As Vermont loses its ash trees, towns race to stop the beetle that’s the culprit

Vermont’s environmental experts are imagining a future without ash trees — and that future isn’t far away.

It’s all because the emerald ash borer , an invasive beetle from Asia, is destroying ash trees from the inside out. The beetles’ larvae burrow into and feed on inner layers of bark, damaging the system trees use to transport water and nutrients throughout their branches and leaves.

The beetles, commonly referred to as EAB, have been reported in 72 municipalities across 13 of Vermont’s 14 counties , according to the Vermont Department of Forests, Parks and Recreation.

But the map of detections is on its way “from looking like Swiss cheese, with little pockets of infestations, to being completely covered,” said Elise Schadler, program manager for the department’s Vermont Urban and Community Forestry Program .

“Eventually there’s going to be no ash left, or at least very few. EAB isn’t going away,” Schadler said.

Environmental experts say the primary solution is to control the timeline of that decline by slowing the spread of EAB. Losing every ash tree over the course of a few years could be detrimental to Vermont’s forests and pose a safety risk to town infrastructure as dead trees fall. Losing the same amount of trees over decades, however, would give locals time to stay one step ahead of dramatic changes — and maybe even “give a second generation of ash trees a fighting chance” to grow and preserve the species, said Josh Halman, forest health program manager for the Vermont Department of Forests, Parks and Recreation.

It’s “near-impossible” to tell how many of Vermont’s trees have been infested since the beetle was first reported in the state in 2018, Halman said. All his team knows, he said, is that “EAB is here to stay.”

“In other states, there’s been no success in fully exterminating it or removing it from the landscape,” Halman said. That means all of Vermont’s ash trees will one day be exposed, he said — that’s 150 million trees, accounting for about 5% of the state’s total trees, according to a 2021 report from the Department of Forests, Parks and Recreation.

What’s new this year, Schadler said, is that environmental experts are seeing a “boom in mortality.” Ash trees can take up to three years to show symptoms of infestation, and up to five years to die from those symptoms, she said — which means the trees first infested in Vermont are starting to die en masse.

The loss of ash trees could have serious impacts on Vermont’s ecosystems, said Emily May, pollinator conservation biologist at the Xerces Society, an international nonprofit that advocates for the conservation of invertebrates and their habitats. Nearly 250 species of insects, moths and butterflies across the country rely on ash trees as a source of food, she said, and numerous other species use the trees for habitat.

Vermont’s urban forests — the trees that line streets, sidewalks and parks — will also be affected, Schadler said.

“Street trees truly define a neighborhood, and losing them — especially one as prominent as ash — can entirely change the character of a neighborhood,” she said.

Experts tend to agree that now is the time to act: EAB has already killed tens of millions of ash trees in North America since it was first detected on the continent in 2002, according to the U.S. Department of Agriculture.

But Vermont’s municipalities are often on their own — not only in figuring out what to do to address EAB, but also in funding those initiatives. Schadler said most towns have volunteer tree wardens or tree committees, but no full-time experts. Those towns, she said, also have limited budgets that must cover the town’s entire vegetation management system, not just the protection of ash trees.

Schadler said her forestry program is the only one in the state distributing EAB-specific grants. But the $540,000 in U.S. Forest Service aid that it has given to towns since 2019 is “really just a drop in the bucket of what needs to be done,” she said, and isn’t available to private landowners who want to protect their ash trees from EAB.

‘A matter of balancing strategies’

There are many strategies to address EAB, Schadler said. But each comes with costs — their price tag, yes, but also their effects on the environment and their impacts on community culture.

Burlington City Arborist V.J. Comai said his strategy for the more than 1,000 ash trees along the city’s roads and in its greenbelt and park spaces is “preemptive removal.”

Because the trees could damage cars, power lines, homes and more if they fall after being infested with EAB, Comai said, he doesn’t want to be “playing catch up” and would rather remove the trees before they are ever infested. They’ll likely all be removed within seven years, he said.

Starting in 2019, Comai said his team started planting a variety of tree species around the city’s ash trees  — that way, when ash trees are taken down, a replacement tree is already in place.

“We could spend a lot of money retaining ash trees in a kind of monoculture, only to have some other pest come along that affects them,” he said. “So we’re taking this opportunity to further diversify our canopy. We’re essentially hoping to better protect ourselves from the next species-specific insect or disease that comes along.”

But young, small trees can’t replace everything a mature ash tree provides, said Greg Ranallo, who owns Teachers Tree Service in Shelburne. Mature trees provide shade that lowers ambient temperature, add ambiance that raises property values, and store a large amount of carbon that helps in the fight against climate change.

“We can’t just say goodbye to an entire species of trees all at once,” he said.

Ranallo said pesticide treatments, including the ones his company provides, are a strategy that can deter EAB while still keeping ash trees standing. Many arborists have the technology to inject trees with insecticide , he said, which kills beetles that eat the bark or leaves. The treatment — as long as it is readministered every two to three years — can protect trees for their entire lifetime, he added.

Even so, Comai said, not every community is willing to put insecticides into its environment.

“In Burlington, attitudes towards the use of pesticides and chemicals are a little different than they are in other places. And I think there would have been some public relations issues surrounding that,” he said.

And neither strategy is cheap, Comai said, especially with “municipal budgets being as unpredictable as they are.” He said he can remove the average ash tree for $1,000 and plant and care for a new tree for $200. While pesticide injection prices vary by the size of the tree, the average tree would cost $300 for every treatment, he said — which “adds up fast” when treatments need to be given every few years.

And those prices can be significantly higher, Schadler said, depending on if a town has its own arborist, needs to hire out work, or has negotiated municipal contracts with treatment companies. Some towns, including Essex, have reduced costs by involving locals in EAB protection efforts: their “Adopt-a-Tree” program limits the cost of planting trees by assigning new trees to residents who are responsible for watering and monitoring them.

The truth is every strategy has its environmental drawbacks because they all manipulate ecosystems in some way, said May of the Xerces Society. Using insecticides can be especially dangerous, she said, because they can make their way into ash tree’s pollen and leaves and harm native bees and caterpillars of moths and butterflies.

“So I think it’s a matter of balancing strategies,” May said. “We have to decide what costs we’re willing to deal with.”

Some towns are finding that balance, according to case studies collected by the Vermont Urban and Community Forestry Program. Northfield , for example, in 2020 treated trees deemed of high value to the community with insecticides while removing trees that could become a safety risk.

‘Boots on the ground’

Schadler said that, while towns have control over trees on town land, they aren’t able to control trees on private property, and they don’t have the resources to bring EAB strategies to trees in large forest areas.

That means it’s important for environmental experts to “get boots on the ground and really encourage entire communities to start thinking about how to approach this,” Schadler said.

One community-wide strategy, May said, is to coordinate the creation of “trap tree” areas. Trap trees are made by removing a ring of bark from ash trees, which makes them more attractive to EAB. The beetles will flock there, she said, and leave other trees alone.

Individuals can help limit the spread of EAB, too, she said, by not moving firewood and by reporting any signs of EAB to the Vermont Invasives website . Residents can also help by protecting ash trees from lawn mowers and weed-whackers — damaged ash trees are more attractive to EAB, May said.

Halman said the state is also working to address EAB in heavily-forested areas that towns don’t have the resources to control. Since 2020, Vermont has worked with the USDA’s Animal and Plant Health Inspection Service program to release parasite wasp species that attack EAB. The small, stingless wasps lay their eggs in EAB larvae, which “dramatically slows” how fast the beetle can reproduce and spread, he said. The parasites have already been released at six sites in Vermont, Halman said, with more locations to come.

Ultimately, Schadler said, it’s all about having a plan.

“If towns haven’t thought about this yet, it should be at the top of their list,” she said. “Everyone can do something.”

Read the story on VTDigger here: As Vermont loses its ash trees, towns race to stop the beetle that’s the culprit .