by Mike Faher
The map showing the extent of the emerald ash borer infestation in Vermont — so far — looks like something an epidemiologist would prepare to show the spread of a dangerous disease.
Reachable via a link from the Vermont Invasives website, the map features two ominous-looking red circles, overlapping along Route 14 in Barre and East Montpelier.
Highlighted are 11 towns, in Orange, Washington and Caledonia counties, that are within five miles of “confirmed infested areas.” There is a swath of orange depicting “high risk areas” where the infestation is “likely expanding into.” Or it already has happened, and all that remains is to locate the evidence of disease.
Emerald ash borer, first detected in February, in the town of Orange, then in Plainfield and Groton, has now been found in Barre and Montpelier.
The beetle, referred to by its initials EAB in the pest world, eats through the inner bark of the ash tree, depriving the tree of water and nutrients, effectively strangling it. Trees infested by the borer are usually dead within three to five years.
Once the presence of the beetle was confirmed by the federal Animal and Plant Health Inspection Service, the branch of the USDA that manages national pest outbreaks, it was inevitable that a quarantine would be put in place. The question was whether it would be on a county-by-county basis, or statewide.
Vermont recently opted for a statewide quarantine, meaning ash wood cannot be moved out of the state to Maine, Rhode Island or five counties in New Hampshire where EAB has not been detected yet.
“We’re focusing our limited resources on slowing the spread outside of those four towns where we know there’s infestation,” said Steven Sinclair, director of forests for the Vermont Department of Forests, Parks and Recreation. He added that the presence of the borer in the states surrounding Vermont means it likely will be found beyond the Central Vermont region.
Vermont municipalities have had varying responses to EAB so far.
Following the discovery of EAB infestation near the National Life complex, the city of Montpelier launched an assessment of its ash trees, focusing on those that could fall on sidewalks or roads in the most traveled parts of the city.
City tree warden Geoff Beyer said the city has trained volunteers to conduct initial health assessments of ash trees in the “higher risk areas.” If a tree were to show signs of infestation, branch samples would be taken for confirmation.
For now, the city’s plan is to remove infected trees but leave healthy ones. “If you wait too long,” Beyer said, “it becomes more dangerous and more expensive to remove a tree.”
It is believed that ash borer kills 99 percent of the trees, Beyer said, but there is always a chance that some trees would have a natural resistance. It would be a shame to act too fast, and remove a tree that might prove resistant, he said.
Sinclair described Montpelier’s approach as “aggressive” but added that “when you first start seeing evidence of EAB, it’s too late.”
Meanwhile the town of Williston, more than 30 miles from the closest known emerald ash infestation, has already started removing its ash trees. More than 40 percent of street trees in Williston are one of the three ash species in Vermont, so the town’s conservation commission was concerned about the safety and financial impact from the inevitable arrival of EAB, said the commission’s Melinda Scott.
“We’re looking at a pretty devastating impact in a short period of time,” said Scott, who commented that some streets in Williston are planted exclusively with ash. “Rather than having to come up with a huge amount of money all at once to replace dead ash trees, the town’s approach has been to replace them over time so the budget won’t be impacted.”
The town has gotten grants through the state’s community and urban forestry program for the past couple years to remove ash trees and plant a greater variety of species, including maple and elm. The idea of diversifying is to reduce the devastation should another pest prove fatal to any of its tree species, she said.
With regard to forest industries and to forest landowners, the state has advocated a cautious approach. About 5 percent of the trees in Vermont forests are ash, and their lumber is valuable, Sinclair said.
To landowners with ash forests, Sinclair says: “Don’t get ahead of yourself and remove healthy ash trees that could have commercial value.”
State officials encourage the public to report suspected beetle infestations online at vtinvasives.org/reporting-emerald-ash-borer.