to the enhanced health of Iowa forests. This booklet brings together an array of information on several issues related to woodland health. It both introduces the topic and suggests a few stewardship options to promote health. INTRODUCTION
3
Woodlands—on hearing the word, many of us are transported back to a particular time and place of childhood. Your woodland might have covered the rolling hills of a small corner of southern Iowa with spreading oaks and towering hickories. Or it might have been a stand of wild plums and hawthorns in the heart of town, stretching over what would later become four or five house lots. Regardless of the kind of woodland, it was magical. When you stepped off the bluegrass lawn and into the woods on a spring day, you crossed over to another world. The soft green was easy on the eye and the still, moist air felt like a kiss. Birdsong filled your ears and the perfume of plum blossoms tickled your nose. Dew-spangled trout lily, Dutchman’s breeches, wood violet, and columbine spread underfoot in clumps of white, purple, and red. Gray squirrels scolded you while they scampered from treetop to treetop. Cottontail rabbits exploded from the gooseberries at the sound of your footstep. As children, we knew that woodlands provided solace on some days and a playground on others. We knew the woods to be home to myriad other-than-human creatures. We also knew them to be spots of singular beauty. In other words, woodlands were a place set apart from other places. . . and so for many of us they remain. This booklet introduces the topic of woodland health and is directed at those who own woodlands to enjoy their beauty and tranquility, to protect nature and biological diversity, and to conserve wildlife habitat. It is especially aimed at those for whom woodland ownership evokes a stewardship response.
4
WOODLAND HEALTH
This is not a comprehensive management guide. Rather, we offer a few stewardship options for a handful of the most commonly faced management issues: invasive plants, deer and livestock damage, and habitat fragmentation among them. Addressing these issues can be a first step to the return of woodland health. NOTE: This guide does not discuss savanna or savanna management. Savanna is an important, threatened ecosystem, composed of a mixture of woodland and prairie vegetation. If your woodland is rather open, features lowlimbed, spreading oaks with a grassy or brushy ground cover, or has a scattering of prairie plants, it may be a savanna. Contact your district forester or your county conservation board for information and assistance. This guide does not address management from a timber production perspective. An abundance of information on this topic is available from the Iowa Department of Natural Resources, Iowa State University Extension, and other sources. Please see resources at the back of this booklet.
INTRODUCTION
5
A GLANCE AT IOWA WOODLANDS
History and Current Status of Iowa Woodlands The present Iowa landscape reflects its geologic, climatic, and cultural past. Most of the table-top flat to rolling land that now features a repeating pattern of corn and bean fields once was blanketed in prairie. Notable exceptions were major stream and river valleys and the northeast corner of the state, where forests—or woodlands—predominated. As the last ice sheets were retreating, about 14,000 years ago, spruce, fir, and pine trees probably were the dominant forest species. Within 5,000 years and with the climatic change that occurred in the wake of the melting ice, the trees that are now locally familiar to us—oak, elm, maple, and basswood— assumed a dominant role on the landscape. Warmer, drier conditions and the prevalence of fire may have limited woodlands to the more hospitable—cooler and damper—habitats along major streams and rivers. Similarly, the Driftless Area, a portion of northeast Iowa that was all but untouched by the last glaciation, was marked by a cooler, more moist climate and extensive forests. Bohumil Shimek, an early professor of natural sciences at the University of Iowa and a lifelong naturalist, surmised that at the beginning of Euro-American settlement there were “still miles upon miles of almost undisturbed timber.” The only regular disturbance to these vast woodlands likely was fire, both deliberately set and naturally occurring. The variety and intensity of disturbances to woodlands increased dramatically after settlement. Northeast Iowa, which was about 60% forested in the mid-19th century, was reduced to a smattering of forest remnants as a result of logging, the clearing of trees for agriculture, the growth of towns, and the building of roads. Statewide, woodland cover 6
WOODLAND HEALTH
Woodland Structure A high diversity of native plants coupled with distinct layers of canopy, understory, shrub, and herbaceous vegetation indicate woodland health. CANOPY LAYER
taller, overarching trees
UNDERSTORY LAYER
smaller trees and woody vines
SHRUB LAYER lower-growing, multiple-stemmed, woody plants
HERBACEOUS LAYER ground layer, non-woody plants
has been reduced to about 6% of Iowa’s area compared with 20% around the time of Euro-American settlement. Not only the extent, but also the health, of our woodlands has been diminished. To a botanist or forester, a high diversity of native plants coupled with distinct layers of canopy, understory, shrub, and herbaceous vegetation indicate health. Logging and grazing have compromised both the structure (layers) and composition (species make-up) of woodlands. The canopy and understory layers often are blended, and there may be a profusion of invasive species in the shrub and herbaceous layers. Recent forest surveys point to a slow and steady comeback by Iowa’s woodlands over the last twenty years or so, suggesting that we’ve turned the corner with regard to the decline in A GLANCE AT IOWA WOODLANDS
7
woodland cover. Most of the reported expansion in Iowa’s woodland area is due in large part to the decline in the number of cattle on pasture and the resulting increase in the number of trees on land that was previously grazed. An assortment of trees in a degraded pasture doesn’t constitute a woodland, however, for it lacks both the structure and composition—and therefore the functioning—of a healthy forest community. Another significant change in our woodlands is the decrease in the number of young oaks to replace those that have been removed through harvesting, old age, or disease. Unlike shade-loving species such as maple or basswood, oak seedlings and saplings require abundant sunlight. As our woodlands become more dense with shade–tolerant trees, invasive shrubs, and exotic herbaceous plants, less and less sunlight reaches the woodland floor. With the loss of oaks—Iowa’s most prominent and important hardwood tree—from the species mix in our woodlands, the look, feel, and function of those forests change dramatically.
“It is not so much for its beauty that the forest makes a claim upon men’s hearts, as for that subtle something, that quality of the air, that emanation from the old trees, that so wonderfully changes and renews a weary spirit.” –Rober Louis Stevenson (1850-1894) Scottish writer
Value of Iowa Woodlands Historically, woodlands have provided shelter and a host of forest products such as lumber, fuel, fencing material, railroad ties, trestle timbers, and telegraph poles. Though woodlands were essential to settlement, they were at the same time viewed as an impediment by Euro-American newcomers. On encountering woodlands, their first response was to clear the trees, remove the stumps, and create cropland. Woodlands left standing often were used as grazing land for cattle and other livestock. Even now, according to the Iowa Department of Natural Resources, about 75% of Iowa woodlands are being grazed. 8
WOODLAND HEALTH
Woodlands furnish food and habitat for a variety of wildlife. Those of us who enjoy the company of wildlife, or who appreciate wildlife as a source of food or income, certainly value forest communities. The beauty of woodlands is a source of inspiration for writers and painters. Others view forests as a fount of wisdom. Still others think of woodlands as a place of renewal for care-worn souls—a sanctuary of sorts. In addition to these more obvious, enduring values of woodlands, healthy forests function as valuable biological systems. These benefits—also referred to as “environmental services”—may go unnoticed, and therefore unappreciated, but are far too critical to dismiss. Among them are the ability of woodlands to deliver these benefits: Control erosion – Woodlands intercept rainfall and slow runoff. Retain water – Runoff that has been slowed is more readily absorbed by the soil or taken up by trees and transpired into the atmosphere and is therefore less likely to transport any pollutants to water bodies. Purify water and air – Woody and herbaceous plants take up water-borne minerals and nutrients through their roots and remove pollutants from the air through their leaves. Store carbon – Woodland plants convert atmospheric carbon dioxide to biomass through photosynthesis; trees are especially important in the long-term storage of carbon as woody tissue, helping to reduce or slow the build-up of carbon dioxide— the principal greenhouse gas—in the atmosphere. Woodlands function best when all the parts—the distinct layers of the woodland, composed primarily of diverse native species— are in place. Stewardship that maintains or improves the parts of the woodland over the long run will maintain or improve the overall health of the forest. Woodland health in turn ensures the continuation of those other forest products we appreciate: namely wood, wildlife, aesthetics, and recreation. A GLANCE AT IOWA WOODLANDS
9
Getting to Know Your Woodland The first step in caring for your woodland is becoming aware of what you have. A walk through your woodland with a trusted professional, a knowledgeable amateur, or a plant identification guide is a good way to start. Take notes or photos or make drawings of what you find. The tree, shrub, and herbaceous species provide clues to the type of woodland you have. A woodland is a biological community made up of compatible woody and herbaceous plants, animals, and an array of soil life. Trees are the dominant element of a woodland community. Iowa woodlands, for the most part, can be placed in one of six communities (listed on page 9). These communities consistently occur where similar environmental conditions—such as soil, topography, climate and water—exist. Each woodland community contains species in the canopy, understory, shrub, and herbaceous layers that are particular to that community—as well as species that are widely distributed. By recognizing species and learning about the environmental conditions specific to your woods, you will be able to classify your woodland. While you’re taking stock of the type of woodland you have, you also might consider these additional questions: Are there exotic or invasive species in the woodland? What kind and to what degree? Does the woodland include four distinct woodland layers: canopy, understory, shrub, and herbaceous? Is there evidence of damage from wildlife or livestock? (A forester can help you recognize subtle, long-term changes.) Is your woodland part of a larger forested area or is it a smaller, isolated woodland? Answers to these questions offer insights to the health of your woodland. 10
WOODLAND HEALTH
IOWA WOODLAND COMMUNITIES Oak-Hickory found throughout Iowa on dry uplands or south- and west-facing slopes white oak
Maple-Oak-Basswood occurs throughout Iowa on moist, well-drained uplands or protected north- and east-facing slopes sugar maple
Bottomland Hardwoods found on floodplains and low-lying terraces in larger stream valleys black walnut
Riparian occurs as a band of vegetation along streams, lakes, mudflats, and sandbars river birch
Northern Conifer and Hardwoods rare but most likely found on steep, moist, north-facing slopes in northeast Iowa white pine
Oak-Cedar Glade occurs in extreme eastern Iowa on thin soils over limestone or other kinds of bedrock downy serviceberry
A GLANCE AT IOWA WOODLANDS
11
SOME STEWARDSHIP OPTIONS
The goal of woodland stewardship is to maintain or improve woodland health. As you become better acquainted with your woodland, you might detect signs of past disturbance. Invasive plants, gaps in woodland composition and structure, deer and livestock damage, and habitat fragmentation signal disturbance and all can threaten woodland health. Below are several stewardship options you might want to consider to counter these threats. These stewardship tools also can have the effect of protecting the associated values of woodland aesthetics, biological diversity, and wildlife habitat. For additional management suggestions, contact your district forester or other natural resource professional.
“The Lord giveth and the Lord taketh away, but he is no longer the only one to do so. When some remote ancestor of ours invented the shovel, he became a giver: he could plant a tree. And when the axe was invented, he became a taker: he could chop it down. Whoever owns land has thus assumed, whether he knows it or not, the divine functions of creating and destroying plants.”
–Aldo Leopold
Sand County Almanac
Recognizing and Controlling Invasive Plants Plants found where they do not naturally occur are considered alien, exotic, or non-native. If they also grow and spread rapidly, allowing them to establish over large areas and displace native vegetation, they are termed invasive. Ironically, many invasive plants found their way to Iowa woodlands after being introduced as species that were thought to be desirable because of their ornamental or conservation and wildlife values. Invasive species thrive in part because of the absence of natural controls, such as insect pests or disease, in their new habitats. 12
WOODLAND HEALTH
Conservation biologists consider invasion by exotic species, along with habitat destruction, to be the two great destroyers of biodiversity worldwide. Some of the known effects of invasives are: Increased pressure on threatened and endangered species and their habitats; Loss of native sources of food and shelter important to local insects, birds, and other wildlife; and Alteration of ecological processes, such as the suppression of tree seedlings needed to regenerate a woodland. The invasive plant species that most threaten the health of Iowa woodlands are garlic mustard, common buckthorn, multiflora rose, and tartarian honeysuckle. These species can invade any woodland community. Both mechanical and chemical methods can help control these invasives. Often the best approach is to employ more than one method. The aim here is to improve the understory habitat for native tree seedlings, shrubs, and herbaceous vegetation.
garlic mustard, common buckthorn, multiflora rose, and tartarian honeysuckle are the invasives that most threaten Iowa woodlands
STEWARDSHIP OPTIONS
13
(first-year clump)
(second-year plant)
GARLIC MUSTARD (Alliaria petiolata) This herb was used in cooking by early settlers who brought it from Europe. Its leaves and stems have a distinct garlicky odor when crushed. First-year plants feature a clump or rosette of scallop-shaped leaves. Mature plants, from 12 to 48 inches, have tiny, white flowers and slender fruit capsules that produce pepper-like seeds. Growth starts early in the spring, rapidly producing a dense cover that shades out tree seedlings and early native wildflowers—like blood root, trillium, and Jacob’s ladder— especially in disturbed woodlands. The seeds are carried on the feet of humans and animals, animal fur, moving water, clothing, and equipment. 14
WOODLAND HEALTH
Garlic mustard stands are found throughout the state, but most problems occur in eastern Iowa. Key to control is getting an early start before plants become widespread. Garlic mustard forms many seeds that can remain alive in the soil for as long as five years, allowing the species to quickly dominate the woodland floor. Control methods, therefore, have to be repeated, and annual monitoring is necessary. CONTROL METHODS Pulling, cutting, and use of herbicides are options. Hand pulling is a good option when infestation is light and there also are desirable native species present. Pull when soil is moist, grasping low and firmly on the plant in order to remove entire root system. Pulled plants should be bagged and removed from the site if possible, especially if flowers— with seeds in the making—are present. Contact your district forester about disposal options. Stem cutting may be preferred for larger infestations. It can be done through much of the summer. Cut stems as close to the ground as possible. If flowers or seed pods are present, bag clipped stalks and remove from the site. With mature pods, use care to avoid scattering the seed. (Some Wisconsin natural resource professionals store pulled or clipped plants in black plastic garbage bags for 2–5 years. Heat build-up in the bags kills the seeds.) The systemic herbicide, glyphosate (e.g., Roundup) is effective for very heavy infestations where the risk to native plant species is minimal. Glyphosate is quickly inactivated by soil and has no residual effects, but it will kill any plant it contacts, so extreme care must be taken to direct the herbicide and limit drift. This herbicide can be applied any time of year on green plants as long as the temperature is above 50 degrees Fahrenheit and no rain is expected for 8 hours. Early spring or late fall applications are less likely to harm desirable native plants. STEWARDSHIP OPTIONS
15
COMMON BUCKTHORN (Rhamnus cathartica) Common buckthorn originated in Eurasia and was introduced to North America as an ornamental plant in the mid 1800s. Considered a tall shrub or small tree, it can grow 20-25 feet and up to 10 inches in diameter. Common buckthorn bears round, black berries. Its dull, green leaves have tiny teeth on the margins and twigs often end in thorns. Although exotic buckthorn is recognized as a serious invader of wooded areas, it is still legally sold as an ornamental. Buckthorn’s dense growth shades out native understory plants in Iowa’s oak-hickory and riparian woodlands, especially threatening oak regeneration and native wildflower establishment. It prefers lightly-shaded areas and competes aggressively with local plants, particularly on well-drained soils. Female buckthorn shrubs can produce abundant fruit—with many seeds—yielding numerous seedlings. Seeds can remain viable in the soil for years. CONTROL METHODS Studies have demonstrated that applying glyphosate herbicide to the cut stems of buckthorn during August and September is effective in killing invasive buckthorn patches. Follow-up treatments are necessary, however. Others have reported good results in applying triclopyr herbicide (e.g., Garlon) to cut stems both between late May and October and during the winter months. Cut stems with a hand lopper or small chain saw. Apply herbicide to the freshly-cut surface. By adding blue or red dye to the herbicide solution, you’ll be able to see which stumps you’ve treated. 16
WOODLAND HEALTH
MULTIFLORA ROSE (Rosa multiflora) This plant was brought to the United States from Japan in 1866 for use as a rootstock for ornamental roses. Later, it was promoted for use in controlling soil erosion and as a “living fence� benefiting wildlife as a shelter and food source. It occurs statewide and is classified as a noxious weed in Iowa because its rampant, tenacious growth in pastures disrupts cattle grazing. Multiflora rose, like buckthorn, can form impenetrable thickets that exclude more desirable native plant species. This rose is a dense, spreading shrub with curved thorns and wide, arching stems. Clusters of small, white flowers appear in the spring followed by small, hard, red fruits (hips). Birds eat the fruit and spread the seeds. A multiflora rose plant annually may produce 1,000,000 seeds, which can remain viable in the soil for up to 20 years. CONTROL METHODS Mechanical and chemical methods are the most widely used for managing this invasive plant. Frequent, repeated cutting or mowing (3-6 times during the growing season for 2 to 4 years) is one option. To minimize disturbance in high-quality natural areas, cutting of individual plants is preferable to mowing. Application of glyphosate herbicide to freshly-cut stems may be the most effective method of control, especially if the chemical is used late in the growing season. STEWARDSHIP OPTIONS
17
TARTARIAN HONEYSUCKLE (Lonicera tatarica) This Eurasian shrub was introduced to North America as an ornamental in 1752. Relatively shade-tolerant, it occurs in forest edges and in woodlands that have been grazed or otherwise disturbed, especially in the eastern two-thirds of Iowa. Exotic honeysuckles are stout, erect shrubs growing 3 to 10 feet tall. They have smooth, bluish-green leaves, pairs of fragrant, pink to red, tubular flowers, and yellow, orange, or red berries. Honeysuckle grows in dense thickets, shading out more desirable native, understory plants, such as woodland wildflowers and young trees. CONTROL METHODS Hand pull seedlings and small plants in lightly-infested areas, taking care to limit disturbance to soil. In shaded woodland habitat, where exotic honeysuckle tends to be less resilient, repeated clipping of the stems to ground level during the growing season may be effective. However, if cut only once and left to grow, exotic honeysuckles often will form stands that are more vigorous than they were prior to cutting. Herbicide application may provide more effective control. Treat seedlings with a systemic herbicide like glyphosate applied to the foliage. In established stands, cut stems to the ground and apply glyphosate to the cut surface. Regardless of the method, controls should be applied prior to seed dispersal (late summer or fall) to minimize reseeding of the treated area. 18
WOODLAND HEALTH
Controlling invasives in your woodland requires a long-term commitment, including annual monitoring and repeating treatments as needed. Invasives can overwhelm and displace existing vegetation with stunning speed and tenacity. Many Iowa woodlands still are recovering from earlier disturbances, and will continue to undergo plant succession. Controlling invasive plants will improve the understory habitat for native seedlings, shrubs, and herbaceous vegetation, which will help ensure that your woodlands will develop the structure and composition of a healthy community. NOTICE: Mention of pesticide products in this booklet does not constitute endorsement of any material. USE PESTICIDES WISELY: Always read the entire pesticide label carefully, follow all mixing and application instructions, and wear all recommended personal protective gear and clothing. Contact your county office of Iowa State University Extension for any additional pesticide use requirements, restrictions, or recommendations.
native Iowa wildflowers - Jacob’s ladder, trillium, and bloodroot STEWARDSHIP OPTIONS
19
“He that plants trees loves others beside himself.” –English proverb
Filling in the Gaps As you become more familiar with your woodland you may sense that something is missing. There may be gaps in the structure of the woodland—the canopy, understory, shrub, and herbaceous layers may not all be present. Or desirable native species may be lacking from the community. One way to fill in the gaps is to control invasive plant species so they don’t take over native plant communities. Removing invasives can clear the way for the emergence of more desirable species. If desirable native species are lacking, you can help speed recovery by planting native trees, shrubs, vines, and herbaceous plants. The type of community your woodland represents will guide your decisions on what species are appropriate to plant. A look at a similar, neighboring woodland can provide ideas on species to include, as well. Consult a forester to be sure. Bare-root trees are the most economical to plant and the most likely to survive and thrive. Shrubs, vines, and herbaceous plants may be added as bare-root seedlings, potted plants, or seeds. Because you are planting in an existing woodland, you likely will be limited to using a hand-held auger or a shovel. Most plantings to fill in the gaps probably will be done on a small scale or in phases. 20
WOODLAND HEALTH
The Special Case of Oaks One increasing gap in woodlands across the state is the decline in the natural regeneration of oaks. Oaks regenerate from stump sprouts and from acorns, but neither avenue consistently provides numerous, viable sprouts or seedlings. In addition, most woodlands provide too much shade for sprouts or seedlings to thrive. Some of the stewardship options to counter this regeneration problem, in addition to planting oak seedlings in open areas, include: Controlling less desirable trees and shrubs that provide too much shade; Selectively harvesting groups of trees or heavily thinning to provide more sunlight to seedlings; and Harvesting trees after a very good acorn crop. (This method can create significant disturbance, though it can effectively promote oak regeneration if done properly.) The decline in oak regeneration was brought on in part by the suppression of fire during European settlement. Prior to settlement, North American Indians used fire for a variety of reasons—to promote fruit and berry production, to ready sites for crop planting, to enhance hunting success by concentrating game, and more. These generally were periodic, low-intensity surface fires ignited in the spring or fall. The thick bark of mature oaks and the stump-sprouting ability of oak seedlings and saplings enabled them to withstand these fires. Less fire resistant species did not survive, allowing oaks to become dominant. The continued suppression of fire has lead to dense stands of fire-sensitive, shade-tolerant trees at the expense of oak regeneration. Some natural resource professionals and woodland landowners are beginning to reintroduce fire to encourage oak regeneration, to control invasive plants, and to enhance the growth of desirable grasses and herbaceous plants. In some instances, you may want to consider prescribed burns as a stewardship option. Check with your district forester for information and assistance. STEWARDSHIP OPTIONS
21
Whether you encourage oak regeneration by controlling individual trees or shrubs, by harvesting groups or a large area of trees, or by burning—or if you simply choose to do nothing —your woodland will continue to change. These changes—whether natural or induced by humans—will affect woodland aesthetics as well as function. Therefore, it’s best to discuss these options and their possible ramifications with a forester or other natural resource professional before you decide on any action. While we’re speaking of gaps—one last suggestion—don’t make unnecessary gaps in the canopy by removing dead trees. If left standing, they provide food and shelter for many birds, insects, and mammals.
Limiting Damage from Livestock and Deer In a state where most of the land is tillable, many Iowans regard woodlands as a kind of wasteland. In order to put this “wasted” space to use, landowners often have used it as grazing land. Unfortunately, livestock nearly always harm woodland health by: Damaging flowering plants of the woodland floor; Opening the woodland floor to invasives; Decreasing tree and shrub reproduction (cattle are especially fond of oak seedlings and saplings); and Increasing the effects of stress and disease on trees. Grazing further degrades woodland health by reducing the amount of soil organic matter, compacting the soil, increasing erosion, and reducing soil fertility.
22
WOODLAND HEALTH
Moreover, livestock gain less weight when grazing in woodlands than they gain on improved pasture. They also may consume toxic forest plants. Often, a landowner’s most important stewardship tool is to fence livestock out of his or her woodland. Deer, especially in the numbers present across the state today, have a similar impact on woodland health. Deer browse woody plants and also consume herbaceous plants, fruits, and berries. Antler rubbing by bucks in the fall can damage or even kill individual trees. If deer damage is a concern, do not invite deer to your woodland by putting out salt or by planting special crop mixes intended to entice deer. Other more complicated and expensive control methods are excluding deer with high or electrified fence, frightening them away with exploders, or repelling them with commercial products. The most practical way to control deer damage in many cases is to allow some deer hunting in your woodland. Aside from coyotes, which will prey on fawns, deer have few natural predators. If not kept in check by hunting, Iowa’s deer herd could increase at an annual rate of 20 to 40%, doubling the population every three years.
Avoiding Further Fragmentation of Woodlands The “miles upon miles of almost undisturbed timber” present at the time of Euro-American settlement are long gone from Iowa’s landscape. Ten- to forty-acre woodlands now are the rule and tracts of several hundred acres are the exception. The cutting up, or fragmentation, of Iowa’s woodlands began with the conversion of timbered tracts to farms, towns, railroads, and roads and continues today as new housing developments, utilities, and more roads spring up in what remains of our forests. As woodlands are carved up into smaller and smaller pieces, the amount of habitat obviously decreases. In addition, more of what previously had been the interior of the woodland is STEWARDSHIP OPTIONS
23
exposed as an “edge.” Conditions along this new edge are more extreme—sunnier, hotter, drier, colder, and windier. These changed conditions can be detrimental to existing plant, animal, insect, and soil life, altering both the physical character of the woodland and its functions as a community. In Iowa and much of the Midwest, one of the effects of fragmentation has been a serious decline in the population of Neotropical migrant bird species. These birds—some familiar like the Baltimore Oriole and Barn Swallow, others perhaps less so like the Loggerhead Shrike and Kentucky Warbler—winter south of the U.S.-Mexican border and migrate north to nest. A decline in both the quantity and quality of habitat—in this case the fragmentation of woodlands in Iowa and the northeastern U.S.—is partly responsible for the threat to Neotropical migrants’ populations. Fragmentation can have similar effects on other wildlife.
You can help curtail fragmentation by Preserving unbroken, interior woodlands and limiting disturbances, such as house and road building, to already disturbed or fragmented areas; Minimizing edge by keeping your buildings clustered and near the road, rather than spread out across a larger area; Maintaining the maximum amount of habitat with the least amount of edge by encouraging circular- or square-shaped tracts rather than linear ones; and Filling in the larger gaps in your woodland by planting appropriate native trees and shrubs. To go one step further, you could work with neighbors to link your woodlands by planting native trees and shrubs appropriate to your woodland community. 24
WOODLAND HEALTH
Permanently Protecting Your Woodland Finally, you might consider protecting your woodland beyond your lifetime. Landowners who want to permanently protect natural areas—whether it’s a woodland, wetland, prairie, or other wild place—have a variety of options from which to choose. Options for protection range from conservation easements to outright sale of land to a conservation organization. You can choose to retain ownership of your woodland, pass it on to others, or create a public area. Many protection options provide landowners with compensation and/or tax benefits. Like other kinds of management choices, these options can be used alone or in combination to satisfy your wishes for the land as well as your personal financial needs. Your advisors and the Iowa Natural Heritage Foundation can help you develop a personalized plan that best suits your land and meets your needs. For more information on protection options, visit the INHF website at www.inhf.org/forlandowners.htm to view the on-line version of “The Landowner’s Options,” or call 1-800-475-1846 to request a copy. STEWARDSHIP OPTIONS
25
IF YOU WANT TO KNOW OR DO MORE
Woodlands are biological communities made up of compatible woody and herbaceous plants, animals, and an array of soil life. Naturally, you as a woodland owner are a member of this community, as well. The stewardship options we’ve suggested here are ways for you to become an even more active participant. The relationships over time among plants, animals, soils, climate, and topography—combined with the actions of previous woodland users or owners—have made your woodland what it is today. The stewardship choices you now make can maintain or improve the health of your woodland “for those who follow.” Most woodland owners can undertake a number of stewardship activities themselves. In some instances, you may want to rely on your district forester or other natural resource professionals to help you understand the management needs of your woodland; this service is often free. Too, you may enjoy learning with and from others who share your interests and concerns. Iowa State University Extension Forestry offers a variety of educational opportunities for woodland owners. Because we did not intend for this booklet to be a comprehensive management guide or manual on woodland restoration, there are a number of stewardship options that aren’t discussed. There also are many additional forestry references in addition to the partial list provided on the following pages.
26
WOODLAND HEALTH
“Few are altogether deaf to the preaching of trees, their sermons on the mountains go to our hearts; and if people in general could be got into the woods, even for once, to hear the trees speak for themselves, all difficulties in the way of forest preservation would vanish.” – John Muir, Conservationist 1838-1914
IF YOU WANT TO KNOW OR DO MORE
27
RESOURCES: Getting to Know Your Woodland Good references to consider as you get to know your woodland include the following booklets, available from Iowa State University Extension; visit the website at www.extension.iastate.edu/pubs/wi.htm (accessed April 29, 2004) or call 515-294-5247 for information. • “Iowa’s Biological Communities” (IAN 201). • “Iowa Woodlands” (IAN 202). • “Iowa’s Spring Wildflowers” (IAN 301). • “Iowa’s Summer and Fall Wildflowers” (IAN 302). • “Iowa’s Trees” (IAN 304). • “Iowa’s Shrubs and Vines” (IAN 307). • “Iowa Habitat Loss and Disappearing Wildlife ” (IAN 101). • ...and many more in the IAN series. • “Managing Iowa Habitats: Restoring Iowa Woodlands” (PM 1351i Sept. 1999). Also: • Wildflowers of Iowa Woodlands, by Sylvan T. Runkel and Alvin F. Bull (out of print, available at local libraries or through interlibrary loan and at conservation offices). • Prairie, Forests, and Wetlands: The Restoration of Natural Landscape Communities in Iowa, by Janette R. Thompson. • Nature’s Heartland, by Bill Boon and Harlan Groe (out of print, available at local libraries or through interlibrary loan and perhaps local garden club members).
Recognizing and Controlling Invasive Plants Most of the information presented in this booklet on invasive plant species and their control comes from public information sources, including the website of the Plant Conservation Alliance’s Plant Working Group; the website, www.invasive.org; as well as “Plants and Animals Threatening Our Natural Resources,” a poster distributed by the Iowa Department of Natural Resources. 28
WOODLAND HEALTH
Websites: • Plant Conservation Alliance, Weeds Gone Wild, www.nps.gov/plants/alien (accessed April 29, 2004) • A Joint Project of The Bugwood Network, USDA Forest Service, USDA APHIS PPQ and the University of Georgia, www.invasive.org (accessed April 29, 2004) • Wildland Invasive Species Team (The Nature Conservancy) http://tncweeds.ucdavis.edu/ (accessed April 29, 2004) • Wisconsin DNR, Bureau of Endangered Resources, www.dnr.state.wi.us/org/land/er/invasive/index.htm (accessed April 29, 2004) • Invasive Plants Association of Wisconsin, www.ipaw.org (accessed April 29, 2004) For additional pesticide use requirements, restrictions, or recommendations contact: Iowa State University Extension -- County offices listed under the “Government-County” section of your local phone book.
Filling in the Gaps Information on native species to plant and planting methods can be found in many of the sources identified above in “Getting to Know Your Woodlands.” Prairies, Forests, and Wetlands provides an extensive list of sources of seeds, plants, and trees. Of special note is Cascade Forestry Service, which offers a number of native, bare root tree and shrub seedlings, as does the IDNR State Forest Nursery. Missing from the source list is Ion Exchange in Harpers Ferry and Willowglen Nursery in Decorah, both of which offer native woodland wildflower and grass seeds and plants. IF YOU WANT TO KNOW OR DO MORE
29
Limiting Damage from Livestock and Deer • “Grazing Iowa’s Woodlands,” F-350 available from Iowa State University Extension. • “Managing Iowa Wildlife: White-tailed Deer,” PM1302G available from Iowa State University Extension or go to www.extension.iastate.edu/pubs/wi.htm and click on PM1302g (accessed April 29, 2004). Websites: • www.iowadnr.com/wildlife/index.html and click on wildlife damage management (accessed April 29, 2004). • http://wildlifedamage.unl.edu go to the menu and click on A Key to Your Wildlife Damage, scroll down to and click on other mammals and go to D-25, Deer; go back to menu and click on Wildlife Publications from Your University and scroll down to Iowa State University, Kansas State University, and Missouri, University of and others for more information on deer control (accessed April 29, 2004). • Iowa Department of Natural Resources Wildlife Damage Management Biologists can provide assistance: In western Iowa, call 641-774-8563 (Chariton office) and in eastern Iowa, call 563-886-3767 (Tipton office).
Avoiding Further Fragmentation of Woodlands • “A Bird’s Eye View: A Guide to Managing and Protecting Your Land for Neoptropical Migratory Birds in the Upper Mississippi River Blufflands,” by Marlene Ehresman, Iowa Natural Heritage Foundation. Call 1-800-475-1846 or e-mail info@inhf.org to request a copy.
Permanently Protecting Your Woodland • “The Landowner’s Options: A Guide to the Voluntary Protection of Land in Iowa,” Iowa Natural Heritage Foundation. Call 1-800-475-1846 to request a copy or see it online at www.inhf.org/forlandowners.htm
30
WOODLAND HEALTH
If you would like more information about voluntary land protection methods, contact the Iowa Natural Heritage Foundation staff for a free, confidential consultation. INHF has helped hundreds of landowners achieve their conservation goals. We welcome the opportunity to personally visit with those interested in permanently protecting the land they own. Call 1-800-475-1846 or e-mail info@inhf.org
For Additional Information and Technical Support • Iowa Department of Natural Resources, Bureau of Forestry. Wallace State Office Building, Des Moines, Iowa, 50319. District Foresters and other staff. Call 1-515-242-5966 or visit the website at www.iowadnr.com/forestry/ (accessed April 29, 2004). • Iowa State University, Forestry Extension 253 Bessy Hall, Ames, Iowa, 50011 or call 515-294-1458 or visit the website at www.forestry.iastate.edu/ext/ext.html (accessed April 29, 2004). • County Conservation Boards – Listed under the “Government-County” section of your local phone book. • Iowa Native Plant Society www.iastate.edu/~herbarium/inps/inpshome.htm (accessed April 29, 2004). • For information on timber production go to www.extension.iastate.edu/pubs/fo2.htm (accessed April 29, 2004) or call ISU Extension Distribution Center at 515-294-5247. Also: • A Country So Full of Game: The Story of Wildlife in Iowa, by James J. Dinsmore. • Landforms of Iowa, by Jean C. Prior.
IF YOU WANT TO KNOW OR DO MORE
31
Brought to you by the Iowa Natural Heritage Foundation with additional funding from the Roy J. Carver Charitable Trust of Muscatine, Iowa.
For more detailed information or for a free, confidential consultation on how you can protect the land you own, contact
505 Fifth Avenue, Suite 444 Des Moines, IA 50309-2321
1-800-475-1846 www.inhf.org info@inhf.org