The Gypsy Moth, Lymantria dispar, is an insect with four life stages.

* Gypsy Moth eggs are laid in the fall, with 50-1000 eggs per egg mass or cluster. The female covers the clusters with hairs from her abdomen. Egg masses can be found on tree trunks and limbs, on the sides and under the eaves of buildings, on lawn furniture, campers, bricks, rocks, birdfeeders, firewood, and virtually anything found outdoors. Gypsy Moth caterpillars hatch in April and May, depending on weather conditions.

* Caterpillars are the larval stage of the Gypsy Moth. As they grow, the caterpillars shed their skins several times to accommodate each succeeding body size. Each growth stage where the caterpillar sheds its skin is called an instar. Males usually go through five instars and females go through six, because of their larger body size. Older Gypsy Moth caterpillars have two rows of colored spots on their backs, five pairs of blue spots and six pairs of red. They have long hairs along their sides. Depending on weather conditions and food, the larval stage can last from May through July.

* When the caterpillars have reached their last instar, they stop eating and pupate. They no longer eat or move around. Instead, they spin a cocoon of silk and remain in the pupa state for about 10 days. It is during this stage that metamorphosis takes place.

* Adult moths emerge from the pupae from mid July to mid August. The male moth is tan to dark brown and is often seen flying erratically during daylight hours. He is actually trying to find the female moths, to mate. Females are white in color and have a larger body to accommodate the eggs. Since female Gypsy Moths do not fly, they emit a strong chemical, or pheromone, to attract the male. Adult moths do not eat. They usually live less than a week, during which time they mate, lay eggs, and die.

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