Browntail Moth
Euproctis chrysorrhoea (L.)

Maine is experiencing extreme dryness, which is compounding the risks of skin and respiratory irritation from encounters with browntail moth caterpillar hairs. Browntail moth hairs can irritate even when the caterpillars are no longer active, especially in dry conditions and in conditions that stir up the dust. All counties in southern, Midcoast, Downeast, and south-central Maine are at some risk of browntail moth exposure.

  • Quick Access to Browntail Moth Information
  • Contact 211 Maine for more information on browntail moths:
  • Close up of overwintering webs of browntail moth in northern red oak (Maine Forest Service Photo, April 2018)
  • Close up of overwintering webs of browntail moth in ornamental crabapple (Maine Forest Service Photo, February 2017)
  • Caterpillar of browntail moth (Maine Forest Service Photo, May 26, 2016)
  • Communal cocoon of browntail moth in an ornamental crabapple (Maine Forest Service Photo, June 20, 2016)
  • Communal cocoons of browntail moth (Maine Forest Service Photos)
  • Adult browntail moths (Maine Forest Service Photos, July 15, 2016)
  • Browntail moth eggs and adult (Bath Forestry Division Photo, July 17, 2017)
  • Late-summer browntail moth larvae and webs (Maine Forest Service Photos)
  • Browntail moth overwintering webs (Maine Forest Service Photos)

General Information

The browntail moth is an insect of forest and human health concern which was accidently introduced into Somerville, Massachusetts from Europe in 1897.  By 1913, the insect had spread to all of the New England states and New Brunswick and Nova Scotia. Since that time, populations of this pest slowly decreased due to natural controls until the 1960's, when browntail moth was limited to Cape Cod and a few islands off the Maine coast in Casco Bay. Browntail moth populations are again building in Maine and are found in patches from the western Maine border to east of the Penobscot River. A map of the known distribution of the pest in Maine is linked below.

Browntail Moth Risk Map (PDF 2.44 MB)

The larval stage (caterpillar) of this insect feeds on the foliage of hardwood trees and shrubs including: oak, shadbush, apple, cherry, beach plum, and rugosa rose. Larval feeding causes reduction of growth and occasional mortality of valued trees and shrubs. While feeding damage may cause some concern, the primary impact on humans by browntail moth results from contact with poisonous hairs produced by the caterpillars. Microscopic, toxic hairs break off the caterpillars and can be airborne or settled on surfaces in browntail moth infested areas. Sensitive individuals who encounter the hairs may develop a skin rash similar to poison ivy and/or trouble breathing. Symptoms can last anywhere from a few hours to several weeks and can be severe in some individuals.

Maine 211 - Get Connected. Get Answers.For More Information:
Dial: 211 or 866-811-5695
Text Zip Code to 898-211

Background Information

Survey & Management Resources

Frequently Asked Questions

Video on Removing Browntail Caterpillar Nests

Removing Browntail Caterpillar Nests from Jeff Fischer on Vimeo.
Maine Browntail Moth Roadside Population Assessment: Winter 2018 (PDF 2.1 MB)

Use extreme caution if burning webs. Never burn unless the branches have been clipped off. This type of burning requires a burn permit. For more information, please visit and check the daily forest fire danger report.