The emerald ash borer: What we know, what’s being done, what we can do, what we can expect

By Cherise Madigan
©2020 Telegraph Publishing LLC

Last October, a Londonderry landowner found a green beetle with a red abdomen lodged in his door. Inspection from a forester and entomologist confirmed that the insect was the invasive emerald ash borer that — though first found in Vermont in 2018 — was not expected in the region for years.

Recently, a new infestation has been reported in West Rutland as local, regional and state officials continue to prepare for the ash borer beetle’s potential impact.

Their message to Vermonters? Don’t panic, but begin preparing.

The ash borer, which feeds on white, green and black ash trees, was first found in the United States in 2002. Since then, the invasive Asian beetle has spread across the country carrying a 99.9 percent mortality rate — particularly for white ash trees, which is the most prevalent type of ash in Vermont. Five to 7 percent of Vermont’s overall trees are ash and often are found on roadsides – a concern among town governments and power companies alike.

Ash trees are dangerous when they fall, often breaking into pieces, posing a hazard for both individuals and property.

The state’s largest infestation remains at the intersection of Caledonia, Orange and Washington counties, according to state entomologist Judy Rosovsky, who participated in a community forum in Londonderry last January. The infestation in Rutland County found this fall, however, leaves only three Vermont counties in which the ash borer has not been found: Essex, Lamoille and Windsor. In Windsor, infestations have been found within 10 miles of the border in neighboring New Hampshire.

The good news, Rosovsky says, is that the areas where trees are dying in significant numbers are still limited. Locally, Londonderry is the only town with a confirmed infestation though the “infested area” includes Windham, Landgrove and most of Weston, Andover, Peru, Winhall, and Jamaica. Chester, Stratton and others remain in the “high risk” area.

“So far, the Londonderry infestation seems to be light and confined to one small area,” Rosovsky said. “People will have years to get ready for the pest to come and start killing its ash trees. That’s not to say we shouldn’t be concerned, but it’s not going to happen overnight or next year. You have a little bit of time to plan ahead.”

Towns begin preparing for ash borer

Because the ash borer cannot simply be “sprayed and sent away,” she explains, planning has become paramount to address its invasion. Such eradication attempts in other states have proved futile, Rosovsky said, though the Vermont agencies of Natural Resources and Agriculture are currently working with the USDA to introduce biocontrol agents. The agents most often used to counter the ash borer are parasitoids, or insects whose parasitic larvae eventually kill their hosts.

Biocontrol agents won’t do much to prevent a “first wave” of tree deaths though, Rosovsky says, and state agencies are also actively pursuing roadside surveys, volunteer trapping programs and citizen reports.

Regionally, volunteers deployed purple traps this year and may do so again next year, said Windham County Forester Sam Schneski. The Department of Forests, Parks and Recreation has also been helping towns coordinate inventories of ash trees on town land and rights of way.

“The inventory will help towns determine their course of action and finances relating to potential hazard tree mitigation,” Schneski said.

In Londonderry, Tree Warden Kevin Beattie has begun such an inventory after the town approved $3,000 to address the problem last year. Beattie says more money will likely continue to be appropriated by the town in coming years.

“I’ve inventoried a little over half of the roads and I think we’re looking at about 1,500 ash trees within town right-of-ways,” he said. “Some of those the power companies or utility companies will be responsible for, but not the ones that are away from their right of ways.”

Beattie said the inventory hasn’t found further signs of infestation, adding that it may be years before ash trees begin dying off. “We know it’s coming, and we’re getting ready,” he said.

Nearby Weston has also pursued an inventory of its ash trees. When the ash borer begins to have an impact on Weston, the town plans to follow a straightforward strategy laid out when the ash borer was found in Londonderry: Road Foreman Almon Crandall will cut down impacted trees, and a professional will be hired to handle any trees that Crandall cannot.

Other towns in the region, like Chester, are just beginning to coordinate such an inventory — with some interruptions from the Covid-19 pandemic. Initially, Chester Highway Foreman Kirby Putnam had hoped to organize a volunteer effort to log the town’s ash trees, even eyeing local students in search of work-study and field learning opportunities.

While social distancing requirements have delayed those plans, Putnam hopes that an inventory can begin within the next year. “Once we get that established it will make it a lot easier to figure out where we need to go from there,” he said.

What landowners, residents can do

In the meantime, what should residents and landowners do? First, experts advise exercising caution when transporting firewood. Doing so during the ash borer flight season — which ended on Sept. 30 — is illegal due to a federal quarantine, but campers or homeowners should still limit the distance that their firewood travels. Studies have shown that the ash borer’s larvae can live up to two years in cut firewood, which is how the beetle is most often transported.

Additionally, landowners should learn what the ash tree looks like, begin determining how many are on their property and start developing a plan of action. Though it will likely be years before the infestation grows to the point where trees are dying en masse, removing ashes while they are still alive is important for safety reasons .

“Be aware of [the emerald ash borer] and know the symptoms of an infestation,” said Windham County’s Schneski.

“If you have an ash tree around your home, they can be very dangerous once they die,” Putnam said, adding that many tree companies will no longer climb ashes. “Once the ash is infected it kills the tree and it kills the root system but it may not fall over, it may break halfway up.”

Beattie added that Londonderry residents who think they may have an ash borer infestation can call him to verify as much, and that no ash trees should leave the “infested” area surrounding the town. Most importantly, Beattie stressed, residents should not panic since the region still has years to continue addressing the infestation — a notion which Rosovsky echoed.

“Don’t move firewood, and don’t panic,” the entomologist encouraged. “There is still time to get ready for the emerald ash borer.”

Learn more about the emerald ash borer, or report trees that you suspect have been infected, by clicking here.