Janesville committee listens to city's foliage
A Norway maple on Fremont Street appears healthy to the average eye. Bare branches are few. Its leaves are green, and it has plenty of them.
But look closely.
A split in its trunk never closed completely, and the wood there is soft. Moisture and insects have taken advantage, eating away at the innards. A girdling root—one that circles too close to the trunk—pokes out of the lawn, and that root feels spongy, too.
It probably will die a slow death, said Cliff Englert, Janesville parks department supervisor.
A green ash a few houses down is on the “watch” list for the emerald ash borer, a destructive Asian beetle that’s poised to strike Wisconsin. But it’s a vigorous tree with good-quality wood and leaves. It will be fine—unless the beetle gets it.
Those are just a couple of stories the Janesville Shade Tree Advisory Committee wants to share through its inventory of street trees.
An urban forestry grant is funding the effort.
Up to a dozen volunteers help with the inventory, which started in September. They stroll through random neighborhoods with a map, tape measure and hand-held computer, measuring trees and jotting down their species, location on the terrace, quality of wood and leaves, wire conflicts, sidewalk damage and maintenance needs.
That doesn’t mean every tree will be poked and prodded—just a representative sample of about 5 percent. So if Janesville has about 100,000 street trees, the committee will catalog about 5,000.
The final report will give a snapshot of the quality of the urban forest and how it can be improved.
Spurring the effort is the relentless march of the emerald ash borer, which could creep into Janesville from northern Illinois. The beetle can wreak millions of dollars in damage because infected ash trees and those nearby must be removed.
The inventory will help determine about how many ash trees Janesville has.
It also will show the need for diversity in the city’s tree population, which is dominated by ash, maples, honey locust, little leaf linden and Callery pear.
“We can’t make a lot of judgments and plans if we don’t know what we have,” said Englert, who is the shade tree committee’s secretary/treasurer.
The inventory “has always been an objective of the organization,” he said. “The fact that the emerald ash borer is around the corner makes it more timely.”
Englert said the average 70-foot ash tree is worth $1,100 and would cost $700 to remove.
“So you’re talking about a loss of $1,800 per tree,” he said.
The vigorous ash tree on Fremont Street is a source of pride for the homeowner, who came outside to talk with Englert and Mary Thompson, the committee’s president, as they surveyed trees on a recent chilly afternoon.
The man remembered planting the sapling 15 years ago.
“Most people are very interested in trees,” Thompson said. “People love their trees.”
Maintaining street trees is the homeowners’ responsibility, Englert said. The city requires that branches be pruned to 15 feet above street level and 7 feet above the sidewalk.
If a tree must be removed, that’s the homeowner’s responsibility, too.
So far, the committee hasn’t found many trees needing immediate removal, Englert said—just bad pruning jobs.
Englert intends to finish the inventory and report within the next two months. The report will include the estimated value of Janesville’s ash trees, so the city can see plainly what it has to lose.
Personally, Englert would like to see more Ginkgo biloba, an ancient tree that resists insects, salt and urban stressors. The city recently planted several of them in front of Hedberg Public Library.
The Janesville Shade Tree Advisory Committee offers resources on tree maintenance, planting and different varieties, including the best trees to plant in terraces. To learn more, visit the committee’s Web site at www.jstac.org.+
Last updated: 10:39 pm Thursday, December 13, 2012