Spring 2004 by Minnesota Shade Tree Advisory Committee

VOL. 6, NO. 2

Spring 2004

COMMUNITY PROFILE

PHOTO: ATLANTA BOTANICAL GARDEN

Tree Houses That Will “WOW” You

By Lorrie Stromme

y favorite movie as a kid was “Swiss Family Robinson.” I don’t recall the plot, but I vividly recall the incredible tree house where the family lived. It’s that kind of lasting impact that the Minnesota Landscape Arboretum is trying to create in its upcoming exhibition of 10 one-of-a-kind tree houses, called A tree house at the Atlanta Botanical Garden in 2003. A platform allowed people to have a Totally Terrific TreeHouses: Imaginative Places, “tree’s-eye” view. Ingenious Spaces. These tree houses have the  “WOW” factor. In December 2003, the Arboretum invited artists, architects, landscape architects, designers, contractors and builders to submit design concepts and proposals for tree houses. All designs had to be tree friendly—that means no nails, bolts, hooks, or anything that might girdle or rub the bark or damage the tree. A panel of judges reviewed the designs and selected 10 winners, each of 2 President’s Corner whom received a $2,500 stipend to offset construction costs. Winning designs 3 Urban Tree Risk Management can be found on the Arboretum’s web site, www.arboretum.umn.edu. The tree houses will be constructed on site in May. The exhibition, which runs from June 5 6 Clip & Save: Firewise Landscapes though October 10, is expected to attract over 100,000 visitors. A tree house on 8 Dispel-a-Myth: Nursery Practices and display at the Minneapolis Home & Garden Show in early February provided a Standards sneak preview of the exhibition. 11 After Ten Years of Oak Wilt The Arboretum regards this event as a celebration of trees. “Children will Management—Where are We? love the adventure,” says Arboretum Director, Peter Olin, “and adults will find 14 Mn/DOT’s PlantSelector plenty of reasons to visit the exhibit, from revisiting childhood to exploring new learning experiences and our beautiful gardens.”

Inside THIS ISSUE

Tree Houses continued on p. 2

Visit MnSTAC on the Web at www.mnstac.org

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 2004

Tree Houses from p. 1 PHOTO: HENNEPIN COUNTY HISTORY [MAGAZINE], WINTER 1964.

PRESIDENT’S CORNER

Looking Forward… to MnSTAC’s Future By Ken Simons For those who may not recognize my name, please allow me to introduce myself. I’m Ken Simons and I have the honor and pleasure of serving as MnSTAC’s new president. As a charter member of MnSTAC, I am one of the last active members from the 1974 assembly. With that in mind, it might be said that I am the keeper of MnSTAC’s history. While history in itself is very important, I need to function as MnSTAC’s leader for the next three years. This year, MnSTAC will celebrate its 30th birthday. It’s a time to be proud of our history and many accomplishments. It is also a time for me, as your president, to pause and consider MnSTAC’s current status. My task is to review MnSTAC’s involvement in projects, our partnerships with governmental agencies and nonprofit groups, our efforts to stimulate commitment and participation at the “grass roots” level, and our effectiveness to communicate our mission based message. The goal of my evaluation is to develop, with input from members and the Board of Directors, a three-year work plan for MnSTAC. This is not the time for MnSTAC to “rest on its laurels.” It is the time for MnSTAC to “put a new face” on longstanding issues and to champion new initiatives. We need to remind elected officials that the urban forest is an important component of the public infrastructure. We need to interact with urban forest councils in other states to glean new ideas. We need to partner with professional associations, corporations, schools, youth groups, and social organizations to help advance our commitment to the health, care and future of all community forests. Hopefully, each member or reader will commit some time and energy to MnSTAC’s future and/or the future of Minnesota’s urban forests. Since I’m semi-retired, I will commit at least 20 hours per week to work on MnSTAC’s mission. I hope you will join me, and find the time and opportunity to “speak for the trees.” I look forward to meeting and working with you!

MnSTAC welcomes Ken Simons as the new President. Ken is retired from the Ramsey County Park and Recreation Department after 31 years of service as a landscape architect. He continues his practice as a consulting arborist specializing in woody plant appraisals.

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Nearly a century ago, another Minnesota tree house attracted the attention of the media and the public. In this case, the tree house was more than a novelty. It was the yearround residence of Dr. Charles Dight, a Minneapolis alderman from 1914 to 1918. Dr. Dight built and occupied his “air bungalow,” located at 4816—39th Ave. S., near Minnehaha Creek in South Minneapolis. The 18 x 22-foot house was built on stilts about 10 feet off the ground. The front porch encircled a tree. Heating the tree house was problematic, so Dr. Dight wore boots and covered the floors with newspapers for insulation. Did I mention that Dr. Dight was a bachelor? Don’t go looking for the tree house today; it is no longer standing. MnSTAC is one of the sponsors of Totally Terrific TreeHouses. The Arboretum has invited MnSTAC to participate in the tree house event. It’s a perfect opportunity to educate exhibition visitors about trees, their benefits, and their care. If anyone is interested in helping out with an interpretive display or volunteering to answer tree questions for a few hours at the exhibit, please contact me at 612/788-5157 or stro0293@umn.edu.

If you go… Totally Terrific TreeHouses, June 5 through Oct. 10. Minnesota Landscape Arboretum, Chanhassen. 952/4431400, www.arboretum.umn.edu Lorrie Stromme is a past president of MnSTAC. She works for the City of Minneapolis.

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Establishing a Municipal Tree Risk Management Program By Mark T. Duntemann

very community forestry program should include a system for assessing, monitoring, and mitigating trees that pose a risk to the public. While trees that have been properly cared for throughout their life generally pose little safety concern, there is some risk associated with maintaining large-diameter, over-mature trees in public use areas. In rare instances, litigation may occur because of a tree or limb failure. If this were to happen, a community would have to demonstrate that they have implemented a reasonable tree risk management program. What is “reasonable” is a function of the resources available to a community. In other words, the level of care given to the trees in one community may not be reasonable for another because of limited staff, equipment, and/or budget. Risk is a function of how often one can expect an event to occur. There are two types of risk associated with trees a community must come to understand if it is to effectively manage the issue. There is the risk of physical harm to the

public from a tree or limb failure, and the financial risk to the municipality if a fatality, physical harm or property damage results from the failure. Municipalities minimize the financial risk by reducing the risk of physical harm from occurring. This is accomplished by enhancing the town’s tree maintenance and management regimes. There are two broad goals required of every tree risk program. They are: managing the tree resource for risk and documenting that the program is reasonable. The first goal establishes a community’s risk program. The second goal allows a community to defend their program if litigation occurs. Both goals are realized by initiating activities at two scales: the microscale and the macroscale. Microscale refers to activities centered on the care and assessment of individual trees. Macroscale refers to activities centered on managing the entire urban forest. The remaining narrative establishes a template for developing a municipal tree risk management program.

PHOTO: MINNESOTA DNR, MARK NEMETH

Tree Risk Management continued on p. 4

 ADVOCATE • Spring 2004

Tree Risk Management

G OA L 1

(Establish a Community Tree Risk Program)—Design and implement a program that identifies and mitigates over time the highest risk features in the tree population. Microscale Policies at the microscale for this goal promote activities that increase staff’s knowledge, skills, and experience evaluating and mitigating individual trees. The following tasks are clear outcomes for achieving this element of Goal 1. 1. Conduct or require repeated hazard tree assessment training for all staff that work on municipal trees. 2. Require staff to become International Society of Arboriculture (ISA) Certified Arborists. 3. Fund staff attendance to regional, state, and national arboriculture conferences.

Macroscale Activities at the macroscale for Goal 1 promote policies that allow the community to develop a reasonable program to manage risk for all trees they manage. There are five steps to defining the level of care appropriate for the community. These steps are: 1. Assess the Tree Population—The community should anticipate failures by reducing the most problematic features in the tree population. The tree inventory is the best tool for identifying these features. Risk increases when combinations of the following five items occur: problem species, large diameter, poor condition, structural defects, and high target. Establish simple criteria, using these five features, to identify the issues specific to the community. 2. Evaluate the Resources Available to Manage the Tree Population—Once the risk issues have been identified, assess what resources the community has to manage the risk. Assess available budget, equipment, and staffing levels. In addition to determining these resources, evaluate the community’s operational tree program.

3. Create A Risk Policy Statement—A strong policy statement identifies the overall mission of the community toward their high-risk trees. The tree risk policy statement must include the following: • State the community’s understanding of its responsibility to maintain safe public areas. • Identify the manager of the risk reduction program. • List any general constraints on managing hazard trees such as financial or personnel limitations. 4. Implement A Risk Management Plan—Once the first three tasks have been completed, a community develops and implements a risk management strategy. The strategy developed should address all issues identified at both the microscale and macroscale within Goal 1. The plan should articulate an objective and action plan for each issue identified. That portion of the tree population with the highest probability of failure must be the initial target of the management strategy designed. Subsequent strategies focus on creating achievable monitoring and maintenance of the entire urban forest. 5. Evaluate the Program—Staff should review whether the outcomes defined in the risk reduction plan are being met. If they are not being met, what changes have to occur to allow the outcomes to happen? In addition, staff should meet on an annual basis and discuss the significance of any tree failures from the previous year.

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Tree Risk Management

G OA L 2

(Defensible Program)—The community must be able to articulate the program developed. It forms the basis for defending the program. The easiest way to accomplish this goal is through documenting all of the outcomes in Goal 1 in a tree risk manual.

PHOTO: MN/DOT

Microscale Once a risk assessment program for individual trees has been established, the community documents that staff is fully qualified to assess, recommend and mitigate trees. For each employee: 1. List all arboricultural training courses attended for the year. Include the title of the course, the date, the duration, and any CEU credits obtained. 2. List any current certifications. Include the title, affiliation, date, and any CEU credits obtained. 3. List all conferences and workshops attended for the year. Include the title, location, date range, sessions attended, and any CEU credits obtained. 4. List all current professional association memberships.

Macroscale Having gone through the five steps for establishing a community-wide risk management program, document the outcomes from each of the five steps. 1. Summarize the assessment of the tree population. Summaries should include distributions for species, condition, diameter, and defects. The high target areas of the town should be mapped. Identify in writing all of the problem areas within the tree population.

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The overall focus of a tree risk management program is to identify those features of the tree population that pose the highest risk to the public, and then to concentrate the available resources on mitigating those features within an appropriate time line. By establishing a long-term risk reduction program and documenting it, a community defines a level of care that is both reasonable and defensible.

2. Summarize the resources available and current operational program. 3. Document the tree risk policy statement 4. Document all of the goals, objectives, and actions defined in the tree risk management plan. 5. Document the annual program review. Include the date of the meeting, minutes and outcomes.

ADVOCATE • Spring 2004

For further information see the illustrated training manual, Urban Tree Risk Management: A Community Guide, available free on CD or online at www.na.fs.fed.us/ spfo/pubs/uf/utrmm

Mark T. Duntemann, with Natural Path Urban Forestry Consultants, can be reached at natpath@earthlink.net

PHOTO: MINNESOTA DNR

Firewise Landscapes: Reducing Wildfire Risk to Woodland Homes By Tom Eiber and Dave Schuller 

s people move beyond the suburbs into the rural/urban interface, they are living in areas that have been shaped by wildfire. These wildfires are a basic component in the renewal of these lands. With homes in this fire-based landscape, homeowners put their homes at significant risk of destruction from wildfire. Most fire departments, trained and equipped to battle structure fires, are not able to protect the numerous, scattered homes threatened by a wildfire as it moves through an area. Recent wildfires illustrate the point here in Minnesota. In 2000, two separate wildfires just north of the Twin Cities destroyed eight homes built in wildland settings. Two more homes and a historic building were destroyed in 2002 near Brainerd. A home’s landscape adds beauty, value and functionality to a property. It also plays a critical role in determining the survivability of a home. Depending on how it is done, the landscape design and its maintenance can INCREASE OR DECREASE a home’s chance of survival. The technical issues are two-fold. A home needs to be nestled in a “defensible space” and “maintained.”

Create a Good Defensible Space A good defensible space around a home is critical for two reasons. It provides firefighters a place to work to protect a home and it reduces the chance that the wildfire can spread to and ignite the structure. There are three zones around a home that need to be considered to reduce the risk of wildfire loss.

Zone 1 is the structure zone, the area nearest the structure. If a wildfire (or burning embers) enters and ignites fuel in this zone, the home will likely be lost. This zone is 3-5 feet wide and extends under and around attached wooded decks. Rock mulch is a good ground cover. Plants are best kept out of this area. Juniper and other conifer shrubs MUST be removed from this zone. Zone 1 is compromised by any flammable material such as grass, stacked firewood, wooden walkways and fences that attach to the house. Zone 2 is the main defensible space and extends 30 feet from the structure. Wooden decks and sheds inside this zone are considered part of the structure and extend this zone accordingly, ie. 30 feet beyond the deck or shed as well as the house itself. This is the zone that, if properly landscaped and maintained, prevents the wildfire from reaching Zone 1 and the structure. It also gives firemen a place to work safely. If well constructed and maintained, fire entering this zone burns poorly with a reduced intensity. Zone 3 is a general fuel reduction zone. It extends 100 or more feet beyond Zone 2 into the surrounding wildland fuels. This is the area where excess fuel such as downed trees, tall grass, heavy brush, and dense conifer plantations generate the firebrands that can fly to and ignite the house. The objective in this zone is to reduce the intensity of an approaching wildfire as it nears the home.

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ILLUSTRATIONS: MINNESOTA DNR, JEAN MILLER

Defensible Space

Firewise Landscape Design Tips Zone 1 – Structure Zone – In this zone use non-flammable rock mulch or paving around the foundation and under decks. Favor block for retaining walls over wood or other flammable material. Ensure that there are no “wicks” that can carry fire to the structure. Wicks can be a wooden walkway from the driveway to the deck or house. A wooden fence that is attached to flammable siding is an excellent wick. It is better to keep the zone free of plants. Never stack firewood up against the structure. Zone 2 – Defensible Space – In this zone break up contiguous fuels with areas of well irrigated and short-mowed grass and use gravel & rock paving. These are your firebreaks. Butterfly gardens, evergreen trees and prairie patches should be created as small islands and kept separated from each other by grass or rock firebreaks. Trees in this zone should be well spaced and maintained so their crowns are kept spaced at least ten feet apart. Favor hardwoods over pines and other conifers and prune off lower branches, up six to ten feet,

Tree Spacing

but no more than 1⁄3 of the live crown. Brush piles and firewood must be excluded from Zone 2. Firewood stacks near the home are convenient in the winter, but should not be stacked before snow covers the ground and used or removed before the spring fire season. Zone 3 – Fuel Reduction Zone – If this zone is predominantly evergreens, its modification is critical. Consider removing some trees (thinning) so that the crowns of the remaining trees are at least ten feet apart. Prune the remaining trees up six to ten feet. Remove tall underbrush so that there is a space of six or more feet between the tops of the understory plants and the lower branches of the overstory trees. This reduces the “ladder fuels” that would allow a fire to climb into the tree crowns, starting an uncontrollable crown fire. The area southwest of the home is the most critical as our most dangerous wildfires generally approach from this direction. In these cases, consider extending Zone 3. Most of the embers that threaten to ignite a home are generated from this area. Extending thinning and pruning as much as 200 yards in pine stands will significantly reduce the risk of a home being exposed to intense firebrand showers. These treatments also greatly increase the chance that the pine stand itself may survive the wildfire by preventing a crown fire.

Firewise continued on p. 8

ADVOCATE • Spring 2004

Firewise from p. 7 Firewise Landscaping Plants There are no truly “fireproof” plants. Under the right conditions, all plants will burn. We commonly refer to those less susceptible to burning as Firewise Plants. Firewise Plants have the following characteristics:

• Remove leaf litter and dead vegetation from foundation plants and mulch. • Keep Zone 1 free of leaf litter. Remember, this includes areas under wooded decks. • Keep roof and gutters clear of leaves and other litter.

• Contain more moisture in their tissues, especially in spring and fall.

• Prune dead branches and thin trees as their crowns begin to touch.

• Have a low amount of volatile oils (most evergreens have high volatile oil sap).

• Remove annuals after they have gone to seed, or when the stems dry out.

• Accumulate less fuel by producing or catching less litter and stay small.

• Prune off the lower six to ten feet of branches from trees, but no more than a third of the tree’s height.

• Are compact and low to the ground. • Grow slowly, needing little maintenance such as pruning. • When exposed to drought, these plants commonly drop leaves and go dormant, have smaller leaves or very succulent leaves that store moisture. Generally, deciduous plants have more Firewise characteristics than evergreens. Also, when dormant, especially during Minnesota’s spring fire season, deciduous plants have less fuel to carry a fire. Juniper shrubs are NOT Firewise. In addition, plant a variety of native plants to help maintain vigor and health. Monotypes and exotics result in more insect and disease problems, resulting in more dead branches and plants, and are more fire prone. Mulch to reduce weed growth and conserve moisture. Avoid pine or cedar bark, pine needle mulch or other materials that easily catch fire. Wood chip mulch generally burns poorly with low intensity flames that are easily controlled. In limited amounts, it can be used in Zone 2. Do NOT use any flammable mulch in Zone 1.

Maintenance The best designed and developed landscape can be quickly compromised if not maintained. These routine tasks are often overlooked and can place a home at severe and complete risk should a fire approach. • Keep grass mowed. In Zone 2, to less than a 3-inch height and keep it well

watered. Under drought conditions, mow brown dry grass even shorter. In Zone 3, grass is best kept under 10 inches tall.

• Remove flammable materials around buildings such as firewood piles and lumber piles.

Landscape Business Opportunities Landscape architects, nursery sales staff, and landscape services have significant opportunities to increase business opportunities while providing a valuable service to your clients. Designers can look for opportunities to implement Firewise landscaping into the overall design, nursery sales can offer selections that improve home safety as well as beauty, and service providers can give good general maintenance as well as active mitigation as an additional service. Ask the customer if he lives in an area where pine and other conifers make up 40% or more of the general cover type. If so, they need to be Firewise.

Firewise communities Community foresters and other officials can help make their communities Firewise. Many Firewise practices such as thinning and pruning also improve tree health. There is both technical and financial assistance available to communities that want to become Firewise.

For More Information For more information visit the Minnesota DNR Firewise web site at www.dnr.state.mn.us/firewise, the national Firewise web site at www.firewise.org, or contact your local DNR Forestry office. Tom Eiber and Dave Schuller are with the Minnesota Department of Natural Resources Firewise Program.

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DISPEL-A-MYTH

Minnesota Growers and Landscapers: Have You No Standards? By Kelsey Hallcock and Gary R. Johnson

urely there must be some set of rules, some guidelines that all tree nurseries (retail and wholesale) and landscapers in Minnesota must abide by! Or, do we just hope that in the absence of such “laws” that people will do the right thing? As with most things, reality lies somewhere between the two extremes of total regulation and complete voluntary compliance. There are standards for nursery-grown trees and shrubs, albeit not unique to Minnesota. More importantly, there are some common “best management, best planting” practices in Minnesota. Four resources were consulted to create this expose: 1. The ANSI Z60.1, American Standards for Nursery Stock, standards that are recognized by the American Association of Nurserymen, Inc.; 2. Denny McNamara of Hoffman and McNamara Co. (growers and installers of trees and shrubs in Minnesota); 3. Tim Power of Law’s Nursery, Inc. (wholesale growers of trees in Minnesota); and 4. Tom Wawra of Bachman’s, Inc. (growers, retailers and landscape installers of trees/ shrubs in Minnesota).

There are no standards for growing, harvesting, retailing and installing nursery grown trees and shrubs that are unique to Minnesota. However, the ANSI Z60.1 standards are influential in Minnesota, and all contacts agreed that reputable “green industry” companies in Minnesota comply with these standards as a minimum. But what do the standards actually “guarantee,” if anything? Not nearly as much as you may suspect. As stated in its own words, the standards are a “communication tool,” attempting to make terminology consistent within the industry. What they don’t guarantee is overall plant quality or health. The standards were designed to establish some common techniques and language for measuring plants, determining the proper ADVOCATE • Spring 2004

relationship between the height and caliper or height and width of plants and determining whether a root ball or container is larger enough for a particular size plant. In Minnesota, the standards are a good start for most growers, retailers and installers. However, like our industry contacts, most green industry professionals feel that they are bare minimums… inadequately addressing many issues. The ANSI Standards for Nursery Stock are currently being revised and the issues of health and quality are being more seriously considered and defined. Another major reason for the revision is the increased production and sale of trees and shrubs in containers. Minnesota growers, retailers and installers acknowledge that this trend is also true for our state and their practices have been adjusted for the increased use of containerized nursery stock. How the different growers and installers operate beyond the standards falls under the definition of “practices.” Practices are not mandated laws or rules of operation. Rather, they are voluntary and are usually related to the most current research-based information available and the collective experiences of the growers and installers. Since they are not laws, practices cannot be enforced. However, knowledge of common practices is important to the consumer. If one knows what most professionals are doing in terms of best practices, one can judge the quality of the plants or work being provided to them.

DISPEL-A-MYTH continued on p. 10

DISPEL-A-MYTH from p. 9 So, what are the common “best practices” for growing and installing trees and shrubs in Minnesota? According to the experts we consulted, they are fairly consistent for the reputable nurseries and landscape companies, and very inconsistent with the others. Most growers, retailers and installers acknowledged that plants must be imported into the state to meet the demands, but all gave preference to local seed sources and stock. Tim Power (Law’s Nursery) maintains that locally grown stock, especially trees, tend to grow a bit slower through the production phase, but growers are usually rewarded with better developed branches and tree canopies. Most field grown nursery stock is mechanically harvested and the soil balls are placed in wire baskets lined with rot-proof burlap. The good growers and installers tend to avoid trees and shrubs tied up with synthetic twine, but acknowledge that it’s impossible to avoid it completely. Most installers have extended their planting season well into the autumn, and have found that there are certain trees that actually transplant and establish better when fall planted (e.g., crab apples, according to Denny McNamara of Hoffman and McNamara Co.). Planting holes are dug wide, 2-3 times the soil ball width or greater, especially when the planting soils are very compacted. All experts contacted felt that this extra effort at planting time was worth it due to the more rapid establishment of root systems. Depth of planting has become a critical issue. Everyone agreed that they do everything that they can to ensure the first branch roots are near the soil surface. At planting time, all twine is cut away from the tree stems, burlap and wire baskets are cut or rolled back for at least the top third of the basket…once the tree is safely in the planting hole and stabilized with some backfill soil. Trees and shrubs that were grown or finished in containers are automatically “root pruned” at planting time. As Tom Wawra (Bachman’s) recommended, four slices are cut into the root ball prior to planting to reduce the chances of plants suffering from pot-bound root systems. Some installers automatically amend planting soils with slow release nutrients (Bachman’s), and others add amendments (biostimulants, organic matter, gels) as needed/dictated by the condition of the planting site.

Kelsey Hallcock is an Undergraduate Research Assistant and Gary R. Johnson is a Professor at the University of Minnesota, Department of Forest Resources.

Everyone recommended mulching at planting time with 3-5 inches of coarse, organic mulch. All required their installation crews to pull the mulch away from the tree stems, sometimes to a distance of 6 inches. For the most part, staking was done on an “as-needed” basis. However, Bachman’s installation crews automatically stake container-grown trees for one season after they have been planted in the landscape. All companies contacted reflected the recommendations for watering new trees as expressed by Tom Wawra from Bachman’s: avoid blanket recommendations. Customize watering regimes based on soil type, time of year, size and species of plant. Finally, guarantees! Most reputable nurseries and landscape companies in Minnesota are flexible with their guarantees and acknowledge that one year guarantees are often inadequate. As a practice, these businesses stand by their plant materials when they know that the trees have been planted and maintained correctly, and are often quite generous with their guarantees. Much more generous than one year. The quality of their plants and their planting practices is their reputation, and you can’t buy a good reputation.

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URBAN FOREST HEALTH

After Ten Years of Oak Wilt Management, Where are We? By Susan Burks

he year 2002 marked 10 years of active oak wilt (OW) management within the Minnesota Department of Natural Resources (MN DNR). Active management began with a federal pest suppression grant in 1992. In 1998, the effort was incorporated into a community assistance program called Minnesota Releaf. The Releaf Program broadened its scope, in 2003, to include other forest health practices in an attempt to integrate traditional urban forestry with ecosystem management at the community level. In the meantime, the status of oak wilt across the state had evolved as well. Early in the program, aggressive outreach enrolled a large number of communities. Their involvement increased legislative support, while at the same time, decreasing the incidence of OW, in spite of continued pressure from urban development. In 1997 and 1998, a series of spring windstorms across central Minnesota damaged large numbers of oaks at the height of the oak wilt infection period. As a result, numerous new OW infection centers sprang up across the area. In response to increasing disease pressures, requests for community OW funding exceeded available grant dollars for the first time in 20012002. As a result, a system of prioritization was needed to determine the level of community funding. However, developing a system that would withstand close scrutiny from the state legislature, participating communities and partner organizations proved to be a difficult task. On the program’s tenth anniversary, the change in program goals and the increasing need to upgrade the technologies used to collect, manage and interpret treatment data, prompted an evaluation of the Minnesota oak wilt program. A preliminary analysis of the existing data was completed in 2002. In 2003, a formal assessment of the status of OW in Minnesota was initiated with the support of both state and federal funds.

Early Oak Wilt Suppression The Minnesota effort began in the 1970’s with the research of Dr. David French, and reached program status in the late 1980’s with a formal survey done in 1988. Color infrared ADVOCATE • Spring 2004

photography (CIR) was taken of Anoka, Ramsey and Washington Counties plus parts of Isanti, Sherburne and Chisago Counties. Dakota Count and scattered areas in southeastern Minnesota were added in later years. A massive outreach effort was launched by a coalition of the University, government agencies, industry professionals and concerned individuals to inform landowners and garner public and legislative support for disease management. The slogan ‘Don’t Prune in April, May and June’ was advertised across the state and soon most Minnesota residents in the affected area had heard of oak wilt and its potential to kill trees. In 1992, the MN DNR was awarded a $500,000 pest suppression grant from the US Forest Service and the first costshare program (CSP) was launched. The overall goal was to lower the incidence of oak wilt to levels manageable by local units of government and thus build local capacity to sustain long-term community forest health. Based on research that described the average rate of spread and satellite infection development, the density of oak wilt manageable by local government was determined to be one infection pocket per square mile. The control zone was defined as the six county area known to contain the most oak wilt. Dakota County was added to the list the following year. The original project objectives were to reduce the incidence of oak wilt within 75% of this control zone to one active infection center per square mile and to do so within five years (by 1997) through active community assistance. In the initial survey, 3006 infection pockets were identified in 44 townships. By the end of the federal cost-share program in 1997, 8387 infection centers had been identified across an expanded control zone of 79 townships. Participating communities had treated 5164 infection pockets or 61.5% of the known pockets. Even though the original survey data indicated that the density was nearly twice as high as expected, the cost-share program lowered the density of oak wilt from 2.97 centers per square mile to 1.58. Within 53% of the control zone, the density was lowered to one infection center or less. Given the high initial density, this is a significant accomplishment. Oak Wilt continued on p. 12

Oak Wilt from p. 11

MINNESOTA DNR

The other significant program accomplishment was the high level of public awareness and involvement achieved. During the five years of the first federal suppression project (’92-97), communities and private citizens spent more than 3 million dollars to match 1.95 million dollars in federal funds, for a project total close to 5 million dollars!

Minnesota Releaf

Treatment Summary Research has shown that the most reliable method of controlling below ground spread is through the use of root graft disruption using a vibratory plow blade. The most reliable method of controlling overland spread is removing all potential spore-producing trees (those showing oak wilt symptoms). Fungicide injections work well to protect individual trees from infection, but are not adequate to protect neighboring trees not receiving treatment. A combination of root graft disruption and potential spore producing tree removal is critical in protecting the long-term health of Minnesota’s oak resource. In reporting oak wilt management activities, sites were considered ‘treated’ if they had received any combination of treatments or if it were determined (by the community) that no treatment was necessary (i.e. further disease spread was no longer possible). Communities reported vibratory plow (VP) treatments alone on 25% of the treated sites and potential spore producing tree removal (PSP) alone on 42% of the sites. Only 16% of the sites received both VP and PSP treatments. Besides the high number of sites receiving only VP or PSP treatments, the data pointed out that a large number of sites were being treated over multiple years. Past research had indicated that treatment success after one plowing averaged between 93-97%. Yet 20% of the sites within the combined CSP and Releaf programs had received treatments over multiple years, suggesting treat-

MINNESOTA DNR

In 1998, the state incorporated oak wilt management into the Minnesota Releaf program. Since then funding has been uncertain with funds available some years and not others. Intermittent and/or delayed funding has impacted the level of management activities and in a few cases, community participation. Yet public support has remained high as demonstrated by the number of letters and testimonies given in support of state budget requests during the ‘02-03 legislative session.

Since the 1997 and 1998 wind storms, the incidence of oak wilt has increased and the increase has reversed previous gains in several areas, particularly in Sherburne County; hit the hardest by the storm events. In response to increasing questions about program success and necessary funding, the data was exported to Arc/ View and for the first time the treatment history for each site was assessed.

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ment had not been a success the first time. Some sites had been revisited as many as nine times. Once the treatment data became available, a number of new questions arose. Correlations between disease incidence and differences in local program implementation began to become apparent. While the trends described in the data help program managers understand where problems may exist in state program delivery, they couldn’t be used to redesign the program to meet changing needs due to the methods used to collect the data. Yet, the increase in disease incidence (and decreasing resources with which to control it) meant program adaptations were needed. But based on what?

2003-2005 Oak Wilt Assessment A formal reassessment of the status of oak wilt in the state was initiated in 2002. New CIR photography was taken of 33 townships with another 76 townships flown in 2003. The data will be used to establish a baseline for the current federal CSP and to analyze the change in disease incidence based on a variety of factors. The primary goal is to evaluate our current management strategy; is it working at a program level and if not, why not. A secondary goal is to describe factors outside our control (like urban development and storm damage) and the influence they are having on disease incidence so we can incorporate that information into the way we prioritize treatments (and cost-sharing). While the details are still being discussed, the assessment project will be divided into two stages. The first involves interpretation and digitization of all new CIR to establish a baseline. Digital orthorectified quad (DOQ) maps will replace the 1:24,000 K maps as the base layer. That will allow finer detail in the interpretations. The work will be done in Arc/View to avoid data distorts that can occur during translation to other formats. The second stage will take data from the new CIR and run a comparison against existing CIR data to describe the change in disease incidence, i.e. density per square mile. Noted changes will be assessed by three factors; type of oak wilt control program, change in urban development, and presence/absence of storm damage resulting from the 1997 or 1998 storms (where that data exists). All of the new CIR photography has been taken. Photo interpretation is under way. A minimum of 5% of the mapped pockets will be ground truthed by the state, i.e. field checked, during 2004 to establish the accuracy of the photo interpretation. Change detection and analysis will occur during the fall of ‘04. The final results will be available spring 2005, at which time Releaf management strategies will be reevaluated and modified as needed. ADVOCATE • Spring 2004

For those participating in the Releaf program, that means that the management strategies, mapping protocols and the system of prioritization for funding will stay the same for the next year. That timing should work well since 2005 marks the beginning of the end of the current Releaf grant and the beginning of the new biennium.

In the meantime… With the continuing increase in disease incidence, one of the biggest questions we face is whether or not it is possible to stay ahead of the spread of oak wilt. While some communities are doing an excellent job of staying current, others are falling behind. Modifying the means of program delivery and enhancing resident outreach may be all that’s needed in some cases. Better enforcement of PSP removal, for example, is one area where improvements can be made. But in other areas, disease incidence seems to be increasing in spite of well-run, full-service programs. Whether or not our strategies are inadequate, or outside factors are having a stronger influence, these areas serve as a source of continued disease pressure that may eventually overwhelm those that currently have oak wilt under control. Those with the worst problem are tempted to throw up their hands because of the effort and expense involved in slowing the spread of oak wilt. However, continued management is critical to the oak resource as a whole. If those with the worst problem quit now, neighboring areas will be overrun. It is easy to focus only on those trees in your own back yard. But if we are to succeed, it is important that we all work together to preserve Minnesota’s oak resource. Susan Burks is a Forest Health Specialist with the Minnesota Department of Natural Resources.

A new resource for community foresters is the compact disk: “OAK WILT: People & Trees, A Community Approach to Management.” To request a free copy of the CD, visit the “Knowledge Store” at the US Forest Service, http://ncrs.fs.fed.us/pubs/ or call 651/649-5244.

COMMUNITY RESOURCES

Mn/DOT—We do more than just build roads! By Scott Bradley and Todd Carroll

1. Improper selection and location of plant species within challenging and disturbed roadside environments has been a widespread problem which results in costly failures, erosion of public and stakeholder support, and the potential for safety hazards. PHOTO: MN/DOT

Scott Bradley and Todd Carroll are Landscape Architects at the Minnesota Department of Transportation.

itting around this winter, staring out at the cold snowy days, my mind tends to wander towards spring and planting season. As I look around my yard or as I sit at my desk at work, I start to get ideas about what I would like to plant. As of last fall, some of the decision process was made easier by the launching of Minnesota Department of Transportation’s (Mn/DOT’s) new PlantSelector web site. Now many of you might be saying “Mn/DOT, I thought they only built the roads.” Well, let me tell you the story behind the effort and why Mn/DOT came up with this program. Back in 1991, Mn/DOT Landscape Architects and Foresters began the research to develop some kind of “right plant—right place” plant selection expert system to try and remedy the following three problems:

2. While a wealth of landscape planting publications, reference materials and research was available, it was often inconsistent, incomplete or contradictory for our specific needs. 3. Many of Mn/DOT’s highway landscaping professionals had been held in high regard as “cutting edge” in knowledge, leadership and research for many decades, but when they left the organization, their knowledge went with them because we had no method to capture it, or to readily retrieve and utilize it if we had captured it.

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To make a long story short, we leveraged funding and collaborations in four separate phases of project development (from 1995 to date) resulting in three very successful plant selection “expert system” products and tools:

Phase 1 In 1995, Mn/DOT’s Metro Division provided us with $15,000 to complete a database, photo documentation and programming for development of a prototype plant selection “expert system” that could be utilized by Mn/DOT. The effort involved many volunteer collaborators and a paid programming consultant.

Phase 2 In 1996, Mn/DOT’s Office of Research Administration granted $8,500 in research implementation funding to enable us to further enhance, test and produce the prototype “expert system” including the production and distribution of 1,000 CD-ROMS entitled Trees & Shrubs for Minnesota Landscapes & Roadsides. Distribution began in the fall of 1996 in partnership with Mn/DNR Forestry who offered to capture public sales revenue for future project development.

Phase 3 In 1998, Mn/DOT’s Office of Research Administration granted another $13,625 in research implementation funding for us to dramatically expand and enhance the “expert system” including addition of four herbaceous plant material databases, more color photos, software updates and refinement of a more intuitive, and user-friendly presentation format. The expanded “expert system” on CD-ROM was entitled Woody & Herbaceous Plants for Minnesota Landscapes & Roadsides. After final testing and production, 1,000 CD-ROMs were made available for initial distribution and another 1,000 CD-ROMs were incorporated as part of the Catching the Snow with Living Snow Fences manual. By the fall of 2000, over 1600 copies of the new CD’s had been distributed or sold: The CD-ROM was free to Mn/DOT and collaborators, $35.00 for public sales. Over $10,000 of revenue had been generated and captured for future project development and numerous awards were rolling in including FHWA’s Environmental Excellence Award for Research. At that stage, the CD-ROM “expert system” correlated 49 distinct fields of information, 159 reference publications and 84 Mn/DOT continued on p. 16 Spring 2004• 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 President: Ken Simons—763/717-9366 Vice President: Michael Max, EnvironMentor Systems, Inc. —763/753-5505 Kimberly Thielen-Cremers, Minnesota Department of Agriculture— 651/296-6692 Jim Hermann, Mpls Park & Rec Board/Forestry—612/370-4900 Ken Holman, DNR/Forestry—651/296-9110 Fletcher Johnson, Xcel Energy—651/639-4590 Gary R. Johnson, U of M/Forest Resources—612/625-3765 Robert Slater, MN Dept. of Transportation —507/529-6145 Kirk Brown, Tree Trust—651/644-5800

Regional MnSTAC Committees Southeast STAC

Chair: Henry Sorensen—651/388-3625 or 651/385-3674 Sec./Treas.: Katie Himanga, Heartwood Forestry, Lake City —651/345-4976

Headwaters-Agassiz STAC (HASTAC) Chair: John Johnson, City Forester, City of Thief River Falls—218/681-1835 Sec./Treas.: Jeff Edmonds, DNR Forestry, Bemidji —218/755-2891

West Central STAC

Chair: Bob Fogel, Director of Parks, City of Moorhead —218/299-5340 Sec./Treas.: Dave Johnson, DNR Forestry, Detroit Lakes —218/847-1596

Northeast STAC

Chair: Kelly Morris, City Forester, City of Grand Rapids —218/326-7600 Secretary/Treasurer/Technical Advisor: Dan Jordan, IRRRA Mineland Reclamation—218/254-7967

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URBAN AND COMMUNITY FORESTRY

Calendar Events

New Publications

April 22, 2004 Building With Trees, St. Paul, Minnesota, www.arborday.org/phcseminar

Forest Policy for Private Forestry: Global and Regional Challenges. Lawrence Teeter, Benjamin Cashore, and Daowei Zhang. 2003. CABI Publishing.

April 23, 2004 NE Minnesota Community Forestry Workshop, Cloquet Forestry Center, Contact Ken Holman, 651/296-9110

The Land We Share: Private Property and the Common Good. Eric T. Freyfogle. 2003. Island Press.

April 24, 2004 St. Paul’s Festival of Trees, Como Park, Contact St. Paul Forestry 651/632-5129

Making Forest Policy Work. Alastair I. Fraser. 2003. Kluwer Academic Publishers.

June 5-18, 2004 Finland & Estonia International Study Tour, SAF International Forestry, Contact Dick Reid 317/894-0138 or reidconsulting@aol.com

Planting Nature: Trees and the Manipulation of Environmental Stewardship in America. Shaul Ephraim Cohen. 2004. University of California Press.

June 9-12, 2004 ABC of Arboriculture, European ISA Conference, Maastricht, Holland, www.ISA2004.nl

The Ecology and Silviculture of Oaks. Paul S. Johnson. 2002. CABI Publishing.

June 23-24, 2004 Stewards of Past and Future: Exploring Tools for Historic Preservation on Campus, University of Minnesota-Morris, Contact Nancy Erdahl at 320/589-6100 or erdahl@mrs.umn.edu June 28-30, 2004 Community Forestry at It’s Best National Conference, Nebraska City, Nebraska, www.arborday.org June 22-July 7, 2004 International Seminar on Watershed Management, Stevens Point, Wisconsin, Contact Karin Theophile 202/5015513 or ktheophile@fs.fed.us, www.fs.fed.us/global. July 31-August 4, 2004 American Phytopathological Society Annual Meeting, Anaheim, California, www.apsnet.org August 7-11, 2004 ISA Annual Conference & Trade Show, Pittsburgh, Pennsylvania, www.isa-arbor.com October 3-6, 2004 40th Annual Society of Municipal Arborists Conference & Trade Show, Denver, Colorado www.urbanforestry.com

Urban Tree Risk Management: A Community Guide to Program Design and Implementation. USDA Forest Service, www.na.fs.fed.us/ spfo/pubs/uf/utrmm/index.htm

Web Sites Forest Resource Environmental Education Network www.freenetwork.org Minnesota Arbor Month www.dnr.state.mn.us/ arbormonth The National Arbor Day Foundation www.arborday.org Tree Biology Dictionary www.treedictionary.com Woodland Advisor Program www.cnr.umn.edu/cfc/wa

Celebrate Trees! April 30 is Arbor Day and May is Arbor Month

Minnesota Shade Tree Advocate A quarterly newsletter published by the Minnesota Shade Tree Advisory Committee. Managing Editorial Group: MnSTAC Education Committee (Gary R. Johnson, Mark Stennes, Jeff Rick, Ken Holman, Patrick Weicherding and James Burks) Editor-in-Chief: Judy Slater judyslater@earthlink.net 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 U.S.D.A. Forest Service, Northeastern Area; State and Private Forestry. Address inquiries to: Judy Slater Minnesota Shade Tree Advocate 115 Green Hall 1530 Cleveland Ave. N. St. Paul, MN 55108 Printed on recycled paper using soy-based inks.

Mn/DOT from p. 14 professional and academic reviewers and collaborators for more than 650 species of trees, shrubs, vines, grasses, flowering forbs, sedges and ferns with over 2600 color photos. At the same time, we tried to document and measure tangible benefits using a survey questionnaire, which in a nutshell documented the following: • 82% of transportation-user respondents indicated use of the system improved their proficiency and consistency in making or reviewing plant selections appropriate to challenging needs and constraints.

a web-based application seemed to be the most logical approach for the present and future. In 2001, Mn/DOT’s Office of Research Administration granted $25,000 in research implementation funds to once again refine the system and totally “retool” it for migration to a web-based application. With programming assistance from a paid consultant, we completed initial development of the web-based PlantSelector system in 2002. Then Mn/DOT worked one year to finalize the system.

• 95% of transportation-user respondents indicated use of the system as an education/training tool expanded their knowledge or the knowledge of their clients and colleagues. • 92% of transportation-user respondents indicated use of the system saved them time and money. • The average time and cost savings per respondents = 55 hours and $1,957 annually.

Phase 4 Over time, we were running out of CD’s, and like many other older forms of software, our CD’s were not compatible with the new Microsoft Windows Xp operating system. At the same time, staff reorganizations and cutbacks at the Mn/DNR closed the door on their ability to continue providing CD marketing, sales and revenue capture in collaboration with Mn/DOT. Migrating to

Minnesota Shade Tree Advocate 115 Green Hall 1530 Cleveland Ave. N. St. Paul, MN 55108 RETURN SERVICE REQUESTED

The PlantSelector is now up and running at www.plantselector.dot.state.mn.us. As you browse through the program, we hope you will find it very comprehensive and easy to use. You may notice that some of the plants are missing photos or information. We view the program as a work in progress, which is different than the CD-ROM’s from the past. The positive thing about converting to a webbased program is the ability to modify or add new information as it becomes available. If you are interested in contributing to the program, please contact Mn/DOT at plantselector@dot. state.mn.us and let us know your thoughts. The warm, glorious planting days of spring are just around the corner. Hopefully, we can provide some information that helps you have a successful planting season.

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

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