We add our voice to that of the Maine Forest Service, which this month is encouraging residents to take advantage of the dormant season of the brown-tail moth to reduce its effects.

According to the Forest Service, brown-tail moth populations in Maine have been in an outbreak phase since 2015 and the pest cannot be eradicated. Most areas of Maine, especially settled areas with significant host tree populations, such as oak, apple, crabapple, pear, birch, cherry or other hardwoods, are at risk of infestation by the caterpillars. While long-lasting tree defoliation and branch dieback are major concerns, the moths’ microscopic, toxic hairs can cause trouble breathing and skin irritation similar to poison ivy from a few hours up to several weeks.

Waldo County is among the areas most affected in the state, according to information on the Forest Service’s website. A May 2020 map indicating the risk of exposure to the insects showed 13 of the 26 towns in the county at high risk, with an additional three at moderate risk. A 2021 survey of brown-tail moth damage, primarily to trees, found 29,750 acres in the county had been damaged, the third-highest among Maine counties.

The Forest Service says winter is the best time to clip and destroy the moths’ winter webs within reach or hire licensed arborists or pesticide applicators to reduce out-of-reach populations. It urges residents to follow what it calls “the four Rs,” to help control the pest. They include:

Recognize: Learn how to identify trees that contain brown-tail moth winter webs where you live, work and play. Winter webs can look like single leaves hanging onto twigs or fist-sized clumps of leaves tied together tightly with silk. Knowing where the nests are in your yard or town can help inform homeowners’ management decisions.

Remove: With the property owner’s permission, use hand snips or extendable pole pruners to remove webs that can be reached from the ground and are not near hazards such as power lines. Protect your eyes and skin from hairs that might be present from past caterpillar activity. After removal, destroy webs by burning or soaking in soapy water for several days, then dispose of the nests in the trash, the Forest Service advises.

Recruit: Hire a professional to treat webs out of reach or near hazards. Line up help during winter. Licensed professional arborists can remove brown-tail moth webs in larger trees and shrubs in the winter. In trees where the caterpillars’ hairs cause a nuisance and where it is not practical to remove the webs, licensed pesticide applicators may be able to use insecticides during the growing season to manage the pests. Lists of these professionals can be found on the Forest Service website.

Reach out: Finally, if you find brown-tail moths in your neighborhood, let your neighbors and town officials know. The more neighbors, businesses and others get together to respond to the problem, the better the results.

Encounters with hairs from brown-tail moth caterpillars can cause mild to severe rashes and respiratory problems. Some people say they experience itching with fewer than 10 webs per tree or shrub, according to the Forest Service; others say they have no symptoms from heavier infestations around their yards.

This pest destroys trees and shrubs and harms people’s health. Though it cannot be eradicated, it can be controlled. Now is the time to seek out and destroy its webs to reduce the damage it can do in the coming season.

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