2006_Volume13_Issue2 by Public MNTCA

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By: Dave Hanson Growing up I had the privilege, yes, the privilege to witness a most unique event, a diviner. I know this term is typically linked with clerics or persons with godlike, superhuman powers. However, this man was very special to my family, yet I wouldnâ&#x20AC;&#x2122;t put him on a pedestal (God rest his Soul) nor could I see him in the company of clerics. Yet, as a diviner (maybe you are more familiar with the term dowser), I would have to say I never saw his equal. Maybe, just maybe this is true because, never since and probably never again will I witness someone who not only believed in a divining rod, but would actually put it to use for our amazement (or amusement). Ed Dienhart was this manâ&#x20AC;&#x2122;s name and he and his wife Anna were lifelong residents of Guckeen, Minnesota where I grew up. Ed and

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Quick Hits ... Hi TCAs and TRE Friends, I just wanted to send out a quick message to thank you all for helping out at TRE on Saturday, May 6th. Many hands make light work is especially true when it comes to pruning and mulching! Our little "diamond in the rough" is well on its way to recovery due to your help and hard work! >'&

And, while the volunteer day for the 13th of May was cancelled – stay tuned!

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I am currently looking at setting something up for June, right now it' s looking like the 2nd Saturday, the 10th. Our first tour (the National Urban and Community Forestry Advisory Council) is on the 13th of June, so that date would be an ideal, last-minute "spruce-up.”

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Please let me know if any of you are interested in helping out on that date. We will probably keep a similar format (i.e. 8 am to noon with an hour for continuing education and lunch). Thanks! Chad So, Keep June 10th (8 am to Noon) open if you are interested in helping… Again, contact Dave (dlhanson@umn.edu) or Chad (gibli002@umn.edu= %

By the time this newsletter arrives in your mailbox - Arbor Month (the month of May) will be winding down. We had the opportunity this year to kick off Arbor Month with the Minnesota State Fair Foundation. Twelve “Dutch elm disease” resistant elms were planted on the north end of the fair grounds. So, if you find yourself north of Lee Avenue, south of Murphy Avenue between Underwood and Cosgrove streets - this is the area at the north end of the “Sky Glider” - you can take a look at six of these elms and see how they are doing. 2

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Answers To Spring Time Questions About Trees... By: Cliff Johnson

My phone' s been ringing with spring gardening questions. Homeowners are taking their early spring walks around their yards and discovering problems and questions. The questions don' t all have easy answers. "Why are the squirrels stripping bark off tree branches? This seems like peculiar behavior." Before moving to Chaska, I watched squirrels strip bark off branches of a 20-yearold sugar maple in my Minneapolis yard. Apparently not even the experts can explain the squirrels'motivation. Best answer I' ve read is that squirrels tend to get squirrely (i.e., rambunctious) in the spring, much like some humans. The bark stripping will likely cause the affected branches to die but shouldn' t cause long-term

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damage to the tree.

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"Why are the needles on my arborvitae and yews so brown this spring?" Unlike deciduous trees that drop their leaves and go dormant during the winter, evergreen trees and shrubs (conifers) retain their leaves (needles) and, as a result, give off moisture throughout the winter. Since the ground is frozen in winter, evergreens are unable to replenish their moisture reserves from their roots. As the needles release moisture, they turn brown. Several weeks ago the yews in my yard were nearly 50% brown but they have greened up nicely since then. If you still have brown foliage in late May or early

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June, it will probably not green up and can be pruned back to green tissue.

The best time to prune most trees and shrubs is during their dormant period in the winter. Oaks must not be pruned during April, May or June because pruning during these months puts the trees at risk of oak wilt disease. Maples and birch trees should not be pruned until they are fully leafed out because pruning right now will cause them to bleed sap. Early blooming shrubs such as lilacs and forsythia can be pruned immediately after blooming. In general, hold off pruning all trees until midsummer or, better yet, next winter. "What can be done to prevent sawfly damage to spruce trees?"

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"What trees should not be pruned at this time?"

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Sawfly larvae are 1-inch green worms that show up just as Colorado blue spruce and other spruce trees send forth their tender new needle candles. I inspect my spruce every day during the spring growth flush and apply an insecticide labeled for sawfly when I first detect the presence of sawfly larvae. Sawfly larvae seem to be cyclical; infestations are worse some years than others. So, pay close attention to your spruce during May and early June. "What' s the best way and best time to fertilize trees?" The best indicator of whether fertilization is necessary is a soil test. Ideally, a soil sample should be taken before trees are planted. Additional samples can be taken & A = % B7,C7,--.

every 3 to 5 years thereafter to determine whether any nutrients are lacking. A soil test kit may be obtained from your county extension office. In the absence of a soil test, the best indicator of the need for additional fertilization of established trees is shoot growth. If new shoot growth (growth occurring in the present year) is in excess of 6 inches, then fertilization is probably unnecessary. If shoot growth is between 2 and 6 inches then fertilizer may be needed. If shoot growth is under 2 inches, fertilizer application is advised. Most trees experience a single flush of growth during spring followed by slower growth throughout the summer and fall. Because of this single flush of growth, it is desirable to have nutrients available as this growth is about to occur. The most beneficial time to apply fertilizer is from when the ground is workable in the spring until just before trees start growing in early May. On sandy soils, applications should be split, half in early spring and half in mid- to late-May. High rates of phosphorus (P) fertilizer should not be used unless a need is indicated by a soil test. If soil test indicates adequate levels of P, then it is best to use fertilizers such as 24-0-15, 30-0-10, 32-3-10, 18-5-9, 27-3-3, or 16-4-8 with a high rate of N and a low or zero rate of P. High rates of P can negatively affect the environment by causing excessive algae to grow in nearby lakes and streams which will, in time, kill fish and other aquatic life.

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Never use a fertilizer that includes any kind of herbicide around a tree. These fertil)7

izers may be beneficial to turf, but can damage trees.

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section of the University of Minnesota Extension Service website:

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An excellent tree fertilization guide is available online in the gardening

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http://www.extension.umn.edu/distribution/horticulture/DG7410.html .

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Anna were phenomenal friends and neighbors to my parents and I could tell some stories, but - I had better get this article back on track. Ed’s divining was a pretty cool trick, I cannot tell you what Ed used as his divining rod I suspect welding materials, but that detail didn’t much matter to me at the time. Yet, thinking back on the event, I suspect his divining rod was not the “real deal.” You see the “real deal” divining rod, according to some sources, would have been a branch of hazel and not just any branch, but a forked branch oriented on the shrub with the points of the branch ends pointing; one to the north and one to the south. Another detail, in the New World that branch came from “witch” hazel. From Wikipedia, An epigram by Samuel Sheppard, from Epigrams theological, philosophical, and romantick (1651) runs thus: 7

Virgula divina.

"Some Sorcerers do boast they have a Rod,

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Gather'd with Vowes and Sacrifice,

And (borne about) will strangely nod

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To hidden Treasure where it lies;

Mankind is (sure) that Rod divine, For to the Wealthiest (ever) they incline." Donald Peattie discusses the origins of the name “witch hazel” at some length in his book A Natural History of Trees of Eastern and Central North America.. But, whatever the origins behind the name he points out that witch hazel (Hamamelis virginiana) branches were the preferred tool of early American

“witches” when divining or dowsing was the task at hand.

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characteristics led early “believers” of the mystical arts to impart powers unto this

plant. For instance, witch hazel, unlike any other woody plant that I am aware of blossoms late autumn. Even in Minnesota, I have photographed the blossoms as late as mid November into early December. The small yellow blossoms have four contorted or twisted thin petals and aren’t by any means showy, but any little bit of color is a plus as we prepare for the looooong winter ahead. Uniqueness does not end with the late flowering. The fruit capsule is about ½ inch long and is elliptic or urn shaped with a 4 part calyx at the base. The capsule typically contains a pair of fruits that are said to be edible. Witch hazel’s fruit capsule is intriguing in that the seeds are forcibly ejected from the capsule. It is re&

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Witch hazel is a unique plant in many regards and its unusual “mystical”

ported that when ejection occurs there is an audible snap as the

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Do Trees Heal When Wounded? By Justin Hartzell, Guest Columnist... Many people may remember a tree that caught their eye in the past. It was often the tree that we built our tree-houses in, hid behind or simply climbed when we were kids. As weâ&#x20AC;&#x2122;ve aged, it slowly became the tree that we had to mow around, rake under or yell at as we stepped on fallen twigs or acorns. Even though we might take our special tree for granted most of the time, it holds a special place in our heart and we would miss it if it were gone. People donâ&#x20AC;&#x2122;t often think about what they are doing or realize that their habits are harmful when they mow too closely and scrape off some bark or nail a few steps to the side of it leading to the tree house. Many people think that slapping some black paint on, or using tree wrap will solve many problems and the tree will heal. They are wrong. ) "

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No Bandages? Trees do not heal like people or animals heal. They can not shed dead cells and simply replace them with new ones, they do not form seals. Trees have evolved over a period of 200-400 million years. In all that time, trees have developed a highly compartmentalized structure. When a tree is wounded, instead of healing the injured cells, they are compartmentalized or physically separated from the uninjured and living cells. This process of compartmentalization is called CODIT or Compartmentalization Of Decay In Trees. Alex Shigo is credited with developing the present day view of CODIT. Dr. Shigo was the chief scientist with the U.S. Forest Service from 19591985. After approximately 15,000 tree dissections, Dr. Shigo published findings on CODIT that are now widely accepted. Dr. Shigos findings are summarized in the following paragraphs.

Protective Walls Over time, trees have developed a system of four walls or plugs that separate the injured cells from the non-injured cells. Wall 1 (see Figure 1 on page 15) consists of the vertical vascular tissues, such as the phloem and xylem, which are normally used to carry nutrients and water up and down the tree. After a tree is wounded, for instance by a lawn mower, the phloem and xylem directly above and below the wound are plugged using several different types of gummy substances. Wall 1 is the weakest of the four walls of compartmentalization. Wall 2 (see Figure 1 on page 15) is made up of the

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Trees Shouldn’t Be Planted over Septic Systems…or Should They? By Bruce Labno, Guest Columnist... The Experts Should Know!!??? Check the homeowner guides and manuals for managing septic systems. Read the extension service bulletins. Don’t plant trees on the drainfield is what they say. The experts should know. That’s were we go to find the information we need, right? After all, the University of Minnesota Extension Service’s Septic System: Owner’s Guide says: “…Do not plant trees or other plants with deep, invasive roots within 5 feet of the soil treatment system.” The University of Wisconsin-Extension Service clearly states: “The drainfield is a delicate structure. Take care not to plant deep rooted trees near the system.” And, the Iowa Department of Natural Resource’s publication: Residential On-site Wastewater Treament: An Overview, mirrors Minnesota with the warning about deep roots and five feet from the drainfield. But, the clincher is the environmental knowledge base of the U.S. Environmental Protection Agency. Their, A Homeowner’s Guide to Septic Systems, says: “Plant only grass over and nearby your septic system. Roots from nearby trees or shrubs might clog and damage the drainfield.” These experts should know, right? Yes, the conventional wisdom suggests tree roots will migrate towards and eventually invade the drainfield pipes causing failure of the septic distribution system. Why risk having tree roots invade and disrupt or damage your septic system? The University of Minnesota Extension Service guide: “Landscaping Septic Systems” even suggests “Trees should be planted a minimum of 20 feet from the edge of the mound.” Wow. Then how far should a tree be from a drainfield? What if a home is in a dense woodlot? Does the owner have to clearcut the woods? Well, the Wisconsin Department of Commerce Manual for Private Onsite Wastewater Treatment Systems says, “…If no other site is available, trees in the distribution cell area must be removed.” Sounds pretty convincing. Research, Conventional Wisdom and Practical Thinking But on what research did these agencies base their recommendations? Quite frankly: none. A review of the professional and peer-reviewed literature on research related to trees and septic systems shows…nothing. There is virtually no research on how tree roots (and other roots) affect septic

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Trees over Septic Systems… continued system drainfields. All of the evidence is hearsay and based on “contractor” experience, so the manuals suggest tree roots could be a problem. Practitioners in the field do weigh in on the topic. Herb Reed, County Extension Director in Calvert County, Maryland, notes that his office has “experience with the problems that tree roots can cause in septic drain fields,” but further goes on to admit, “It is true that certain fibrous rooted trees and shrubs would probably not be a problem in most drain fields… Given all of the ambiguity we err on the side of caution and say: don’t plant trees and shrubs on drain fields.” …Ahhh, conventional wisdom and conventional conservatism. Closer to home, Diana Alfuth, Horticulturist with the University of Wisconsin Extension Service in Pierce County is a little more pragmatic about the topic. “What you get,” Diana says, “are separate camps. Camp One says, “Don' t plant ANY woody plants on or near the mound.” The concern is that the tree roots will grow into the perforated drainage pipes and plug them. You' ll see recommendations, including those from the U of M, saying don' t plant trees within 20 feet of a septic system. However, Camp Two will counter that 80% of a tree' s roots grow in the top 12 inches of the soil, where they can get oxygen from the soil.” Dr. Jim Calkins, Education Specialist in the University of Minnesota’s Department of Horticultural Sciences, falls into “Camp Two.” Not only does he agree with Diana’s comments, he notes “…drainfields are designed not to have water in them at all times, are at a depth that should be sufficiently below the normal root zone for most trees and are usually limited in oxygen.” Diana adds, “…a tree' s roots grow up to 3 times as far out as the drip line, so being only 20 feet from the drain field when planting probably wouldn' t be enough anyway.” But, the words of Herb Reed still cause hesitancy…tree roots do get into drainfields. Washington County Senior Environmental Specialist, Pete Ganzel, has concerns with the “tree root thing”. “I’ve been at more than 800 sites over the last 15 years where failed drainfields were being replaced,” he said. “Tree roots created a problem at only one site…and that was because of poor drainfield design and installation.” He went on stating he approves septic systems in wooded areas and near trees and the practice is not a violation of the county ordinance or state regulations. The only concern Pete has with septic system installation in wooded areas is the potential damage to trees. Pete works with the contractors and the homeowners on that issue… Pete is a forester. What about the Regulations?

Trees over Septic Systems… continued The Washington County ordinance parrots the Minnesota Rules Section 7080 which say: “A vegetative cover shall be established over the soil treatment system. The soil treatment system shall be protected until a vegetative cover is established. The vegetative cover established shall not interfere with the hydraulic performance of the system and shall provide adequate frost and erosion protection.” Nothing about trees…and surprise, surprise…there is nothing about trees in the Wisconsin or Iowa Administrative Codes either. So save the forest, sans a few trees for the drainfield, practice good tree care and good construction practices. The trees and shrubs won’t hurt a properly designed septic system. And by the way, Dr. Calkins notes, the University of Minnesota Extension Service “Landscaping Septic Systems” is being rewritten. Check These Out Understanding how your septic system works and the best practices for keeping it functional is of vital importance to the environment and the health and welfare of you and your family (and your neighbors too). Use the following valuable publications for assisting your understanding…and don’t worry about the trees they will take care of themselves… •

United States Environmental Protection Agency, 2002, Revised March 2005. A Homeowner’s Guide to Septic Systems. Office of Water, EPA-832-B-02-005.

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University of Minnesota Extension Service, 1997. Septic System Owner’s Guide. Extension Publication: PC-06583.

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University of Wisconsin-Extension, 2002. Care & Maintenance of Residential Septic Systems. Cooperative Extension Publications, Madison Wisconsin, Report No. B3583.

The following references were used in support of the “newspaper article”. References: • Iowa Administrative Code, 2005. Sections 128 and 129. • Iowa Department of Natural Resources, 2003. Residential On-site Wastewater Treatment: An Overview. • Minnesota Rules, 2005. Section 7080. • Personal Communication, March 14, 2006. Diana Alfuth, Horticulturalist, University of Wisconsin Extension Service, Pierce County Office. • Personal Communication, March 15, 2006. Pete Ganzel, Senior Environmental Specialist, Washington County, Minnesota Department of Health and Environmental Safety. • Personal Communication, March 14, 2006. Herb Reed, County Extension Director, Calvert County, Maryland. • Personal Communication, March 21, 2006. Dr. James B. Calkins, Education Specialist, Department of Horticultural Science, University of Minnesota. • United States Environmental Protection Agency, 2002, Revised March 2005. A

Trees over Septic Systems… continued • • • • •

Homeowner’s Guide to Septic Systems. Office of Water, EPA-832-B-02-005. University of Minnesota Extension Service, 1998. Landscaping Septic Systems. Extension Publication: FO-06986. University of Minnesota Extension Service, 1997. Septic System Owner’s Guide. Extension Publication: PC-06583. University of Wisconsin-Extension, 2002. Care & Maintenance of Residential Septic Systems. Cooperative Extension Publications, Madison Wisconsin, Report No. B3583. Wisconsin Administrative Code, 2005. Sections 83 and 84. Wisconsin Department of Commerce, 2001. In-Ground Soil Absorption Component Manual for Private Onsite Wastewater Treatment Systems (Version 2.0). Division of Safety and Buildings, Report No. SBD-10705-P (N.01/01).

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By Glen Hambleton - Ramsey County, TCA I live in a townhome complex, and serve on the Board of Directors with responsibility for landscaping issues. The complex is now some 40 years of age, and the original landscaping included lots of trees. Recently, a homeowner was advised by a contractor that the damage occurring to the basement wall was due to a large tree about 12 feet out from the cracked concrete basement wall. This is one of the few homes in the complex with an unfinished basement. Several other homes have trees in similar proximity to the building, but also have paneled basement walls, so if there is cracking of the concrete blocks taking place, paneling and insulation would have to be removed. If indeed, the tree were the culprit in the case of the unfinished basement, what steps would be necessary for those homes with finished basements? As a TCA, I immediately turned to several local, but nationally recognized authorities on trees in an urban environment; Dave Hanson, Gary Johnson and Patrick Weicherding. Patrick was the first to respond, stating he had dealt with this question while in Illinois, and informed me that trees damaging basement walls is a myth. He also suggested going on Google on the internet and searching for "tree roots, foundations." Dave Hanson was next to chime in, also stating that while tree roots are "opportunistic" and will go where moisture and nutrients are available, they must also have access to oxygen, and seldom go deep enough to cause damage to properly constructed building foundations or walls. Use your favorite internet search engine or Google "tree roots, foundations" to dig up all kinds of information on what is a controversial topic. One very interesting distinction quickly becomes evident: there are lots of contractors who will repair tree root damaged basement walls, and numerous educational institutions that report on research that demonstrates tree roots do not damage basement walls. 01

Welcome the TCA Class of 2006... The Minnesota Tree Care Advisor family continues to grow. As you will see in the following list, participation in the program remains strong from the Metro counties. However, Winona County’s participation in the program was strengthened this year, while the reach into Western Minnesota came to us from Renville and Douglas counties. So, without further introduction: Here is the class of 2006… Steven Lott

Dakota County

Stephanie Lake

Dakota County

Faith Appelquist

Dakota County

Lori Anderson

Renville County

Carol Krajewski

Wright County

Shirley Jonas

Dakota County

Janet Pauley

Goodhue County

Grace Anderson

Hennepin County

Dick Dostal

Washington County

Susan LaFond

Washington County

Patricia Ericson

Ramsey County

Nancy Reynolds

Winona County

Patricia Johnson

Dakota County

Bruce Kolberg

Dakota County

Lisa Lukens

Dakota County

Larry Zilliox

Douglas County Regional Extension Educator

Pat Gottschalk

Hennepin County

Michelle Nun

Anoka County

Barbara Gasterland Hennepin County Robert Kriesel

Washington County

Becca Bastyr

Hennepin County

When you have a chance please welcome these people to the TCA program. We’ve already had the chance to work with some of these Folks …. And, we’re looking forward to more!

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capsule ruptures. This is reported to be rather spectacular if autumn flowering branches with maturing fruits are brought into a nice warm house. The smallish, black, edible fruits are said to be ejected up to ten yards. A side-view of the terminal bud, really a folded leaf, brings to mind the foreleg of a deer. The buds are fairly small at ½ to ¾ inches long and the naked buds sit on a short stalk. The alternate, simple leaves are 2½ to 6 inches long by 1½ to 4 inches wide with coarsely, wavy toothed margins. The summer color is green and fall brings on a nice golden-yellow color. The leaves are two-toned with the green upper surface ) "4

and a paler, hairier underside.

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it is said, may have played a part in the name ‘witch.’ Amongst the various specula-

The leaves and fruit bear similarities to native hazels (Corylus species) and

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tive stories about the origins of the name the leaves and the fruits are described as having been a confuser (witcher) for early settlers looking for hazel nuts.

Witch hazel (Hamamelis virginiana) is the hardiest of the Hamamelis and is native to southeastern Minnesota’s moist woodlands. It can be found along stream banks and in river bottoms, but is just as likely found in upland areas. Typically, witch hazel is shrub-like in Minnesota with multiple stems and the height (typically 15 feet) seldom exceeds 25 feet anywhere in its range. Over the years, other Hamamelis species have been imported for use in landscapes. H. mollis and H. japonica are both imported species, but in Michael Dirr’s text, Manual of Woody Landscape Plants, the longest treatment is given to H. x intermedia, a late winter flowering hybrid cross of H. mollis and H.japonica. Witch hazel is intriguing for many reasons, not only for the unique, odd features of the plant, but consider the long history of humans using this plant for one reason or another. The mystical powers bestowed on this plant are a small part of

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its association with humans. While the fruit is edible and important to wildlife it appears that it was only an occasional food source to humans. However, beginning with Native Americans and continuing to this day, witch hazel has been used heavily not only as a toiletry item but for many medicinal purposes. Witch hazel ‘waters’ to ‘creams’ are marketed as astringents, after-shave lotions, anti-diarrhea medications, hemorrhoid creams, creams for varicose veins, hair products and the list continues. Many of these products are reductions from the leaf extracts of witch hazel while some are produced from twig extracts. Use your favorite internet search engine and type in the keywords “witch hazel” and the range of products and herbal medications will simply amaze. No longer is witch hazel simply a shrub that provides a dowser with the best “witching-rod”, but it is an interesting landscape plant and it is a plant that provides many intriguing products.

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In a nut shell, what I learned from this exercise about tree roots and foundations is as follows: •

Tree roots tend to be in the top 2 feet of soil, with 90% of them in the top 1 foot. Tree roots radiate out from the trunk to a distance as far as three times the height of the tree. The roots will not grow where there is no oxygen in the soil, so generally do not grow down along foundation walls, or under wide areas of pavement or other "non-breathing" surface. Tree roots do extract significant amounts of moisture from the soil.

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Foundations and concrete block basement walls do crack due to the swelling and shrinking of surrounding soils and due to the changes in soil moisture levels. Wet soils expand and dry soils shrink. Trees can contribute to soil moisture level changes when soil moisture is low. That is, the tree will continue to seek out and extract what moisture it can during periods of drought, contributing to some extent to soil shrinkage. Properly constructed foundations and walls should not be affected by the shrinkage due to the extraction of moisture by the trees.

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Planting flowers, keeping them fertilized and watered along a concrete wall will result in the "invasion" of tree roots into the area. Doing this kind of gardening will also contribute to the changes in moisture levels in the soil below the garden area. This is one form of tree roots being opportunistic. Another form is when tree roots penetrate drains. Some drains will "sweat," and the resulting moisture on the drain surface will encourage root growth. Any small break in the drain line out of which moisture emerges is also a location for encouraging root growth. To say it another way, a break in the drain "invited" in the tree roots; the tree roots did not create the break.

What is relayed here is not the whole story of the tree in question where I live, but it has been an interesting exercise in gaining insight on what is also a highly emotional topic. Here are just some to the web sites I looked at in educating myself on this topic. Hope this information is of use to more TCA' s. •

http://www2.ville.montreal.qc.ca/jardin/en/info_verte/arbre/ racines_fondation.htm

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http://www.arborday.org/trees/nineThings.cfm (Go to "Where Roots Really Grow")

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http://www.arborday.org/trees/nineThings.cfm

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http://www.planning-applications.co.uk/treeroots.htm

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http://warnell.forestry.uga.edu/service/library/index.php3? docID=22&docHistory%5B%5D=2&docHistory%5B% 5D=22&docHistory%5B%5D=152

Do Trees Heal ? … Continued from Page 6 last row of cells that are developed each year before a tree enters winter dormancy and is the second weakest wall. These cells are visibly darker than the rest of the wood and we call them growth rings. Wall 2 keeps the decay from spreading inward toward the center of the tree. These cells that make up wall 2 are continuous except where the sheets of ray cells intercept them. The sheets of ray cells make up Wall 3 (see Figure 1 on page 15). The ray cells are like the banks of a river; they dictate the flow of water, but even river banks can’t hold back a flood. Wall 3 keeps the decay from spreading horizontally too fast. The sheets of ray cells vary greatly in length, height and thickness. At the time of wounding, wall 3 is the strongest.

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Wall 4 (see Figure 1 on page 15) is developed by the forming of the first new cells after the time of wounding. The new wall is both a physical and chemical barrier. The tissue formed by this new cell wall separates the wounded tissue from the tissue that is formed as the tree continues to grow. Overall, Wall 4 is the strongest barrier of them all.

So What? The average homeowner likes a home with trees around it. A good sized tree has the ability to raise the property value of your house a considerable amount. If you continue to scrape the bark off your tree with your mower or drive a bolt through it as support for your hammock, the tree might overtime decline and decay until it dies. The trees you loved to play in and around when you were a kid could be gone long before you.

Hazard! A declining tree with decay inside can become a hazard to you and the people around you. Wood decay in the stem of your tree can have the result of a leak in your roof, not to mention a new skylight after the tree is removed. All it really takes for your tree to fall down when it is rotting away on the inside is a good strong wind from a spring thunderstorm.

Don’t Worry…Be Happy! Accidentally wounding a tree is not the end. As was said, they have evolved for millions of years and can handle some wounding. The key to the long lifespan of your tree is to keep it healthy with proper watering and avoid or eliminate wounding. Also, before you start planting trees in your yard, do some research. Some trees are able to compartmentalize better than others. A couple trees that you might want to avoid wounding are the silver maple, com-

Do Trees Heal ? mon hackberry and basswood. A few trees that compartmentalize well are sugar maple, black walnut, ironwood and bur oak. Also, some trees are more adapted to growing in certain areas. You can check out the multitude of available arboricultural or horticultural websites as well as your local DNR website and local arborist. Knowing what tree is right for you is the first step in ensuring a long and beautiful life together.

For More Informationâ&#x20AC;Ś Shigo, Alex,; Marx, H. (1977) Compartmentalization of decay in trees. U.S. Department of Agriculture. Forest Service Tree decay: an expanded concept. U.S. Department of Agriculture. Forest Service. http:// www.na.fs.fed.us/spfo/pubs/misc/treedecay/cover.htm. August 1997 Mooter, Dave,; Kuhns, M. (2002) Tree injuries: prevention and care. Utah State University. http:// extension.usu.edu/ forestry/HomeTown/Care_Injuries.htm

Harris, Richard,; et. al. (2003) Arboriculture: Integrated management of landscape trees, shrubs, and vines. 4th ed. Prentice Hall. Johnson, Gary. Professor of Urban and Community Forestry, Department of Forest Resources, University of Minnesota-Twin Cites. 2006.

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