Choice of replacement trees complex
- Published: August 2, 2012
“The right tree for the right location” is a phrase oft repeated by arborists dispensing long-term landscaping advice. It was used several times last week by those focused on deciding how to replace the Bradford pear trees that line the downtown over the next few years. If the Village moves ahead with a plan to replace the trees, that group, including Village authorities, the Yellow Springs Tree Committee and several area arborists, will have to choose from a limited pool of trees with long-term viability in an abusive, urban Ohio setting. The ultimate goal is a net gain of trees in the downtown that will continue to provide shade and beauty for locals and visitors alike.
Village Council will continue a discussion on whether to replace the trees and their potential replacements at its next meeting Monday, Aug. 6, at 7 p.m. in Council chambers at the Bryan Center.
As part of its current sidewalk repair and downtown streetscape redesign, the Village is considering the removal of 14 pear trees mostly along the east side of Xenia Avenue and planting 17 trees of one or more different species evenly divided along both sides of the street. The pear trees were planted about 35 years ago, which, according to Tree Committee member Dan Beverly, is about three times the expected life span for a tree suffering the abuses these were subjected to, including compact tree pits, severe topping, constant traffic fumes, and unprotected bases. And when the Village buries the power lines under the sidewalks downtown along both sides of Xenia Avenue, the tree roots on the sidewalk side will be cut, further impacting their ability to survive.
“Even if you leave them in [after the sidewalk construction], you’re going to lose them in a year or two anyway,” said Wendi Van Buren, the Ohio Department of Natural Resources’ urban forester for Greene County. “When you dig around tree roots, it can stress the trees, and when that amount of stress happens to the roots, the tree won’t survive long term.”
By burying the lines, the Village intends to make way for a new set of trees that will have the space to grow as tall as nature intended them to get, Village Manager Laura Curliss has said. The question then becomes, should the Village move ahead with the streetscape plan, what are the right trees for this downtown location?
The right trees
The Bradford pears weren’t a bad choice for the location, according to local arborist Bob Moore, a wholesale distributor for Listerman & Associates. But recently Bradfords have been found to invade more native ecosystems and have been discouraged by public landscaping groups, including Van Buren’s. The discovery immediately brings up the possibility of replacing the pears with native species.
While natives are a good thing to strive for in theory, both Van Buren and Moore believe that most native species are accustomed to living in their natural forested environments with rich soils, plenty of space to spread their roots and enough water to feed their growth.
“You’re asking an incredible amount from a tree to handle the salt, drought, cars and heavy pruning — native sounds great, but if they can’t take the abuse, it’s not going to work,” Moore said. “We have great, beautiful, awesome native trees, which we can look at in the Glen. Sixteen [or so] trees downtown is not going to tip the balance of diversity with the trees in town.”
So what cultivators have done is create new species, grafted from their native cousins, that do have the hardy properties that allow them to survive tougher settings. But in addition to being tough, the current setting downtown also requires trees that will grow relatively quickly in a 5×5 foot tree pit (the bare minimum, according to Van Buren), which tends to limit the upper growth to a corresponding branch height of perhaps 25–45 feet. The trees should not create a mess of berry droppings downtown, but they should have deeper root systems that won’t impact the basements of the buildings less than 10 feet away. They need to be varieties that are available in the immediate area, so they can be dug and replanted with minimal exposure. And there should be a diversity of species to prevent a blight from wiping out the whole lot.
It’s a complicated process to narrow down the optimum trees, according to Roger Beal, who owns Yellow Springs Design and is the Village consultant for the current streetscape project. YS Design, which celebrates its 20th anniversary this year, drew the plans for the Dayton Street redesign in 2001 and handles commercial design projects across the country.
“Then there’s the installation process, which will be a very delicate operation,” Beal said. “What everyone has to realize is that whatever gets planted, if it’s not the right fit, it may need to be replaced.”
According to Van Buren, the Village has several categories to choose from, including the tough “junk yard dogs” that will live through anything, small “Chihuahuas” for placement under wires, and the “great Danes” that grow quite large and can canopy over the street.
“You always want to go as big as possible, for the shade and canopy that will give the community the socioeconomic benefits that it needs,” Van Buren said.
According to Moore, thornless honey locusts, for example, have done well in tight spaces with ascending branches (versus ones that spread out at right angles and could block traffic on the street side and damage buildings on the other). Male gingkos are a slower growing but tough species, as are berryless sweet gums or state street maples with yellow fall foliage, Moore said. Lace bark elms, columnar oaks and lindens are some possibilities Van Buren suggested. And the London planes and red spire pears, some of which the village already has downtown, are additional options, Beal said.
Public landscaping process
Currently the Village of Yellow Springs has no formal landscaping plan or standards to guide where and what to plant or how to install and maintain the existing greenery. And it’s largely thanks to the all-volunteer efforts of the Yellow Springs Tree Committee that over the past 30 years the village has seen an increase of about 2,000 trees on public properties.
“Our whole goal has been to plant as many trees as possible because they’re very valuable to the village,” Tree Committee President Anna Bellisari said this week.
According to long-time member Dan Beverly, the Tree Committee receives donations, often for memorial trees, and plants trees on public property wherever an open space will accommodate the requested variety. The committee waters and mulches the tree for three years until it is solidly established, and from that point on, it becomes the Village’s responsibility.
Many of those trees won’t need any attention at all for dozens of years. Such was true of the Bradford pears downtown. The Tree Committee chose the trees and cared for them for three years, and aside from the topping to clear the utility lines, the trees required little additional care, according to Beverly. Some do need to be trimmed near power lines and where they encroach on the right of way or get damaged in a storm. According to Village Manager Laura Curliss, the Village street crew manages much of the tree work with an annual budget of $10,000–$15,000.
But the informal relationship and relatively relaxed communication between the public and private groups has sometimes led to working at cross purposes. Recently the Tree Committee planted a tree near the Bryan Center tennis courts, a tree the Village later requested be removed for other plans. And sometimes the trees do need a little care, which if the Village hasn’t budgeted for or planned on managing, doesn’t always happen, according to Bellisari.
“The Village hasn’t always managed the trees because there is often not the budget or manpower to do it,” she said.
And Moore wonders if the Village’s lack of involvement in choosing or locating the trees it will later care for could put the trees at risk for shorter lives and leave the Village with less effective city planning.
From Curliss’s perspective, the relationship isn’t broken, but it could benefit from a little framing, such as building into the cost of the Tree Committee’s memorial trees the long-term maintenance fees that would help the Village care for them. Typically a tree might cost $500, half of which is to purchase the tree and the other half for its long-term maintenance. The Village might also have infrastructure knowledge and be able to guide the installation of trees in ways that increase their health and longevity, Curliss said.
According to Van Buren, Curliss “is a tree person” who has taken many of her extension courses and would be a good person to entrust with the public good of the trees. Curliss estimates she has personally planted about 500 trees, and in June she joined her crew to prune the zelcova trees on Dayton Street before Street Fair.
The Tree Committee has also recognized the wisdom of coordinating more closely with the Village and is working with Curliss to establish a working relationship and perhaps share some resources, such as the pickup truck the Tree Committee owns. Committee members also see that they are running out of public space to place trees, a place where the Village could help if, for example, an ordinance allowing the Village to plant trees on private property could be passed. The arrangement is one Curliss has read about and considered for Yellow Springs, as it allows the trees more space to grow and yet still can contribute to the canopy near the right of way. The Village would care for the tree, and the property owner would benefit from an extra tree in the yard.
“I’d like to work with the Tree Committee on a placement plan for trees in the future,” Curliss said. “We’re kinda getting planted out and the trees are starting to compete with the arts folks, the sports interests, and some who just want open space… it’s not just you, but everyone has ideas about how they want to use the public space.”
Other cities’ practices
Many cities have comprehensive public landscaping standards that the city of Toronto, for example, uses to protect its vegetation, increase the ecologically appropriate environment and reduce the long-term maintenance costs for its public infrastructure. Toronto’s Green Development Standard requires, for example, that new plantings include 50 percent drought resistant species and 50 percent native species, and that each street tree be given at least 30 cubic meters of high quality soil. The city of Alexandria, Va., has a set of tree planting standards 36 pages long that includes, for example, plant specifications, guidance on the use of invasive species, water management requirements, and project installation and maintenance procedures.
Curliss said this week that, while the Village was not likely to pursue that level of planting and development standards, it does aim for better communication between the different groups who are working on greening the village. Villagers could benefit, she said, from a coordinated effort to remove the ash trees that are expected to die within the next several years from infestation by the emerald ash borer. Some estimate the count in town to be just under 100 ashes, according to Bellisari. Curliss is interested in discussing how to replace all those trees, too.
As for the pears in Yellow Springs, new trees will come in at about 12 feet tall and within perhaps three years time will reach the current height of the pears, which are shorter than normal because of the topping, Curliss said. Whatever the choice, the new trees will add to the already leafy village and help to make an even greener downtown.
“The great thing about the village is it’s got a great urban forest, but it is an urban forest so it interacts with people quite a bit,” she said. “We’ve gotta make sure both get along.”