Browntail Moth Spotlight

Browntail Moth Spotlight

February 27, 2026

Browntail Moth (Euproctis chrysorrhoea L.) populations decreased in some areas in 2025, but are still elevated in others. Check trees this winter to see whether your community may be impacted by browntail moth this spring. If you find winter webs, take action to make a difference!

Browntail Moth (BTM) is an invasive insect of forest and human health concern that feeds on oak, apple, cherry, crabapple, elm, birch, popular, shadbush, and rugosa rose bushes in Maine. BTM caterpillars have irritating hairs that break off their bodies and settle in the environment, causing an itchy rash for humans that come in contact with the hairs.

In the winter, look for palm-sized BTM winter webs at the tips of trees to see if you may be dealing with BTM caterpillars in the spring and summer. Actions to take in the winter and spring:

• Scout for and remove winter webs with hand snips or an extendable pole pruner in areas you can safely reach. Destroy webs in a contained fire or soak the webs in a bucket of soapy water for a few days before disposing.
• Find professional help if you can't reach and remove winter webs. Licensed arborists, pesticide applicators, and FAA-certified drone operators may be able to help you remove webs or treat your infested trees to reduce BTM populations.
• Insecticide treatments in mid-April to mid-May may also be effective at reducing populations.

In mid-April, BTM caterpillars will emerge from their winter webs and begin feeding on the buds and leaves of their host trees until late June. Actions to take in late spring and summer:

• Learn how to identify the browntail caterpillar and avoid areas where these caterpillars have been.
• Change clothes and shower after working in infested areas to wash away irritating hairs and prevent the rash.
• Keep outdoor lights off in July to dissuade BTM adult moths from flying near your dooryard and laying eggs in nearby trees.

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