Browntail moths, Euproctis chrysorrhoea, were introduced into North America from Europe in 1897. Despite their initial rapid spread through the Northeastern U.S. and Canada, today they are only found in small numbers in some New England states.
The Browntail caterpillar is not a picky eater, chewing on leaves from a variety of trees and shrubs. In large numbers, the caterpillars can quickly defoliate host plants in the landscape. From spring into summer, the caterpillars feed and molt, until they reach maturity in mid summer. They pupate on trees and emerge as adults in two weeks. The adult moths mate and lay eggs, which hatch by early fall. Browntail caterpillars overwinter in groups, sheltering in silken tents in the trees.
Browntail caterpillars have tiny hairs known to cause a severe rash, and should not be handled without protective gloves.