Arlington Heights could lose one-third of its parkway trees to the emerald ash borer in the next five to seven years, public works director Scott Shirley told the village board Monday night.
The village has 13,080 ash trees on parkways, according to a report from the public works department, and 36,192 total parkway trees. Including trees that have been cut down as a preventive measure, the emerald ash borer is responsible for the demise about 25 million ash trees in North America.
While the Illinois Department of Agriculture says some treatments could be 80 percent effective, Shirley was skeptical.
"I don't know how much of that is emotional pressure to find a solution and how much is real data," he said. "People want an option to try to save their trees. And we don't have long-term information. We could treat trees for five years at great expense, then they could die anyway."
The board approved spending $20,000 to remove trees, including 177 ash trees in the Cedar Glen subdivision east of Arlington Heights Road and north of Algonquin Road. It's an area where the infestation has progressed so far that removal is the only option, a report from the public works department said.
But trustees balked at allocating funds to replace the trees in that area until a general policy is developed. Currently the village pays for replacing all parkway trees that are removed. A policy is necessary so all neighborhoods are treated fairly, Trustee Tom Hayes said.
Shirley said if the board decides to treat trees, the best option would probably be encouraging homeowners to treat the trees on their parkways. In the Surrey Ridge neighborhood the homeowners association paid to treat 130 ash trees this summer, the report said.
Answering questions from trustees, Dru Sabetello, village forester, said he is not sure how toxic the chemicals would be to the environment and people. He would choose a treatment that is injected into trees if the village decides to use chemicals.
Parkway trees are probably not a good option for wasps that are believed to help control the borer, said Sabetello, although it is possible the village could be chosen for that treatment.
Treating all the trees chemically would cost $1.6 million annually, said the report. Removing all the ash trees would cost $6.4 million, replanting new ones another $5.1 million if each tree is replaced, and restoring the sites another $425,100.
Sabetello said his main concern is that any trees that are lost be replaced with a variety of tree species.
The emerald ash borer was first identified in the U.S. in 2002 near Detroit and has spread to 15 states and Canada. In Illinois, the emerald ash borer has been identified in 20 counties and about 200 communities, according to the Illinois Department of Agriculture.
A village survey shows 73 percent of the trees in Greenbriar, a northern subdivision, are ash, as are 64 percent in Burr Oak and 63 percent in Northgate. Terramere and Northgate II/Lake Arlington have 59 percent ash and Surrey Ridge 58 percent. The total is 52 percent in Ivy Hill and the Courts of Russetwood.