With spring approaching, Francestown is preparing to combat the invasive emerald ash borer, a beetle native to northeastern Asia that feeds on ash trees.
The beetles were discovered in town late last summer, Conservation Commission Chair Betsy Hardwick said, in an insect trap behind the horse barns in the center of town.
Emerald ash borers appeared in Concord in 2013 and have been spreading through the state ever since.
“They’re saying that if it’s here, it’s going to pretty much devastate the entire ash population,” Hardwick said.
The Conservation Commission and county forester had set the insect traps in early summer to monitor for the insects, Hardwick said, and Francestown residents received a letter in September alerting them to the beetles’ presence in the area.
Landowners are recommended to take down their ash trees or treat them with insecticide if the trees are in a place where they could cause damage if they fell, Hardwick said.
The beetles can kill a tree within three to five years of infesting it.
“Once they’re infested, they die quickly,” she said, and that ash trees become particularly brittle when they die, posing more of a hazard than some other tree species.
“We just cut eight trees down on my own property, they were all infested with ash borer,” she said.
The Conservation Commission had previously put together a list of public areas in town that had ash trees, she said.
Town Administrator Jamie Pike said the 2020 budget includes a few thousand dollars towards managing town-owned ash trees, but it’d be cost-prohibitive to take care of them all at once.
Andrea Grant, of Francestown-based Andrew Grant’s Tree Service, said that her business saw a noticeable uptick in calls about symptoms of infestations over the last year, and said they’ve taken down a few infected trees in town. Grant hasn’t observed anyone proactively taking down healthy trees yet, however.
“If there are no signs, most people want to keep the trees,” she said.
She expects ash-related calls to double once the season warms up.
Francestown and adjacent towns Antrim, Lyndeborough, Deering, and Weare are all listed as generally infested areas on a map maintained by the UNH Extension. That means the emerald ash borer is present, but not necessarily in all ash trees. Hancock, Bennington, Greenfield, Peterborough, Sharon, Temple, Wilton, New Ipswich, and Jaffrey are all in a “potential expansion area,” meaning that those areas are within 10 miles of known infestations, and there’s a high probability the insect will spread naturally to the zone within a few years.
An infected ash tree may present split bark, “D”-shaped exit holes where the insects bore through the bark, s-shaped “galleries” under the bark, and increased woodpecker activity. Birds can remove the outer layer of bark in pursuit of the beetles, exposing the light-colored bark underneath in a process called “blonding.”
Residents can slow the spread of the insect by keeping firewood containing ash logs within five miles of its source, or season the firewood at its source for 12 months, or only deliver ash wood after Sept. 1 and burn it before June 1.
Suspected sightings of the beetle itself can be reported through the University of New Hampshire Extension website, https://nhbugs.org/invasive-insect-reporting-form.