Spring_2009 by Minnesota Shade Tree Advisory Committee

Vol. 11, No. 2

Spring No matter how long the winter, spring is sure to follow. ~Proverb

s Minnesotans, we have to keep reminding ourselves that winter will end. As natural resource professionals, we become hesitant as we schedule field activities and tree planting for early spring. We hold our collective breath as sixty-five degree days hover just above freezing at night. We learn how to balance these risks, and take solace in the fact that we are not alone. We find peace in our common bond, and in the positive energy that flows with spring.

City of Saint Paul, Department of Parks and Recreation, Mueller Natural Resources Unit ByandKarl Adam Robbins

The first day of spring is one thing, and the first spring day is another. The difference between them is sometimes as great as a month. ~Henry Van Dyke Saint Paul Parks and Recreation natural resources staff members have recently established a new, internal bond. Our Forestry section, the Environmental Services program, and the Arts and Gardens program have merged to create the Natural Resources Unit (NRU). This newly created unit will allow us to combine forces and to streamline our operations. By creating the NRU, the Department is better positioned to maximize the skills of our natural resources staff, efficiently utilize available resources (both human and non-human), effectively collaborate, and engage more with the community. City of St. Paul... continued on p. 13

The Minnesota Shade Tree Advisory Committee’s mission is to advance Minnesota’s commitment to the health, care and future of all community forests. ADVOCATE • Spring 2009

Inside This Issue 2 Together We Take MNSTAC Into The Future 3 Mystery Tree 4 A Volunteer Inventory Can Be an Option For Your Community 6 Tree Hazard And Risk 9 The Case For A Street Tree Master Plan 10 Five Steps To Keeping Trees And Woodlands: Step 3 15 Board Member Bio 16 Arbor Month

Visit MnSTAC on the Web at www.mnstac.org

Photo: Angela Koebler

COMMUNITY FOREST PROFILE

2009

Together We Take MnSTAC into the Future By Katie Himanga

I welcome the opportunity to serve as president of MnSTAC and look forward to working with you in the years ahead. Let me begin with an introduction and share what I see as the future of urban forestry in Minnesota. While I pursued a degree in forest resources from the University of Minnesota, I worked as a lab technician for Dr. David French, the forest pathologist who first diagnosed Dutch elm disease in Minnesota. Little did I know the influence this remarkable mentor would have on me and another student employee named Larry Himanga. Now a DNR forester, Larry and I share marriage, mortgage, three children and a dog. We live among trees in a house we designed and built 25 years ago. Our roots are in Minnesota. It is where we belong and like it best. I recently completed a four-year term as the mayor of the City of Lake City. When I imagine the future of urban and community forestry, this is what I see:

of caring for our treasured tree resource. Premier among them is MnSTAC.

Trees addressed in every city comprehensive plan;

To achieve this vision will not be easy. It will take patience, persistence, and a clear message presented in a professional manner. We must find our way to the table and then take our place.

Urban forests recognized and managed as a public works asset like traditional built infrastructure; Plan review comments of professional foresters as common in the agenda packets of planning commissions and city councils as the comments of professional engineers; and Trees and natural areas treated as integral to stormwater management, wellhead protection, energy conservation, and community development. Organizations flourish, whether formally organized or ad hoc groups. They educate and advocate. They bring people together to do the work

It is an exciting time to be involved in urban and community forestry. A national dialog on sustainability and climate change is underway. There is renewed focus on the natural resources and natural systems that are integral to our health and quality of life. The opportunity is here. Please join me in leading MnSTAC into the future. Katie Himanga is the President of MnSTAC. She can be reached at 651-380-9680 or khimanga@ embarqmail.com

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Mystery Tree...

Is this tree a member of the pine family that loses its needles in the fall? Or could it be a dead spruce? Alive or dead, this tree is native to Minnesota and is found throughout the state. It is concentrated in the northern section and in stands with other Pinaceae (Pine family) relatives.

Since this tree does not do well in the shade, it would be appropriate for sunny locations. It grows best in moist, well-drained, acidic soils, which consequently, eliminates most urban yards! Cones found on this tree, approximately ½ inch long, put it into the Pinaceae family. Many of the needles are borne in clusters or tufts of 15-35 needles along the branch from spur shoots.

Photo: Rebecca Koetter

Is this tree a spruce since it has no needles and looks totally dead this winter? Hint – Look along the branches for spurs.

Answer on page 14 ADVOCATE • Spring 2009

DISPEL-A-MYTH

A Volunteer Inventory Can be an Option for Your Community By Gail Nozal and Stephen Nicholson

Many of us look out our kitchen window every morning and admire the beauty of the trees in our landscape. There are even a few of us that look out that same kitchen window and wonder how many trees are in the yard, neighborhood, city, county or even our state. While it may be easy to figure out how many grow in your yard, it requires a bit more effort and planning to count or inventory trees in your neighborhood or community. As a city forester or natural resource professional, you may have thought about conducting a tree or natural resource inventory in your community. An inventory is an essential planning tool for your community that lets you know what you have and functions as a baseline for such things as planning maintenance activities or diversifying the tree stock in your community. There are several resources you can use to complete an inventory - paid staff, consultants and even volunteers. Many of us are aware of staff resources and consultants that are available to complete the project but few of us are aware of what volunteers might be able to do for us. Others may have assumptions about volunteers capabilities (we’ll have to show them everything), costs (they’re free, right?), and motivation (will they show up after the first day?). Before starting on a project, there are several questions you will want to ask. • What type of inventory do you want to complete, just a count or something more detailed? • How many variables do you want to collect on each tree? • What is your timeline? • What are your financial resources to complete the project? Perhaps you have already used volunteers on planting projects. If you take the time to get to

know them better, you will find they have many more skills than planting, mulching or caring for community parks. These same volunteers might have a background in anything from computers to plant science, to statistics and more. With some training, volunteers can not only complete your tree inventory but can become supporters and ambassadors for your program. Here are some points to consider as you weigh the pros and cons between a professional inventory versus one with volunteers. The following questions will help you decide if a volunteer inventory is right for your community: 1. How much time do you have to complete your inventory? If you are on a tight deadline, you will want to consider if volunteers are a practical option. Remember volunteers do have family emergencies, vacations, and maybe a job or school. 2. What about liability? Talk to your city’s attorney. 3. How detailed do you want your inventory? The amount of detail you need may be the first thing to consider. More detail means more data and this likely means more time to complete. Do you just want species name and diameter, or are you looking for details in many categories such as hazard tree assessment and tree health. More detail may require a significant increase in the amount of time in training. If you need significant detail, a professional might be a better option for your project. 4.What base knowledge do you want volunteers to have? Consider if you want volunteers to walk onto the project knowing their tree identification or how to use different types of equipment such as computer or PDA.

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5. How much training will volunteers need? When using volunteers, you will have to devote staff time and/or hire someone to do training. A study done in Minneapolis quantified many of the resources a volunteer inventory needs. (http://www.fs.fed.us/psw/programs/cufr/products/ cufr_660_MinneapolisCaseStudy_12-05.pdf). My own experience shows it will take a minimum of 12 hours of training to educate volunteers on tree ID and tree characteristics. So using skilled volunteers with a background in tree ID will cut down the amount of training time. 6. Do you want a consistent group of volunteers? Consider the minimum number of hours to complete the project. Weigh the amount of training needed compared to the amount of time the trainees will put into the project. If, from time to time, you are rotating new groups of volunteers into the project, it will take more of your time, versus a dedicated, consistent group for the whole project. Also, different people will view situations a little differently, so consistency is something to think about. 7. How many people should be recruited? First, estimate the number of trees that can be done in a day. As a rule of thumb, start with 1-2 minutes per tree. But remember, more detail means more time per tree. Include in your estimate data collection time, breaks, conversations with curious neighbors and travel. Second, estimate the number of trees you wish to include in your project. Finally, determine the size of each individual group. Two people in a group is typical. (It can be done with one person but someone new to tree ID will need someone to bounce ideas off, and safety is also important.) Are there additional volunteer needs outside of data collection? (Volunteer coordinator, onsite media relations, data compilation, etc.)

during data collection. There will always be questions. Someone may be needed to field phone calls from the media or interested citizens. 9. What type of resources will you provide? Think about what they will need for this job from start to finish. Will they need their own vehicle to get to the sites? Who will provide printing and copying, diameter tapes, handheld PDA, clipboard, GPS or other data collection device? 10. How will the data be compiled? How long will that take and who is responsible? If you use technology (PDA or computer) this will speed up the process of combining the data. If you collect data on paper, you will need a volunteer or staff person to enter all of the data into the computer. 11. How will you thank your volunteers? Your community has committed your time and its resources in completing the inventory. But your volunteers have given of themselves. Thank them for their contribution to the project. Their experience must be a positive one. These are just some of the questions that you will want to consider before you decide whether a volunteer based inventory is right for your community. Volunteers are great assets to your community forestry programs. Even though they are not paid staff, volunteers do require your time and resources. But by giving their own time and talents, they become more invested as the project progresses. They can truly be ambassadors for your program, the forest and your community long after the inventory is complete. Gail Nozal is the Assistant General Manager and Steve Nicholson is a Project Manager. Both work for S&S Tree Specialists.

8. Does the project manager have the time to devote to working with the project volunteers? Remember the project will need to be set up from start to finish. The project manager will be available for recruiting, training, site supervision and

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hazard

URBAN FOREST HEALTH

risk

Tree hazard and risk While most of us think of trees as valuable amenities in our communities that increase the quality of our lives, aging trees in populated areas also represent potential hazards. As long-lived plants, trees tend to accumulate, over time, a variety of defects that affect their structural integrity. These defects include decay, cracks, cankers, root problems, and poor architecture such as unstable branch unions. Trees with such defects can be hazards in the landscape, with the potential to cause injury or property damage. But do all trees with defects that affect structural integrity actually represent unacceptable risks in the landscape? Knowledge of tree structure and the defects that can compromise that structure, along with a familiarity with the concepts of hazard and risk, can help us to answer that question.

Definitions of hazard and risk Over time, the definitions of risk and hazard have been refined, the concepts have diverged, and most people now agree that they are different, though related, terms. A hazard exists when there is some condition that poses a threat to life, health or property. For trees, the hazard is potential until structural failure actually occurs. Tree assessors must take into account the severity of any structural defects and the probability of failure when rating trees for hazard. But there is another component that must be considered as well: the concept of risk, which takes into account not only the hazard, but the likelihood that harm will actually occur if a tree does fail. Large trees, being relatively dense, heavy, and prone to occasionally dropping branches or toppling over, obviously constitute hazards in the landscape. The hazard exists regardless of where the tree is growing, but the risk is dependent both on the probability that the tree will fail and the likelihood that it will strike something important: a target. Typically, a target is defined to include a person or a breakable piece of property that is exposed to the hazard. For the purpos-

By Joseph G. O’Brien

es of tree risk management, the nature of the target can greatly affect the actual risk represented by a defective tree. For example, a tree in a farm field, with numerous structural defects that make it likely that the tree will drop branches in the near future, constitutes much less risk to people or property than a similar tree growing in a school playground. In both cases, the hazard exists, but the actual risk of personal injury or property damage is much less for the tree in the farm field. Based on the explanation of terms above, we can construct the shorthand expression: Risk = Hazard + Exposure. Risk may range from low to high, depending upon the nature of the hazard, and the level of exposure of people or property to that hazard. Hazards can be minor to severe depending, for example, on the size of the tree part that may fail. Exposure is the likelihood that if a tree failure occurs, it will result in actual harm, either to people or property. In the example above, exposure to hazard is much higher when a defective tree is in a playground rather than in a farm field. Historically, a tree with defects that significantly affect structural integrity (indicating likely failure), which also has a valuable target, has been called a “hazard tree,” a term that implicitly incorporates both the concepts of hazard and risk. Trees with minor defects, or those with more severe defects, but unlikely to strike something valuable if they fail, are still low-risk hazards, but probably should not be referred to as “hazard trees.” Identifying these low-risk trees and recognizing that there must be some tolerance for risk in order to retain trees in the landscape are important considerations in any tree risk management program. Other terms such as “risk tree,” and “danger tree” have also been used to designate trees that represent an unacceptable risk of causing property damage or personal injury. The term “risk tree” is synonymous with the more commonly used “hazard tree.” “Danger tree” is a term used by OSHA (the Occupational Safety and Health

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Administration) to identify “a standing tree that presents a hazard to employees due to conditions such as, but not limited to, deterioration or physical damage to the root system, trunk, stem or limbs, and the direction and lean of the tree.” This term is most often used to refer to defective trees that may be a danger to workers such as loggers and arborists in the course of their jobs.

there is no likely target. There are alternatives to tree removal to mitigate hazard and risk. Many hazardous defects can be corrected, either by pruning or through the use of cabling and bracing techniques to reduce the likelihood or harmful effects of tree failure. Risk can also be mitigated by reducing exposure, for example, by moving a picnic table away from a hazard tree.

Tree risk assessment and management

Effective tree risk assessment should involve welltrained individuals who can identify the nature and severity of tree defects, and determine a reasonable estimate of the probability of failure. Tree risk assessors are usually asked to consider the likelihood that a tree will fail before the next inspection. Assessors must also evaluate the consequences of failure. These two factors, probability of failure (hazard) and consequences of failure (target exposure), are often used as the basis for a numerical or categorical risk rating of a particular tree/situation, which is used to assign priorities to mitigaPhoto: Joseph G. O’Brien tion activities, such A large tree always represents some level In this situation, the hazard is the large branch of this silver maple that is as pruning or tree (barely!) attached to a decaying stub. The risk posed by this tree is the high removal. Some hazard of hazard because of likelihood of failure, and the high probability that it will strike a valuable tree assessment its stature and limittarget. In this case, cars parked on the street, a moving vehicle, or even a systems also take into ed lifetime—all trees pedestrian are likely targets. account the size of the will eventually fail tree part that is most likely to fail in developing unless they are removed. A tree represents an a numerical risk rating. Most tree risk assessment unacceptable risk when it is both likely to fail, protocols (see Pokorny 2003 or Matheny & Clark and is also likely, upon failure, to cause person1994) provide guidance on defect severity and al injury or property damage. Not all trees with probability of failure, as well as assigning categostructural defects represent unacceptable risks in ries of risk for different situations. the landscape, and trees with identifiable defects may be retained in some situations. Many trees Individuals can be taught to identify the nature have defects that are unlikely to increase the likeand severity of hazardous tree defects, given proplihood of failure significantly (e.g., internal stem er training, but many people find it difficult to be decay within safe limits), and some trees with objective concerning the level of risk represented more severe defects are unlikely to cause personal by a defective tree. Because trees have considerinjury or property damage if they do fail, because At the tactical level in a tree risk assessment and management program, trees are individually evaluated for defect and hazard, and situations involving these trees are evaluated for risk. Tree risk assessment involves determining the nature and severity of the hazard, the likelihood that an adverse event will happen, and the consequences that may arise if the event does happen. As part of a tree risk management program, a tree risk assessment should also include recommendations for any needed mitigation measures.

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Photo credit: Joseph G. O’Brien

The hazard in this situation was the restricted root system of this large American elm. The risk posed by this tree was the probability that the tree did not have sufficient anchorage in its growing location between the sidewalk and the street to survive a windstorm, and the relative certainty that it would strike a target. In this case, the house was struck, but vehicles on the street and pedestrians were also possible targets. able amenity value in the landscape, some individuals are hesitant to remove defective trees that, by commonly accepted criteria, pose a significant risk for harm. Others who are highly risk-averse worry that retaining trees with known defects of any kind in the landscape leaves them open to liability. The job of a tree risk assessor is to balance the desire to retain trees in a natural condition with the knowledge that defective trees can represent truly unacceptable, high-risk hazards. Trained individuals who rely on conservative application of professional judgment will be able to make these judgments confidently, with the knowledge that risk cannot be totally eliminated in outdoor settings. The process for managing risk for trees in urban areas should follow an outline similar to this: • Assess trees for hazardous defects, and estimate probability of failure • Assess each situation for targets and consequences of failure (personal injury or property damage) • Based on an assessment of the hazard and target issues, establish risk ratings for trees by using training, professional judgment and, where available, published, objective criteria • Take action (prune, remove, brace, etc.) to mitigate the highest risk situations first • Ensure that all unacceptable risks are mitigated • Periodically reassess trees for hazard and risk, especially after severe storms

Hazard and risk are critical concepts for arborists, parks and recreation staff, utility workers and recreation site managers to know. The ability to identify “hazard trees,” defined as having a high probability of failure coupled with the likelihood of an adverse outcome, is an important skill for anyone who works with trees. For more detailed information on tree risk assessment, see Matheny and Clark (1994) or Pokorny (2003).

References: CPL 02-01-045 - Citation Guidance Related to Tree Care and Tree Removal Operations. http:// www.osha.gov/OshDoc/Directive_pdf/CPL_0201-045.pdf last accessed: 21 Jan 2009 Matheny, N.P.; Clark, J.R. 1994. A photographic guide to the evaluation of hazard trees in urban areas, 2nd edition. 85 pp. Pokorny, J.D. (coordinating author). 2003. Urban tree risk management: A community guide to program design and implementation. 194 pp. Full text available online at: http://na.fs.fed.us/pubs/ detail.cfm?id=1070 Joseph G. O’Brien is with the U.S. Forest Service in St. Paul, Minnesota. He can be reached at 651-649-5266 or jobrien@fs.fed.us

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The Case For A Street Tree Master Plan By Ken Simons Down through the ages, the roadside planting of trees has mirrored the order, prosperity and achievements of civilized societies. Man-made row plantings of uniformly spaced trees have testified to man’s presence, power and ability to organize his surroundings and influence the environment for his comfort, safety and visual pleasure. Row plantings of trees are one of the earliest and simplest expressions of an intentional and functional design. The “greening” of towns and cities, also known at times as “reforestation” and “beautification”, has long been pursued in this country, reaching definable peaks in the mid to late 1800s during the era of Andrew Jackson Downing and Frederick Law Olmsted, following the Dutch elm disease epidemic of the 1960’s and 1970’s, and as part of the current ascent of urban forestry. The importance of urban greening is supported by recent research and study that verifies the social, economic and environmental benefits of urban trees. Unquestionably, the urban forest contributes to a community’s quality of life. Together with public parks and open space, street trees are a primary component of urban greening. Primarily, streets serve as transportation and utility corridors. Street trees are an ancillary use and should be regarded as guests within these corridors. As such, decision makers must strive to ensure that street trees will not become unwelcomed intruders. Unfortunately, many street tree planting efforts have not been guided by a thoughtful master plan. All too often, in a rush to qualify for government grants, reforest denuded streets or maintain momentum of volunteer interest, street tree planting initiatives are the ill-considered result of a haphazard process influenced by uniformed biases without concern for after-care needs. Without a thoughtful master plan, trees that should be long term assets can become costly liabilities. Street trees are an integral part of a community’s infrastructure, and as such, warrant thoughtful

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planning and budgeted management. Some decision makers have not learned from past mistakes, and are the reason negative history repeats itself. For example, in many cities where Dutch elm disease devastated miles and miles of streets that were graced by Gothic-arching elms, decision makers have replanted those barren streets with miles and miles of green ash, Norway maple or autumn blaze maple. In effect, one monoculture tree population was replaced by another. Familiarity, popularity, adaptability and availability of certain species clouded judgements. Today, the threat of emerald ash borer, Asian long hornedbeetle and ash yellows causes city foresters to view the future of these replacement ash populations with great anxiety. Regardless of concerted education endeavors by utility companies, decision makers continue to place tall-growing trees under overhead utility wires, creating potential service disruptions and making such trees candidates for disfigurement by line clearance pruning. Like-minded short sighted decisions also result in the placement of trees in dedicated border areas and limited groundspace locations that, over time, bring the trees into conflict with road improvement projects (e.g. widening) and adjacent hardscape infrastructure (e.g. curbing, sidewalks, paths and underground utilities). Another common error often made by decision makers is the planting of intolerant tree species in unsuitable growing environments that, over time, contribute to abnormal growth, decline or mortality. In order to prevent such negative history from repeating itself, decision makers need to recognize and understand the relevant lessons of the past. If street tree initiatives are to fulfill the good intentions of decision makers, the right tree needs to be planted in the right place for the right reason and afforded the right after-care. This is the ongoing challenge that confronts decision makers. A thoughtful master plan that incorporates intelligent designs derived through a systematic comprehensive planning process is the road decision makers need to follow to accomplish their worthy objective. Ken Simons is a retired landscape architect and consulting arborist. This article has been extracted from a planning manual titled “The Road to a Thoughtful Street Tree Master Plan” .

Five Steps to Keeping Trees and Woodlands:

he 5-Step Program to saving trees during construction of homes in wooded areas was introduced in the Fall 2008 issue of the Minnesota Shade Tree Advocate, followed by a closer examination of steps 1 and 2 in the Winter 2009 issue. In this issue, step 3 is discussed in more detail.

Step 3: Stop the damage, not the construction. • Spend some time with the blueprints. Review the grading, utility installation and construction plans and the proximity of the activities to the significant trees. • Predict the likely damage that could occur due to those activities. • Lessen or eliminate the damage. Don’t stop construction, just alter the practices or construction plans when possible. • Hire subcontractors with reputations of successfully building around trees. Learn how to read blueprints or hire a tree care consultant that can read and interpret blueprints. Blueprints and site plans forecast damage long before it occurs and therefore offer the chance to prevent that damage. In particular, determine the following: • How close will excavation activities be to the significant trees (those trees worthy of saving)? • Where will the driveways, sidewalks and patios be located in relation to the significant trees? • Which utilities will be buried, where are the points of origin for the utilities and where will they enter the structure? • What grade changes are planned, either cutting or filling operations? • Will there be a necessity to store equipment or materials, provide parking for the contractors, or store waste materials during the construction project?

Step 3

By Gary Johnson

Destined to Fail Predisposed trees are “energy-weak” and are more likely to die or suffer more damage from normal stresses such as short-term dry spells or long, cold winters and are often more likely to contract certain diseases and suffer from insect pests. Anything that reduces the ability of the trees to photosynthesize normally and store energy reserves for normal growth and recovery from damage predisposes them to other problems. If the soil becomes irreparably compacted from heavy equipment or vehicles driving randomly throughout the building site, a long-term health problem for any trees with their roots growing in the area is created. Clayey soils are more likely to become permanently compacted than sandy soils. Moist soils are more likely to suffer from compaction than dry or frozen soils. When soils become severely compacted, roots only grow with great difficulty. Less water and fewer minerals reach those roots, and the trees become severely stressed.

Shallow or Deep, Excavations can Kill. Whether the excavations are wide and shallow, as in base preparations for driveways and sidewalks, or deep and narrow, as with burying utility lines, the root systems of nearby trees suffer. Shallow excavations tend to remove the fine roots and the trees’ ability to absorb water and nutrients. Deeper excavations remove the supportive branch roots in addition to the life-supporting fine roots. All the well-intended tree preservation plans can be for naught if a randomly dug utility trench comes within a few feet of a significant tree. A 2-4 foot deep utility trench will effectively remove all of the branch roots on at least one side of a tree, rendering it much less stable than before the incident.

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Even the relatively shallow excavations for driveways, sidewalks and patios have the potential to inflict one-time or long-term damage to the root systems of nearby trees. Unless the property owner is willing to live with a paved surface that heaves and settles like a roller-coaster as it freezes and thaws each winter and spring, some excavation and compaction is inevitable. Depending on how stable the soil profile is, there may be a need for deep excavation and compaction of the subsoil and base for the paved surfaces. If the paved surfaces are within the protected root zones* of the trees, some degree of damage is inevitable. Along with the damage to the soil that the tree roots are dependent upon, there can be physical removal of the tree roots during the process. Most tree roots grow within the top 3 feet of the soil. Specifically, fine roots –those roots that absorb over 90% of the water and nutrients essential for tree health – are located within a few inches of the soil surface. *You can calculate the protected root zone, that area of absolutely essential roots, by measuring the width of the tree trunk approximately 4.5 feet above ground. For each inch of trunk width, measure out 1 to 1.5 feet away from the stem of the tree and consider this area as the area to protect at all costs. One foot for 1 inch of trunk width for healthy and young trees, 1.5 feet per inch for older or weaker trees.

Please Replace When Finished Grade changes often involve “filling” as well as “cutting.” Filling over root systems, that is the addition of soil to level out a landscape grade, is more damaging than excavations that cut away the landscape grade. Soil that is added over root systems restricts the amount of oxygen and water reaching the fine root system, elements that are absolutely essential for plant life. As with cutting, filling becomes more damaging with the depth of fill and the texture of the fill soil. Fine textured soils such as clays and silts tend to cause more root death regardless of depth than sandy or organic soils. Many tree species can tolerate 1-2 inches of fill and recover nicely over time, but only a few can live long lives when 12 or more inches of fill soil entombs their root systems. If the excavation plans for the area include removing all topsoil before foundations are dug,

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that highly organic and productive soil could end up mixed with other soil layers, buried deep in the landscape or worse, removed from the site. That topsoil is the source of almost all of the beneficial soil microorganisms and nutrients essential for tree growth. Nutrient stresses commonly follow construction activities where the relatively shallow topsoil has been removed or highly altered.

Park it out Back! Finally, some of the most innocent activities can cause long-term damage to the woodland soil and root systems of trees. Parking vehicles, storing construction materials, and driving small equipment over the protected root zones of trees is at least as damaging as operating large equipment over the landscape. Any of these activities includes placing lots of weight on fragile soils, and if the soils contain a lot of clay, once they’re compacted they stay compacted.

some of the most innocent activities can cause long-term damage to the woodland soil and root systems of trees Cleaning constructing equipment over the root systems of significant trees offers a whole new way for trees to die slowly…chemical pollution. Concrete truck chutes, mortar and plaster boxes present an opportunity for the tidy construction worker to alter the pH of the soil for many, many years. These chemicals can drastically elevate soil pH, changing an acidic (sour) soil to a very alkaline (sweet) soil in literally a few minutes. When this equipment is rinsed out with water and then dumped into the root zone of significant trees, one can only hope that the trees growing in an acidic soil are also tolerant of big changes. Sometimes, that happens. Acid-loving trees often suffer severe nutrient deficiencies when the soil becomes more alkaline. Although these changes rarely if ever directly kill the trees, they predispose the trees to other problems by reducing their ability to photosynthesize normally and store up those necessary energy reserves that every tree needs to survive life’s daily challenges.

Changes that Make a Difference. 1. Separate, store and replace the soil layers in order. If the topsoil must be removed for excavation and construction, store it separately. When the activities are done and the landscape is put back in order, replace that topsoil where it’s meant to be…on the top of the landscape soil. 2. Consolidate utility lines. Don’t install four utility lines for four utilities, put them in common trenches. This isn’t always possible, but it’s almost always possible. Anything less than four trenches is a victory. 3. Don’t dig utility line trenches, “blow-out” the trenches! Not with explosives, but with high-pressure air excavation tools. This technology is now very common and completely harmless to roots. Most full-service tree care companies have this equipment and the ability to “dig” most of the utility trenches when they approach the protected root zones of trees. The jets of air blow away the soil from the roots and up to several feet deep into the ground. The utilities can then be installed (not water or sewer) under the root systems without causing any damage. 4. Apply for variances, move driveway locations and building pads to save significant trees. Don’t be bashful; if a variance would allow the building footprint to be relocated to a less harmful distance from the significant trees, apply for it. If a driveway can be moved from one side to another and still get the vehicles in the garage, move it. Not many things on a blueprint are sacred.

5. If filling or extensive grade cutting is necessary, build a retaining wall at the protected root zone distance of the significant trees. Retaining walls built three feet from tree trunks save tree trunks, but they don’t do a thing for roots. Beyond the retaining wall, do as much cutting and filling as you want. 6. Only use excavated areas for parking, driving, storing and cleaning. The driveway, sidewalk, patio and building footprint are all lost causes in terms of soil and root preservation, so they might as well serve multiple purposes. Anything beyond these excavated areas is protected land. If more parking and storage space is needed, choose areas away from the protected root zones. 7. Don’t build patios or sidewalks that require excavation if it will kill tree roots. Build boardwalks or elevated patios and sidewalks. It’s not the paved surface that kills tree roots, it’s the excavation. It may not be the originally designed patio surface, but it may be one that the trees and the homeowner can live with. 8. Go with good reputations. Find sub-contractors (grading, utility installation, hardscape installation) that have a reputation for successfully working around trees without killing them. Don’t take their word for it; follow up with their references. 9. Be ugly and monitor the whole project constantly. This is the time to micromanage! Gary Johnson is an Extension Professor, Department of Forest Resources, University of Minnesota.

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Photo: Karl Mueller

City of St. Paul... continued from pg. 1

Forestry

Environmental Services

The Forestry section is already benefitting from this new alignment. In recent months, we have expanded our volunteer opportunities and increased our community education and outreach efforts. Forestry has been in collaboration with the University of Minnesota to provide new opportunities for urban forest research, studentdirected studies, and training to NRU staff. Last November, we created the City of Saint Paul Tree Advisory Panel (TAP).

The Environmental Services program manages the natural resources and native areas in Saint Paul’s parks. In 2008, through a unique partnership with the National Park Service, our staff helped coordinate events for more than 1,600 Volunteers In Parks (V.I.P.) volunteers who provided over 3,600 hours of service. These service hours are the equivalent of one and three-quarters full-time employees (FTE) working in our parks!

The TAP’s proposed mission statement is to serve as a link between the Forestry section and the citizens of Saint Paul to preserve, promote, and enhance our urban forest. The fourteen-member TAP holds monthly meetings to assist the NRU with community event planning, they review and advise on city policy, and the development of new approaches to public engagement and education – especially for youth. The TAP consists of Saint Paul residents and professional volunteers who will help the city make an immediate and positive impact on our urban forest.

Our staff is also working hard to align the NRU’s volunteer programs with Mayor Coleman’s youthbased initiatives. Our ultimate goal is to engage at-risk youth in natural resources related activities in disadvantaged Saint Paul neighborhoods. We are excited to simultaneously address the needs of our community and our parks. In total, Environmental Services staff worked with over 3,250 individual volunteers in 2008 for a staggering FTE of five employees!

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Arts and Gardens The Arts and Gardens (A&G) program provides the backbone of the Blooming Saint Paul Program (BSP). This Blooming program is a comprehensive initiative to revitalize Saint Paul’s urban environment by incorporating aesthetic and environmental landscape elements in order to enhance the working, living, and tourism environment of the city. It focuses on creating an attractive, safe and healthy city where people choose to work, live and play. The A&G program maintains 130,000 square feet of garden beds, over 100 planters, and coordinates the city’s Hanging Basket Program, which includes more than 500 baskets. In an effort to

engage our city’s youth, the A&G program has created the BSP Horticulture Academy summer employment program, providing green industryspecific basic job skills. Spring is sooner recognized by plants than by men. ~Chinese Proverb Karl Mueller is an ISA Certified Arborist for the City of St. Paul Department of Parks and Recreation. He can be reached at karl.mueller@ci.stpaul.mn.us Adam Robbins has been the environmental coordinator for Parks and Recreation for four years. He has been working in the Twin Cities in the field of natural resources for more than twelve years. Adam Robbins can be contacted at adam.robbins@ci.stpaul.mn.us

Upcoming Events Saturday, May 16th & Sunday, May 17th – The 5th annual Festival of Trees will be held at Indian Mounds Regional Park. Events will include a tree climbing championship, bucket rides, kid’s climb, and other family-related activities. Free event for the entire family.

Want to volunteer in one of Saint Paul’s natural areas or gardens? Call 651-632-2459 or email environment@ci.stpaul.mn or visit our website at www.stpaul.gov/parks/environment for more information.

Mystery Tree Answer: Tamarack or Eastern larch (Larix laricina)

Spring 2009 • ADVOCATE

STAC INFO & NEWS

About MnSTAC The Minnesota Shade Tree Advisory Committee (MnSTAC) was established in 1974 by a group of concerned citizens to address the health and well being of community forests. MnSTAC is recognized throughout Minnesota and the country for its expertise, advice, coordination and support for community trees. It is an organization of diverse individuals who represent a broad spectrum of tree-related interests. It fosters and supports local community tree programs across the state so healthy community forests are fully integrated into community development, infrastructure, education and management. MnSTAC Board of Directors Katie Himanga President Steve Nicholson Vice President, Private Consultants – S&S Tree Steven Shimek MN Dept. of Agriculture Tina Markeson MN Dept. of Transportation Alan Ek University of Minnesota Dave Epperly MN DNR Forestry Jeffrey Gillman Univ. of MN Extension Service Glen Hambleton Tree Care Advisor Kit Richardson Local Tree Board Member – Minneapolis Don Mueller MN Society of Arboriculture Steve Roos American Society of Landscape Architects Dave Kleinhuizen MN Nursery & Landscape Assoc. Barb Spears MN Forestry Association Anne Oldakowski Soil and Water Conservation Districts Craig Johnson League of MN Cities Emily Barbeau City Forester–City of Minnetonka Kameron Kytonen City Forester–City of Andover Dave Auchter Utilities–East Central Power Deborah Karasov Non-profits–Great River Greening John Ingleman MN Corporation–Hutchinson Technologies Stephen Schott Student–University of Minnesota Ron Norenberg Citizen–DNR Region 1 – Park Rapids James Lemmerman Citizen–DNR Region 2 – Duluth Dave Moehnke Citizen–DNR Region 3 – Rochester Jill Johnson US Forest Service

Meet A MnSTAC Board Member – Kameron Kytonen I work for the City of Andover as the Natural Resources Technician. I’ve been married for five and a half years and have an eight year old son. I enjoy fishing, hunting and many sports including basketball, tennis and golf. I am a MnSTAC Board Member because I want to help make a difference for the organization and for this field. There are a lot of important issues in urban and community forestry that need attention, and MnSTAC has the knowledge and expertise to rise to the challenge. Being a part of this group is also a great chance to collaborate and network with others in similar professions and learn about some of the latest research and innovations. One passion I have is the concept of utilizing native, low-maintenance plant material including trees, shrubs, grasses and forbs for landscapes. There is a need to plant these in our communities to help restore, improve wildlife habitat, increase diversity, conserve groundwater, improve storm water quality and help improve regional character. I also think it’s especially important to increase the diversity of native trees in our landscapes, which will help prevent future devastating outbreaks of insects and diseases.

Calendar Events

May 21, 2009, New Tree Inspector Training, St Paul, Minnesota. Contact Rebecca Koetter at 612-624-4261. July 24-29, 2009, International Society of Arboriculture Conference and Trade Show, Providence, Rhode Island. www.isa-arbor.org

September 30-October 4, 2009, Society of American Foresters National Convention, Orlando, Florida www.safnet.org November 5-7, 2009, Tree Care Industry (TCI) Expo Trade Show and Conference, Baltimore, Maryland. www.treecareindustry.org

For handy up-to-date links to Web sites of interest, be sure to visit

www.mnstac.org

ADVOCATE • Spring 2009

Presorted Standard U.S. Postage PAID Permit No. 171 St. Paul, MN

Minnesota Shade Tree Advocate 500 Lafayette Road St. Paul, MN 55155-4044 RETURN SERVICE REQUESTED

Minnesota Shade Tree Advocate A quarterly newsletter published by the Minnesota Shade Tree Advisory Committee. Managing Editorial Group: (Emily Barbeau, James Burks, Ken Holman, Gary R. Johnson, Rebecca Koetter, Karl Mueller, Lara Newberger, Jacob Ryg, Stephen Schott, Mark Stennes, and Patrick Weicherding) Editor-in-Chief: Judy Slater Design: Creative Services Unit, MNDNR Material in this newsletter is not copyrighted. Reproduction for educational purposes is encouraged. Subscriptions are free. Articles, news items, photos and videos are welcome. This publication was produced with the support of the USDA Forest Service, Northeastern Area; State and Private Forestry.

Celebrate Arbor Month May is Arbor Month in Minnesota and Arbor Day, Friday, April 24, marks the beginning of an entire month of celebrating trees.

For Arbor Month 2009, the Minnesota Department of Natural Resources has developed a poster that promotes interacting with trees titled “My Favorite Tree Is …” The idea behind this year’s Arbor Month theme is to connect people with their favorite tree and the outdoors. We encourage everyone to create a photo, drawing, or story about their favorite tree and post it to www.mndnr.gov/arbormonth.

Address inquiries to: Minnesota DNR Division of Forestry 500 Lafayette Road St. Paul, MN 55155 Printed on recycled paper using soy-based inks. Spring 2009 • ADVOCATE