Gypsy Moth Suppression Program

Gladwin County

Life Cycle & Stages
Text Box: The gypsy moth has four stages in its development: egg, caterpillar, pupa, and moth. It has one generation each year. Buff-colored egg masses that are covered with hairs from the females belly are laid on just about any object outside from tree trunks to rocks to deer blinds. They begin to lay their egg masses around the middle of July and usually lasts about 3-5 weeks. The eggs will overwinter as they are and begin to hatch the following Spring in April and May. The newly hatched caterpillars are about 1/4-inch long and reach a length of 2 inches by the time they mature. The older caterpillars are very distinctive looking with their dark body, pairs of blue spots followed by pairs of red spots along their back. They have long, dark hairs projecting from their sides. Text Box: Gypsy Moth Life Cycle Text Box: The caterpillars begin to feed soon after hatching and feed through late June or early July. Then they will seek out a sheltered place to pupate. Pupae are usually found under pieces of bark, in crevices, under branches, or in any other protected place; however when populations are high, the caterpillars will pupate just about anywhere. The adult moths will begin to emerge in July. The males are smaller than the heavier-bodied females. They have brownish colored wings with many darker brown markings on them. Their wingspan is about 1 1/2 inches and they are strong fliers. The females have white wings with smaller, darker brown markings and a wingspan of about 2 inches. The females do not fly, but stay pretty close to where their pupation sites is, where they release a pheromone (scent) to attract the males. After mating, each female lays a single egg mass that may contain up to 1,500 eggs before she dies.