| Governor Deval L. Patrick |
Lt.
Governor Timothy P. Murray |
EOEA Secretary Ian A. Bowles |
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Citizen Forester Electronic Newsletter Archive Previous Citizen Forester Articles
I came upon this article while researching information on the role of wildfires in the urban interface. Though it dates back to 1999 and some of the data are dated I felt that it presents a relevant perspective on the challenges we face in promoting increased canopy cover— and the associated ecosystem services—in communities. Paradoxically, although there is growing public awareness of issues like climate change, safe drinking water, organic foods and protecting open space, the single largest land change taking place in the US as land is developed from rural to suburban is the expansion of turf. As suburbs replace natural landscapes, turf replaces trees and meadows. This effects a change from low to high maintenance of the landscape, including greater reliance on petrochemicals like pesticides and fertilizers, irrigation, and fuel consumption from mowing. The typical 21”gas lawn mower running one hour produces the same amount of pollution as 11 cars driving one hour. What if a paradigm shift in land ethic was created in our urban communities empowering landowners to manage their own yards in the same ecologically sustainable ways required of our public lands? Decrying the vast expanses of lawn literally…NIMBY - Alan Snow Aldo Leopold’s Land Ethic: Is it Only Half a Loaf Unless a Consumption Ethic Accompanies It? Or Is the Shift to “Ecological Sustainability” on U.S. Public Lands Merely a Sophisticated “NIMBYism” Masquerading as a “Paradigm Shift”? By Doug MacCleery, USDA Forest Service, Washington, DC Over the last two decades there has been a substantial shift in the management emphasis of public lands, particularly federal lands, in the United States. That shift has been to a substantially increased emphasis on managing these lands for biodiversity protection and amenity values, with a corresponding reduction in commodity outputs. Over the last decade, timber harvest on National Forest lands has dropped by 70 percent, oil and gas leasing by about 40 percent, and livestock grazing by at least 10 percent. Terms like “ecosystem management,” an “ecological approach to management,” and, more recently, “ecological sustainability” has been used to describe this change in the management emphasis of public lands. Many have referred to it as a significant “paradigm shift.” Just recently, a Committee of Scientists issued a report proposing that the National Forests be managed for “ecological sustainability,” where primary management emphasis is to be placed on “what is left” out on the land, rather than “what is removed.” Commodity outputs, if they are produced, would become a derivative or consequence of managing National forests for primarily a biodiversity protection objective. Significantly, some Committee members bottomed this recommendation in part on “ethical and moral” grounds. Many have attributed the move to ecosystem management or ecological sustainability to a belated recognition and adoption of Aldo Leopold’s “land ethic”—the idea that management of land has, or should have, an ethical content. This year, celebrations are planned commemorating the 50th anniversary of the publishing of Leopold’s A Sand County Almanac, in which he spoke eloquently about the need for an ethical obligation toward land use and management. One sign that Leopold’s ideas have finally struck a chord with the larger society is that conservation issues are increasingly being taken up as causes of American churches. While a mission shift on U.S. public lands is occurring in response to changing public preferences, that same public is making no corresponding shift in its commodity consumption habits. The “dirty little secret” about the shift to ecological sustainability on U.S. public lands is that, in the face of stable or increasing per capita consumption in the U.S., the effect has been to shift the burden and impacts of that consumption to ecosystems somewhere else. For example, to private lands in the U.S. or to lands of other countries. Between 1987 and 1997, federal timber harvest dropped 70 percent, from about 13 to 4 billion board feet annually. (Note: This 9 billion board foot reduction is “log scale,” which translates into about a 15 billion board foot reduction in lumber that could have been processed from it – or about one-third of U.S. annual softwood lumber production.) A significant effect of this reduction, in the face of continuing high levels of per capita wood consumption, has been to transfer harvest to private forest ecosystems in the U.S. and to forest ecosystems in Canada. For example:
Today the U.S. public consumes more resources than at any time in its history, and it also consumes more per capita than almost any other nation. Since the first Earth Day in 1970, the average family size in the United States has dropped by 16 percent, while the size of the average single family house being built has increased by 48 percent. The U.S. conservation community and the media have given scant attention to the “ecological transfer effects” of the mission shift on U.S. public lands. Any ethical or moral foundation for ecological sustainability is weak indeed unless there is a corresponding focus on the consumption side of the natural resource equation. Without such a connection, ecological sustainability on public lands is subject to challenge as just a sophisticated form of NIMBYism (“not in my back yard”), rather than a true paradigm shift. A cynic might assert that one of the reasons for the belated adoption of Aldo Leopold’s land ethic is that it has become relatively easy and painless for most of us to do so. When Leopold was a young man forming his ideas, more than 40 percent of the U.S. population lived on farms. An additional 20 percent lived in rural areas and were closely associated with the management of land. Today less than two percent of us are farmers and most of us, even those living in rural areas, are disconnected from any direct role in the management of land. Adopting a land ethic is easy for most of us today, because it imposes the primary burden “to act” on someone else. While few of us are resource producers any more, we all remain resource consumers. This is one area we all can act upon that could have a positive effect on resource use, demand and management. Yet few of us connect our resource consumption to what must be done to the land to make it possible. At the same time many of us espouse the land ethic, our operating motto in the marketplace seems to be “shop ‘till you drop” or “whoever dies with the most toys wins.” The disjuncture between people as consumers and the land is reflected in rising discord and alienation between producers and consumers. Loggers, ranchers, fishermen, miners, and other resource producers have all at times felt themselves subject to scorn and ridicule by the very society that benefits from the products they produce. What is absent from much environmental discourse in the U.S. today is a recognition that urbanized society is no less dependent upon the products of forest and field than were the subsistence farmers of America’s past. This is clearly reflected in the language used in such discourse. Rural communities traditionally engaged in producing timber and other natural resources for urban consumers are commonly referred to as natural resource “dependent” communities. Seldom are the truly resource dependent communities like Boulder, Denver, Detroit, or Boston ever referred to as such. One of the relatively little known aspects of Aldo Leopold’s career is the years he spent at the Forest Service’s Forest Products Lab at Madison, Wisconsin. While there, he spoke of the need for responsible consumption. In 1928 Leopold wrote: The American public for many years has been abusing the wasteful lumberman. A public which lives in wooden houses should be careful about throwing stones at lumbermen, even wasteful ones, until it has learned how its own arbitrary demands as to kinds and qualities of lumber, help cause the waste which it decries…. The long and the short of the matter is that forest conservation depends in part on intelligent consumption, as well as intelligent production of lumber. If management of land has an ethical content, why does not consumption have a corresponding one, as well? Is there a need for a “personal consumption ethic” to go along with Leopold’s land ethic? In his wonderful land ethic chapter in A Sand County Almanac, Leopold wrote that evidence that no land ethic existed at the time was that a “farmer who clears his woods off a 75 percent slope, turns his cows into the clearing, and dumps its rainfall, rocks, and soil into the community creek, is still (if otherwise decent) a respected member of society.” To take off on that theme and make it more contemporary, the evidence that no personal consumption ethic exists today is that a “suburban dweller with a small family who lives in a 4000 square-foot home, owns three or four cars, commutes to work alone in a gas guzzling sport utility vehicle (even though public transportation is available), and otherwise leads a highly resource consumptive lifestyle is still (if otherwise decent) a respected member of society. Indeed, her/his social status in the community may even be enhanced by virtue of that consumption.” Ecosystem management or ecological sustainability on public lands will have weak or non-existent ethical credentials and certainly will never be a truly holistic approach to resource management until the consumption side of the equation becomes an integral part of the solution, rather than an afterthought, as it is today. Belated adoption of Leopold’s land ethic was relatively easy. The true test as to whether a paradigm shift has really occurred in the U.S. will be whether society begins to see personal consumption choices as having an ethical and environmental content as well – and then acts upon them as such. Douglas W. MacCleery is Senior Policy Analyst in the Forest Management, National Forest System for the U.S. Forest Service in Washington, D.C. To view the original article with images go to the Forest History website at: www.foresthistory.org/Publications/FHT/FHTSpring2000/leopold.pdf
This month’s lead article (written by Anne Senning) tells the story of one communities approach to reverse canopy cover loss through the establishment of a Municipal Tree July 2007 No. 116 Nursery. Once a common feature in many municipalities Citizen Tree groups are once again looking at municipal tree nurseries as a cost effective ways to improve their community tree canopy. Successful projects depend on clearly stating and defining the expectations and responsibilities of all parties involved, keeping it at a scale that is sustainable and utilizing modern nursery technology and practices to grow healthy nursery stock that will survive transplanting. The article appeared in the June/ July 2007 issue of Lexington’s Colonial Times Magazine. For more information about Lexington’s Colonial Times Magazine email them at colonialtimes@rcn.com or to read the original article with photos of planting day go to: www.mass.gov/dcr/stewardship/forestry/urban/citForester.htm and click on “Under the Canopy: Nurturing Lexington’s Tree Stock”
Nurturing Lexington’s Tree Stock When Paul Mazerall became Tree Warden in 1957, he created a tree nursery. For twenty years, close to when he retired in 1989, he ran this tree nursery on the front lawn of the DPW. It provided thousands of public shade trees that replaced the American Elm, which was declining and needed to be removed from Lexington’s streets. Paul Mazerall was also a founding member of the Selectman appointed Tree Committee and served for over two years. The new Lexington Tree Nursery has been under consideration for over a year and a half. It began with discussions in the Tree Committee, over increasing concerns with the fact that each year the number of Town trees that are removed exceeds the number of Town trees that are planted. This represents a continuing trend an overall loss of tree canopy. There is no budget to replace these lost trees. With Town finances in their current state there needed to be a creative approach to reforesting our Town. Beginning in spring of 2006, members of the Committee, at the initiation of Jim Wood began working with David Pinsonneault, Superintendent of Public Grounds and Tree Warden of Lexington, approached the Conservation Commission. Through a series of meetings and site visits, the current location off Maureen Road was approved. This is now a Conservation Commission Project carried out by the Tree Committee in cooperation with the Department of Public Works and the Friends. Dave Pinsonneault is very excited about the project. “The goal of the tree nursery is to grow the newly planted trees so they can be planted to parks and street areas throughout the town. A project of this magnitude would not be possible without dedicated volunteers.” Dave is passionate about preserving the trees in Lexington, but he is also cautious about spending. “Developing trees in the tree nursery will help to save the town money and the trees will help to beautify the town. Trees are a valuable resource.” Joyce Miller, Chairperson, Conservation Commission is an avid supporter. “The Conservation Commission is very pleased to be working with the Tree Committee on such a worthy project. For some time now we have been concerned about the replacement of town trees that have been removed, so when the Tree Committee approached us with their idea of using conservation land for trees we were very enthusiastic,” she said. “The Town used to have a tree nursery on the lawn in front of the DPW building, but we think the proposed location is a much better site. And of course we hope that they are successful.” Jim Wood Lexington Tree Committee, Project Director, stated, “The idea for a Lexington Town Tree Nursery came from Tree Committee discussions to determine the best way to reverse the removal of 70 more public trees than are planted each year, in a way that was cost effective.” He continues, “The concept of a Town Tree Nursery was developed into a reality by a team consisting of the Conservation Commission, Department of Public Works, Tree Committee, Friends of Trees, and citizens such as Guy Doran—who donated the materials and his labor assisting in the irrigation system installation.” “Our process began in 2006 with presentations to the Conservation Commission for permission to use a piece of conversation land and successfully culminated in the planting of 124 trees on April 28, 2007. We are planning on a four-year transplanting cycle from the nursery to Lexington Public Grounds.” The goal of the Lexington Tree Nursery is to provide quality, low cost trees for the Town of Lexington that otherwise would be cost prohibitive. This is done by purchasing one-inch caliper bare root saplings or young trees and growing them in a nursery for three to four years. This year the Town purchased elms, honey locust, crabapples, oaks, and lindens. When they are 2 to 3 inches in caliper they can be removed from the nursery and planted along Lexington streets or in public grounds. The nursery was laid out in four rows, 10 feet between each row to allow for mowing. The Town DPW dug nineteen-inch holes with an auger, 4 feet on center. The holes were lined with a 16-inch fiber Root control® bags, which were filled with a combination of the surrounding soil and compost from the Town composting facility. The bags were ‘planted’ leaving a two-inch lip above the level of the ground to facilitate removal at harvesting season in four years. The bags help to contain root spread and prune the roots into a compact root ball. This helps to transplant the tree without shock and can be done manually, rather than having to be dug by large machines. Before the trees were placed in the bags they were dipped in a mixture of hydro-gel, a gelatinous substance that clings to the roots and helps the plant to absorb and retain moisture. This will cut down on the need for extra watering, by reducing run off and eliminating frequent watering. Watering will be done through a connection to the Town water supply, with a drip line irrigation system. Volunteers recollection of planting day; Jewel Kuljian, Friends of Trees “I particularly enjoyed seeing all twenty of the Scarlet Oaks being planted after labeling them, delivering them to their location, watching them being planted, and seeing them all standing tall.” “I am impressed with the planning, preparation, and the collaboration between David Pinsonneault, the Tree Committee, the involvement of interested high school students, and the new Friends of Tree Board for making this happen.” Barbara Kent, Longtime Lexington Resident “I just thought it was so wonderful to see three generations of Lexingtonians volunteering to work on such a worthy project. It was really hard work we were all doing, and working together. I just felt that it was great! With the Town involved… It was really special.” Nell Walker, Lexington Tree Committee “I remembered the field from the first time we looked at it over a year ago. You could tell it had been farmed. It was a tall grass meadow filled with small black walnut trees. But it was a meadow on its way to becoming a woods.” Anne Senning, Volunteer; “There was a sense of community among the volunteers in doing a job together and doing it for the town we live in. I could look down the rows and see a line of trees where five hours before I saw only a line of holes in the ground.” TREE NURSERY START-UP COSTS Tree planting bags: $ 808.40 Hydro-gel: $ 36.85 Loader with Auger Rental: $ 293.00 120 Sapling Trees: $2,625.50 Town Labor & Equipment (Water/Forestry/Park) $2,031.07 Volunteer hours (estimated 150 hours x $10/hr) $1,500.00 Total Cost to Establish Nursery: $7,294.82
The following article was produced from excerpts of the Massachusetts Wild Flower Society Policy on Climate Change which was adopted by the Board of Trustees on March 21, 2007. To learn more about the New England Wild Flower Society and to read the policy in its entirety visit their web site at www.newenglandwild.org and click on the word Conservation or call their main number 508-877-7630 or visit New England Wild Flower Society at Garden in the Woods 180 Hemenway Road, Framingham, MA 01701.
New England Wild Flower Society Policy on Climate Change Executive Summary There is an overwhelming scientific consensus that the buildup of carbon dioxide and other greenhouse gasses, caused by human activity, is changing the earth’s climate. The burning of fossil fuels is the principle cause of the buildup but other activities contribute to the accumulation. The increase in surface temperature over the 20th century for the Northern Hemisphere is likely to have been greater than for any other century in the last thousand years, and it is projected that on a global basis in the 21st century, earth will experience higher maximum temperatures, higher minimum temperatures, more intense precipitation events, increased summer drying, and increased storm events, among other changes. These changes pose a threat to all forms of life and ecosystems and pose a direct challenge to the conservation of the flora of New England. The Society will lead and join in activities that are designed to both adapt to climate change and mitigate further changes. We will collaborate with other groups in plant conservation to adapt our conservation efforts to the realities of the changes coming to the New England landscape, based on scientific principles. The Society will also work to reduce its greenhouse gas emissions. Because information on climate change is rapidly evolving, this policy will be evaluated and modified annually. A. Background: 1. Global Climate Changes Based on the science cited by the Intergovernmental Panel on Climate Change (IPCC), there is little doubt that the earth’s climate system has changed on both global and regional scales since the pre-industrial era, with some of these changes, e.g. increased concentrations of greenhouse gases and aerosols, attributable to human activities. The increase in surface temperature over the 20th century for the Northern Hemisphere is likely to have been greater than for any other century in the last thousand years, and it is projected that on a global basis in the 21st century, earth will experience higher maximum temperatures, higher minimum temperatures, more intense precipitation events, increased summer drying, and increased storm events, among other changes (IPCC, 2001. Climate Change 2001: Synthesis report, Summary for Policymakers). A 2007 report from IPCC finds additional reinforcement for these predictions, and additional evidence for the link between these changes and anthropogenic activities. (IPCC, 2007. Climate Change 2007: The Physical Science Basis, Summary for Policymakers.) 2. Regional Climate Changes In October 2006, the Northeast Climate Impacts Assessment (NECIA), a collaboration between the Union of Concerned Scientists and a team of independent experts, released a new assessment of climate change and associated impacts on key climate-sensitive sectors in the northeastern United States (Union of Concerned Scientists, 2006.). The collaboration formulated two climate change scenarios for the 21st century, one where emissions continue to grow rapidly (higher emissions scenario), and a second where emissions grow at a slower rate (lower emissions scenario). Under either scenario the Northeast of the future will be a different place (see Appendix A for diagram of climate migration scenarios):
3. Changes in Ecosystems in New England As a result of this climate shift, changes in New England vegetation patterns have been projected, most dramatically in forest types. Current ecosystem models have great difficulty in predicting these kinds of biological and ecological response, thus leading to large uncertainties in projections. Nonetheless, general predictions include (complete citations and references in Appendix A):
B. New England Wild Flower Society Policy on Climate Change Climate change has important implications for the Society. While we support broad national and global efforts to reverse the direction of global climate changes, our actions must focus on changes in natural ecosystems and plant health in New England. To date, plant conservation in New England has been accomplished by a combination of land preservation followed by habitat management as needed to preserve target elements. Because of changes in the composition of ecosystems, and the species that make up these ecosystems, plant conservation will need to adopt a different paradigm. The concept of “native to New England” (or a state within New England) will change as native plants from the south move northward into our region. Plant community concepts will likely need revision as assemblages of plants become rearranged. Amidst these changes, difficult questions include, “What is a natural community?” “How do we accommodate shifting species and processes?” and “How do we decide which plants deserve protection as rare native plants?” The Wild Flower Society and its collaborators in plant conservation must be ready to adapt their conservation efforts to the realities of the changes coming to the New England landscape. These collaborations will need to develop the best scientific rationales for conservation action. In light of the climate disruptions cited above, the Society will adopt two approaches: Adaptation and Mitigation. Adaptation, which can be autonomous or policy-driven, are adjustments in practices, processes, or structures to take account of changing climate conditions (IPCC, 2001, Working Group II: Impacts, Adaptation and Vulnerability.) Mitigation are those actions that are taken to constrain climate change directly (i.e. a reduction in greenhouse gases) (IPCC, 2001, Working Group III: Mitigation.) Accordingly, the New England Wild Flower Society will: 1. Partner with conservation groups, to develop rational conservation strategies in light of changes to the New England landscape. 2. Advocate changes in environmental laws and programs that help to mitigate and adapt to climate changes with other conservation and environmental partners.
3. Reduce our impact. As an organization we will reduce our contribution to global climate change. Although some changes are now unavoidable, as demonstrated by the differing predictions in the two emissions scenarios of the Northeast Climate Impacts Assessment (NECIA), “the extent of change and the impact of these changes on the Northeast depend to a large degree on the emissions choices we in the Northeast and the world make today. “
4. Develop Responsive Management Strategies. We will aid in helping species move northward, if necessary, while protecting those that remain.
5. Community Awareness/Participation. The Society will continue to educate and involve the citizens of New England in mitigation and adaptive strategies. Because the effects of climate change are not certain, this policy will be evaluated and modified annually.
National Research Plan for Urban Forestry: 2005-2015 by: The National Urban and Community Forestry Advisory Council Authors: James Clark, William Kruidenier, Kathleen Wolf. View the entire Report at: www.treelink.org/nucfac/National_Research_Plan_for_Urban_Forestry_2005_2015.pdf Landscapes that include trees, parks, woodlots, greenbelts, natural areas, and native forests – both naturally occurring and planted – are found in communities throughout the United States. What makes these “urban and community forests” unique from rural forests is the dominant role of human activity in their creation and management. The term “urban and community forests” is commonly used by professionals who work with trees in urban areas and refers to the trees and forests found in urbanized settings—in the center of cities and towns, in suburbs and rural communities, and at the edge of wildlands.
How large is this urban forest? The USDA Forest Service estimates that the metropolitan areas (urban counties) of America cover 24.5 percent of the land area of the lower 48 states. Nationally, urban areas have an average tree cover of about 27 percent, compared with the national average of about 33 percent for all lands. Recent surveys of experts and scientific publications point to the urgent need for more research concerning urban forests. This report is directed to the leadership of national agencies and organizations that have the capacity to fund and conduct science concerning urban forests. The purpose is to identify and clarify research priorities in an effort to integrate urban forest science activities with other science initiatives, particularly those of the USDA Forest Service.
A Vision for Urban Forest Research Trees and forests are integral to sustaining a high quality of life in our cities and towns. Research, development, and effective communication of new science-based knowledge are increasingly needed to sustain both natural and human populations within built environments. Two broad programs of research and technology transfer have been identified:
Research Planning and Strategy The National Urban and Community Forestry Advisory Council was established by the 1990 amendment to the Cooperative Forestry Assistance Act of 1978. One of the congressional mandates is to develop “…a national action plan that includes recommendations for new and expanded research efforts directed towards urban and community forestry concerns; a summary of research priorities; and an estimate of funds needed to implement such research on an annual basis for the next 10 years.” The Council’s first urban forest research plan was produced in 1991 and has effectively guided research and technology transfer activities for more than a decade. In 2002, the Council initiated a review and update of the 1991 plan. Two processes, a national survey of experts and a research summit meeting, generated an extensive list of scientific needs and priorities. Findings are summarized in A Revised National Research and Technology Transfer Agenda for Urban and Community Forestry. In 2004, the resulting agenda was integrated with the broader research agenda of the USDA Forest Service to produce this report. Six major goals will guide efforts in research, development, and technology transfer in urban and community forestry research for the next 10 years. This plan is presented as a broad framework of national goals which, when achieved, will provide state, regional, and local communities with the information needed to effectively manage optimal health and benefits of urban forests, now and into the future. Strategic Goals
Funding Recommendations Funding for urban forestry research and related technology transfer efforts has been historically low relative to the constituency served and has failed to keep pace with population trends and resulting forest issues. More than 80 percent of the U.S. population lives in urban areas, and benefits from the forest ecosystems around them. Many regions of the country continue to undergo rapid urban growth and landscape change. Additional research is greatly needed to respond to this dramatic shift in population from rural to urban areas. Most urban forestry activity is conducted on non-federal lands. Good technology transfer processes and products are essential. Effective translation of scientific findings for local decision makers and managers is needed to achieve best management practices and better science-to-action linkages. Technology transfer should be achieved using varied communication tools and collaboration with a broad array of potential users. Ongoing communication about the measurable values of urban forests is an important research and technology transfer outcome. Demonstration of the measurable impacts of ecological and social services of urban forests will help all programs—federal to local—optimize returns on their urban forest investments. Other Federal Resources and Collaborators–USDA CSREES USDA Cooperative State Research, Education, and Extension Service (CSREES) funding is largely supported by the McIntire-Stennis Cooperative Forestry Research Program. This program supports all aspects of forestry research, primarily at the university level. Only a small portion has been historically devoted to urban forestry. In FY 2001, CSREES reported spending $1.6 million for parks/urban green space (urban forestry) research. From this investment, only $257,000 was attributed to the agency appropriations. The balance resulted from fiscal resource leveraging with state, private, and other federal sources. Universities and associated institutions are the training ground for a new generation of scientists. If research capacity is to be maintained into the future, there must be adequate support for urban and community forestry research at the university level. Moreover, universities extend the range of disciplinary expertise available to the Forest Service. Funding to CSREES programs should be increased to $8 million in FY 2010 and $20 million in FY 2015. Urban forestry research is being conducted by other federal agencies and organizations, including the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE). New collaborative efforts are under way with the U.S. Centers for Disease Control (CDC) and the U.S. Department of Housing and Urban Development (HUD). Additional collaborations should be considered with public health, urban planning, housing, and commerce departments and agencies.
Non-Federal Resources and Collaborators Little is known about urban forestry funding beyond that provided by the federal government. A 1995 report showed that nongovernmental organizations—largely arboretums, associations, and institutions—were spending about $1.5 million annually on urban forestry research. No current information is available about university spending, although the nation’s forestry school leaders have repeatedly cited urban forestry as an underserved specialty in the forestry discipline. Additional funding of extramural scientists is needed. The federal government could provide the impetus to increase funding to collaborators. For instance, more cost-share grants can be provided. Universities and non-profit organizations could increase the size of their urban forestry programs to take advantage of this source of funding. The need for urban and community forestry research, development, and technology transfer parallels the need for a sustained environmental and social quality of life in cities. Support for both the public and private sectors’ support of urban forestry science has grown, but the response has not kept up with demographic and land-use trends. Strengthened and continued investment will provide a great and enduring return in knowledge, management strategies, and realization of the many benefits that urban forests provide. January 2007 Prevention of Hazardous Tree Defects, Part II – By Gary R. Johnson, Richard J. Hauer, and Jill D. Pokorny (Following is an adaptation of the second half of an article by the authors cited above. The first half of this article was presented in the November edition of the Citizen Forester and can be viewed on the DCR web site at http://www.mass.gov/dcr/stewardship/forestry/urban/citForester.htm IntroductionIn part one of this article, the authors presented long term methods for reducing the occurrence of tree hazards. By taking steps to design a species-diverse, uneven – aged forest, match tree species to site conditions, and purchase high quality nursery stock, the authors contend that community foresters can reduce the incidence of tree hazards and the costs associated with mitigation of those hazards. In this second half of the article, the authors review proper tree planting and pruning guidelines and protection of trees from construction damage as further steps to reduce the formation of tree hazards. By observing proper planting technique, maintaining tree structure with appropriate pruning and protecting trees during construction activities, community foresters can have a positive impact throughout the life span of shade trees. Proper Tree Planting TechniquesTrees can be purchased as bare root, containerized, or balled and burlapped specimens. Basic planting methods are the same for all specimen types, but handling and special considerations apply, depending on the size and the type of tree. (A checklist of basic planting guidelines for all three types, and planting guidelines for special situations is provided in the article). Basic Planting Guidelines for All Tree Types: Match the tree species to site conditions. Base this on the soil type, soil pH, surface and sub-soil drainage, growing space, exposure factors (e.g. sun, wind, ice and snow, and de-icing salts), and the tree’s cold hardiness. Prepare the site by removing the sod. Loosen the soil by tilling or spading an area three to five times wider in diameter than the width of the root system, and only to the depth of the root system. Dig a hole in the center of this circle that is 1 to 2 feet larger in diameter than the root ball and deep enough so the root collar is at the soil surface when the tree is planted. The root collar is the base of the stem where the primary roots first begin to branch away from the stem. The root collar may be buried in balled and burlapped, container grown, or tree spade dug trees because of the way the trees are dug in the nursery. If you find the root collar is buried to 3 inches deep in the root ball, dig the planting hole 3 inches shallower than the depth of the root ball. Maintain undisturbed (not loosened) soil beneath the root ball to prevent the tree from settling. Carefully place the tree in the center of the hole and gently remove any excess soil to expose the root collar flare. Double-check that the root collar (base of the stem where the primary roots first begin to branch away from the stem) is at soil surface or slightly above (e.g. 1 to 2 inches). Planting trees at the proper depth, and not too deeply, is a critical step that can help to prevent the development of stem girdling roots and premature tree failure. Stem girdling roots can compress and kill trunk tissue, and cause trees to decline 10 to 20 years after planting or suddenly fail during storms by snapping off at the stem/root compression area. Backfill around the roots with the soil that was removed. Lightly pack or water the soil during this process to eliminate air pockets. Backfill the planting hole to the height of the root collar, but no higher. Mulch with 4 to 6 inches of coarse wood chips or shredded bark. Pull the mulch back away from the trunk to prevent direct contact with the root collar and trunk. Be sure to avoid creating a mulch volcano by applying the mulch too deeply and placing it right up to the stem. Water is very important to a newly planted tree. Newly transplanted trees will benefit from daily watering for the first 1 to 2 weeks, applying approximately 1 to 3 inches of water per caliper inch at each watering. Thereafter, water trees every 2 to 3 days for the next 2 to 3 months and then weekly until established. Remember, roots need oxygen, too! Adjust the watering schedule accordingly for rain or very dry conditions. Important “Don’t Forget” items and Planting Guidelines for SpecialSituationsThe planting guidelines given above are general in nature and apply in the great majority of planting situations. The complete article includes subsequent sections on specific “don’t’ forget to” procedures and issues that often arise during tree planting. Some of these items include steps for handling girdling roots and the special moisture needs of bare root stock. In addition, planting suggestions for dealing with heavy and/ or poorly drained soils, proper staking methodologies and many other topics are covered in these sections. Proper Tree Pruning TechniquesSound arboricultural practices will prevent development of many hazardous tree defects. Investing community resources in proper tree pruning techniques is one of the most effective tree risk management strategies. Early formative pruning and ongoing maintenance pruning will prevent the development or eliminate many tree defects that are leading causes of tree failure. Early and regular tree pruning will also reduce the costs of subsequent pruning, tree removal, and replanting. Industry standards for pruning trees are published by the American National Standards Institute in The American National Standard for Tree Care Operations – Trees, Shrubs and other Woody Plant Maintenance – Standard Practices: ANSI A300 – 1995 (ANSI 1995). These industry standards can help communities develop pruning specifications and safety regulations. Community tree care managers who write contracts and bidding specifications for tree maintenance work projects should be familiar with them. The complete article includes discussion sections related to the following pruning related topics:
Construction activities impact trees and can create or exacerbate hazardous situations. Protecting tree health and mitigating high-risk situations on a construction site is a matter of recognizing the potential impacts of construction activities, and identifying hazardous trees or defects that exist on the site. Avoiding or minimizing construction damage is a critical step in preventing the development of many hazardous tree defects, and eliminates the costs of treating construction damaged trees. Advanced planning and simple mitigation steps can minimize the risks associated with trees during and after construction. These include:
Each of these topics is addressed in detail in the complete article. The section dealing with street trees includes a comprehensive list of suggestions for avoiding or mitigating the construction effects that often have such serious negative impacts upon shade trees on our streets. ConclusionIn the urban and community setting, the actions of human beings may have become the primary influence on the health of the ecosystem and its many elements, including trees. While it is impossible to avoid the development of all tree hazards, it should be clear from this and the previous related article that humans can use our influence to greatly reduce the incidence of hazard tree defects. With thoughtful planning and proper species selection, consideration of site limitations, careful planting, prudent pruning and maintenance and effective protection, our urban and community forests will offer even greater benefits with much reduced costs, risks and liabilities. |