According to the Maine Forest Service on Maine.gov, the browntail moth overwinters as caterpillars in colonies that are enclosed within webbed nests of white silk tightly woven around a leaf in trees or shrubs. These browntail moth nests are in a crabapple tree in Brewer. Credit: Linda Coan O'Kresik / BDN

It was just one web spotted high up in a tree off I-95, but it’s enough to confirm that the invasive browntail moth has worked its way north into Aroostook County for the first time. The web was discovered last week in Smyrna by a team from the Maine Department of Agriculture, Conservation and Forestry conducting its annual winter survey.

Detection of the browntail moth web in Smyrna represents the challenges faced by the state in keeping up with the pest as it spreads beyond known browntail moth infestation areas in central and coastal Maine, according to Thomas Schmeelk, Maine Forest Service entomologist.

Browntail moth activity is also widespread in lower numbers around Old Town north to Corinth and is frequently encountered east of the Penobscot River from Route 9 to Amherst.

“It’s not really surprising that a web was found that far north in Smyrna,” Schmeelk said. “They are really good at hitchhiking.”

Schmeelk suspects the winter web found in Smyrna came from browntail moths that travelled up the internstate on a car or truck heading north. He said nests or groups of nests outside the area of infestation are known as satellite populations.

This time of year it’s easy to spot the webs high up in the trees due to the lack of leaves. Schmeelk said if webs are evident, landowners should clip any branches they can reach that hold the webs and destroy them. The easiest ways to destroy a browntail moth web is either by dropping it onto a bucket of soapy water or by burning it.

If the webs are too high to get to, landowners can contact professional arborists to get rid of them before the caterpillars emerge this spring. It’s also a good idea to mark those trees in case the arborists can’t get to them until the spring when the new leaves are out, obscuring any webs.

Browntail moths represent a danger to trees and to the public health in Maine. The caterpillars can defoliate a tree within days of emerging from their cocoons. Those caterpillars also have tiny hairs that can cause mild to severe skin reactions and respiratory problems in humans.

“We ask the public to keep an eye out for errant webs in your travels,” Schmeelk said. “Areas to be on the lookout for satellite populations can be described as a line just north of Houlton to Millinocket to Dover Foxcroft to Bethel south to southern and western York County.”

Julia Bayly

Julia Bayly

Julia Bayly is a reporter at the Bangor Daily News with a regular bi-weekly column. Julia has been a freelance travel writer/photographer since 2000.