• By Lisa Brody

Urban forestry: adding to the sense of place


As kids, many of us lay on our back on a bed of grass, staring up into a cluster of green leaves against a clear blue sky. As we get older, we appreciate the whole plethora of benefits that trees in our midst offer us, from shade on warm days to privacy from our neighbors to the beauty offered by tree-lined streets, and often seek to live in communities with lots of trees, parks and other natural amenities.

Our love and appreciation of trees are reflected by the iconic 1913 poem, Trees, by American poet Joyce Kilmer, who wrote the now-cliched lines, “I think I shall never see/ A poem as lovely as a tree.” While the inspiration for Kilmer’s poem has been debated, for individuals and communities, trees are often the gold standard for a community.

“Landscaping, especially trees, are part of what make cities the positive place they are. It’s an important thing that helps make an urban environment a place people want to live, work, play in,” said Mark Nickita, AIA, an architect, urban planner and president of Archive DS in Detroit and Toronto, as well as a Birmingham city commissioner. “Vegetation can have a huge impact – and lack of vegetation can have a huge impact – just like bad lighting in a cafe. People don’t always realize the importance of lighting, whether in a home, office or restaurant, and it can drive you away. Landscaping if very much the same thing. If you have the right mix, the right size, the right placement, it can make a city – and you know it when you see it.

“It’s what keeps drawing people to cities like Birmingham, Royal Oak, Huntington Woods and Pleasant Ridge,” he said of the mature, canopied and desirable cities along the Woodward corridor.

Many local communities have developed urban forest preservation plans, woodland ordinances, and tree preservation plans and ordinances as ways to either maintain the beauty and character of their municipalities, or to create and preserve that environment. Some municipalities determine tree policy for only a community’s public spaces, including public right-of-ways, and leave individual and neighborhood areas alone. Others manage policy for both private and public spaces, determining how many trees a developer or homeowner can remove and mandating tree replacement plans.

“About 80 percent of urban forestry is in the private realm – in your backyard, your neighbor’s backyard. The public realm is only about 20 percent, including right-of-ways, public properties, public parks,” noted Kevin Sayers, program coordinator, Urban and Community Forestry, Michigan Department of Natural Resources (DNR) Forest Resource Division. He said the program he administers at the DNR involves providing assistance to local units of government to help in the management of public trees. “But urban forestry is broader than that – urban forestry is wherever it is. That’s one of the riddles of what we do – how do we work across that to incentivize and grow appreciation of trees and the urban forest.”

Sayers said that municipal managers usually understand what is meant by “the urban forest,” which is considered a collection of trees that grow within city, town or suburb, and its care, but often don’t have all of the tools and resources to adequately maintain it in their community. Urban forestry experts emphasize that urban forests play an important role in the ecology of our human habitats, as they filter our air, water, sunlight and provide shelter to animals. Trees and urban forestry help to moderate local climates, slowing wind and stormwater, shading homes and businesses to conserve energy, and provide nesting sites and a home and food for birds and animals.

It’s hard to find a lot of negatives to saving and maintaining trees. Some researchers believe it can increase home values, and even decrease crime.

Lee Mueller, project developer/forest specialist, Davey Resource Group and chairman of the Michigan Urban and Community Forestry Council, concurs. “It’s hard to find a bad reason to have trees. We want to find reasons to incentivize ways to keep them,” he said.

Mueller said that some municipalities began developing urban forestry ordinances as long ago as the early 1880s, and continue to the present day.

“There was a lack of electricity and air conditioning, and there was a need for shade,” he explained. “Nationally, you’ll see the initial ordinances beginning in the late 1800s. In the northeastern states, there were tree warden ordinances, where you’d establish a tree warden to have some kind of determination. He would be established as an authority for the care of trees in a community. The industry was floundering at this point – it was just beginning. It was about, essentially, ‘we care about trees, we need someone who cares about trees to take care of them.’”

Mueller said the tree warden history in northeastern states “continues to this days, especially in Massachusetts – that’s one that comes to mind.”

Throughout the United States, a more up-to-date version of the tree warden is the label of Tree City USA, which was established in the late 1960s by the Arbor Day Foundation to provide direction, assistance, and national recognition to communities that work on tree preservation and urban forestry preservation maintenance and commensurate ordinances.

“It’s a framework for a healthy, sustainable urban forestry program in your town. And the benefits are substantial,” the Arbor Day Foundation said. “Many communities use the Tree City USA standards as a way to begin caring for city trees. Others regularly enhance urban forestry management through urban forest management through improved ordinances, innovative programs and increased emphasis on planting and care.”

Tree USA designations are “ubiquitous in Chicagoland,” Mueller said, “and are very strict and enforced. In Grand Rapids, they are strict, but in their surrounding areas, which are older communities, they may not reflect the changes in best practices. In metro Detroit, it’s really hit or miss. Some communities have them, and they’re really strong. Others have them and they’re not well known. Others don’t reflect current best practices.”

In Michigan, there are currently 111 communities that qualify for Tree City USA designation, including Auburn Hills, Berkley, Birmingham, Ferndale, Franklin, Huntington Woods, Milford, Novi, Oak Park, Rochester, Rochester Hills, Royal Oak, Southfield, S. Lyon, and Troy in Oakland County; Detroit; the Grosse Pointe’s; Charlevoix; E. Lansing; Dearborn and Dearborn Heights; Grand Rapids; Kalamazoo; and Marquette. Some cities have qualified with the requirements to receive the designation for decades; others are new participants. Birmingham, for example, has proudly been a Tree City USA for 39 years, Royal Oak for 40, and Rochester Hills for 27, while Rochester has participated for just four years and Franklin for 13.

“There are multiple benefits to having a Tree City USA designation, starting with the publicity. It’s a well-recognized brand that says this community is proactive in taking care of trees, they’re a good manager of trees,” Sayers of the DNR said. “It says a lot about the community. It’s a way to promote the community as a place to live, a place for businesses to be.”

“Trees are the green infrastructure of a community, and it is valued by the Birmingham community and provides for a positive impact with all aspects of living in the city,” noted Birmingham Director of Public Services Lauren Wood.

The Arbor Day Foundation asserted that among the benefits of urban forestry and the Tree City USA program are that it reduces costs for energy, stormwater management and erosion costs, as trees yield three to five times their cost in overall benefits to a city, and helps cut energy consumption by up to 25 percent. “Studies indicate that as few as three additional trees planted around each building in the United States could save $2 billion annually in energy costs,” the foundation states at arborday.org. Energy.org agreed, stating that carefully positioned trees around a house and on a property can reduce a household’s energy consumption for heating and cooling by up to 25 percent.

The European Environment Agency stated that in one year, a mature tree will absorb more than 48 pounds of carbon dioxide from the atmosphere, and in return, will release oxygen into the environment in exchange. An acre of mature trees can absorb the amount of carbon dioxide in a year that is emitted by a car driven 26,000 miles. A British research study at Lancaster University revealed that trees planted by local roadsides can reduce nearby indoor air pollution by more than 50 percent, which then improves air quality and human health.

“In Chicago, trees remove more than 18,000 tons of air pollution each year,” the U.S. Forest Service said – with one large tree capable of providing a day’s supply of oxygen for up to four people.

Further, properly placed trees can increase property values from 7 – 20 percent, as buildings in wooded areas sell and rent more quickly and tenants stay longer, the U.S. Forest Service stated.

Nickita agrees. “We see there are increased values of homes in more mature neighborhoods, with mature canopies of trees. A street with no trees is very different than a street with large trees with canopies or small trees. A new subdivision just built on former farmland, with just a bunch of small saplings – in 30, 40 years it will have something, but now, it’s relatively unpleasant. It’s part of why more mature neighborhoods are so in demand. It’s not just because of the mature homes, but because of the tree conditions, which contribute to the quality of those neighborhoods.”

Pete Auger, city manager for Novi, which became a city in only 1969, said their tree ordinance and forestry program, which evolved over time, helped to create a green canopy over the development that has grown with the city.

“All of our subdivisions have tree-lined streets, and it softens the edges around the developments. If you look at an aerial of the city, at a satellite version of the city, we have a very nice canopy throughout the city,” Auger noted, “not just in the public spaces, but in private spaces as well, which helps draw people to the community. I think what it does is it provides a greater human scale. There’s green just about everywhere in the city, and it’s connected. And the track record speaks for itself, with home values not just maintaining themselves but increasing in value.”

Trees and green spaces directly correlate to greater connections to neighbors, some asserted, as does the National Wildlife Federation, “Nature makes you nicer, enhancing social interactions, value for community and closer relationships.”

Urban forestry, with large yard and street trees, can even help communities and neighborhoods reduce crime as well as increasing a home’s value, according to Dr. Geoffrey Donovan, a research forester with the U.S. Forest Service in Portland, Oregon. “In my urban forestry research, I have estimated the impact of trees on house prices, rental prices, crime, energy use and birth outcomes. Further studies will focus on the effect of urban trees on public health and stormwater management.”

Studies Donovan has done show that “trees and other foliage can make a place look well cared for. It can project a sense of authority in that neighborhood,” he said. Large trees and street trees can provide the crime reduction benefits to residents on that street that people seek. In one study, Donovan looked at 431 crimes in Portland that were reported at 2,813 single family homes, and in general, found that trees in the public right-of-way were associated with lower crime rates, including burglary and vandalism.

“Trees may also draw people into public spaces, increasing the probability of a criminal being observed... We distinguished between trees in a house’s yard and street trees in the parking strip between the sidewalk and the street...Street trees tend to be farther from the house than yard trees. Second, street trees typically do not block the view of a house from the sidewalk,” Donovan wrote in The Effect of Trees on Crime in Portland, Oregon. “Therefore, if trees help a neighborhood appear well maintained, they may deter crime.

It also said that trees can affect a criminal’s state of mind because research shows that trees can reduce stress, and perhaps trees reduce crime “by reducing the stress of potential criminals. This could include stress lined to violent acts perpetrated by one member of a household against another.”

In cases where yards contained many small trees, or were unkept, vegetation may actually facilitate crime. Smaller trees can obstruct views, making it easier for criminals to hide and carry out their activities.

In another research paper, Donovan quantified the effect of front yard trees on the sales price of homes in Athens, Georgia, and found they added $422 – or 1.1 percent – to their sales price, and having a home with large trees on three sides of the home reduced the time the home would be on the market.

Within communities, trees have the ability to tame stormwater systems, allowing rain to refresh the land and nourish and nurture green spaces. “As houses, stores, schools, roads and parking lots spread and natural tree cover is lost, so is the absorbing effect of vegetation and soil. The welcoming rain becomes costly stormwater runoff,” according to arborday.org. “Without the benefit of trees and vegetated infrastructure, waterways are polluted as oils, heavy metal particles and other harmful substances are washed away. Fish and wildlife suffer, drinking water becomes expensive or impossible to reclaim, property values are reduced, and our living environment is degraded.”

Urban forests have been shown to also be an economic motivator, according to americanforests.org, which said their studies have shown that people walking or driving down a street lined with trees are willing to pay up to 12 percent more for goods and services, “and the presence of trees encourages patrons to spend a longer time shopping.”

A community with lots of well-maintained trees is generally considered beautiful and inviting.

“People see trees from an aesthetic perspective. They’re pleasing to the eye. Where there are no trees, people are put off, especially in suburban areas,” said Robin Boyle, professor of urban planning at Wayne State University. “Tree cover has great importance, and is good in a variety of ways, especially in the central city and suburbs. It provides shade for walkability – and cities are not walkable when they do not have shade. They provide great benefit to everyone, but especially seniors, because it’s good for our health to get people out of doors. The most important correlation to elder health is how much seniors get out and walk, and tree cover offers shade to offer walkability.

“The third thing is, today, it’s a justification for climate change,” Boyle continued. “They’re good for the environment. Trees offer a cooling element and great value to the environment.”

Urban forestry plans, woodland ordinances and tree preservation plans – rather than being a hindrance to development or personal property rights, are designed by most local communities as ways to offer cooperative management of individual trees, tree canopies, vegetation, and disease control.

“The very fact a community is thinking about having an ordinance, enacting them and having the conversation about an ordinance at all is indicative a community is being proactive,” DNR’s Sayer said. “Why they’re having the conversation is another story – maybe there has been clear cutting over development, changes in the ecosystem – you don’t know where the conversation came from.”

He noted that these kinds of ordinances shouldn’t be looked at as anti-development, which many communities agreed with, “because development is good for growth, but it’s important to protect landmark trees, and it’s a priority to protect ecosystems.”

Mueller, the forestry specialist, said that “In the private realm, they’re usually for community beautification. They’re part wetlands preservation, part beautification, part stormwater and air quality preservation. Depending on which path they went down, and which consultants they use, it determines which way the ordinances are written. Every community is different, but it’s important to find the best tools for every community, and it’s important to have the conversation. Tree ordinances are almost exclusively private. Individual ordinance provisions should reflect the uniqueness of the community and absolutely reflect the goals of that community. It’s great for a community to have these ordinances – but it’s important for each community to look at their own tools and needs.”

Birmingham is one municipality which focuses on public property, and not on private property. According to Lauren Wood, the city has two distinct documents, one, a tree preservation ordinance, which was enacted in 2003, and a tree management plan, prepared and implemented in 2012.

“The Tree Preservation Ordinance assists the city in protecting its city-owned trees and privately-owned trees adjacent to construction sites, giving the city the ability to promote and preserve the urban forest through established standards and requirements as spelled out in the ordinance,” said Wood.

“The Tree Management Plan is a tool used by the administration for short-term and long-term maintenance needs and tree planting initiatives,” she said. “This entailed a tree inventory conducted of public right-of-way street trees and the trees in the two municipal golf courses. A total of over 16,000 tree sites were recorded during this inventory. The software for this inventory is used and updated to manage and improve the city’s urban forest, and the data is used for continuing tree care in Birmingham. It aids in the preservation of the urban forest, improves public outreach and tree planting to mitigate removals and increase canopy cover.”

Canopy continuity and preservation – maintaining the beauty of the tree-lined street with trees that come together to form a canopy over neighborhood streets – is a major priority of the management plan, which notes that effort “will reduce stormwater runoff, improve air quality, promote public health, and enhance the aesthetic value of this resource.”

The management plan assessed the health of the city’s trees, noting which needed be removed (six percent); pruned (90 percent) and how many more needed to be planted (four percent). While several streets decades ago were planted with one species of tree, today, a variety are planted in order to avoid having them wiped out by disease or insects, such as Dutch Elm Disease or the Emerald Ash Borer.

“Species diversity is the variety and abundance of trees in a specific population,” Birmingham’s tree management plan stated. “It affects the population’s ability to sustain threats from invasive pests and diseases. It also impacts maintenance needs and costs, planting goals, and canopy continuity.”

Having a proactive approach is proving to be a beneficial one for Birmingham. Following the plan’s guidance, it states, “Proactive tree maintenance has many advantages over priority maintenance: the most significant advantage is reduced risk. When trees are assessed and pruned regularly in a proactive program, most defects will be found and eliminated before they escalate to a hazardous situation.”

Different municipalities follow different pathways. West Bloomfield Township was one of the first communities in the 1980s to enact a woodlands ordinance, covering both public and private property – which was then challenged by a developer in court in favor of the developer. “Our journey started with a definition of pure forestry, and it ran into a bump in 1989. It led us to clarifying our woodlands ordinance, which is an overlay district,” said Marshall Labadie, director of development for West Bloomfield, who noted the township has a woodlands ordinance – not a tree preservation ordinance – because they prefer to look at “the woodland system in its entirety from the ground up. We look at preservation of mature trees as well as the understory for the future. Everything in the boundary of the limits of that woodland is protected. To us, three acres defines a woodland.

“We’re suburban forestry in West Bloomfield,” Labadie continued. “We’re a bedroom community. We have tied all these subdivisions, platted lots and site condos together, their common areas, to create a suburban forest.”

The ordinance states its purpose is to “Provide for the protection of woodlands, including trees and associated forms of vegetation, as natural resources that contain elements of natural beauty, wildlife habitat and geological, hydrological, ecological and historical characteristics significant to the citizens of the township... Protect the township’s woodlands for their current and future value, not only for residential areas and home sites, but also as settings for development in all zoning districts;...to maintain plant and tree diversity; to protect groundwater recharge areas; to maintain visual screening, windbreak, dust collection and noise barrier characteristics exhibited by woodlands.”

Labadie said that the 1989 lawsuit forced them to clarify their definition of woodlands, which other municipalities have since gone to school on, following their lead.

“It (the original ordinance) was a little bit arbitrary. It didn’t define it by forestry standards – we were a bit obtuse. We had to put in a lot of definitions and standards, and it works great now,” Labadie said. “It goes to our environmental protections in West Bloomfield. We protect our environmental assets. It’s a main pillar. It’s very important to us, and we use it frequently.”

Nik Banda, Rochester assistant city manager, is also the city’s professional forester, having gone to Michigan Technological University in the 1970s to learn urban forestry. Early in his career, he worked with the city of Southfield to create a woodland tree preservation ordinance.