Gypsy moths are considered as one of the most damaging pests of forest trees. Only larval stages of gypsy moths cause serious damage by feeding on the leaves of forest trees. In case of severe infestation, gypsy moth larvae can completely defoliate host trees.
Females of the gypsy moth lays eggs in clusters on the tree trunks. Gypsy moths overwinter as eggs that hatch early in the spring into first stage larvae that do not feed. The first stage larvae then molt into second stage larvae that starts feeding on the leaves until they reach to their maturity in late June. Matured larvae then pupate on the tree trunks, walls or other structures in July. Adult moths emerge from pupae from late July through August. Gypsy moths generally complete one generation in a year.