From Bugwoodwiki

Gypsy moth egg masses were brought to the Boston area in 1869 from France for experimental crossbreeding with the silkworm. Unfortunately some of the larvae escaped and became established on the local vegetation. The insect has now spread throughout New England, the Mid-Atlantic States, southeastern Quebec, and central Michigan. Scattered infestations have been reported along the East Coast to Florida to as far as California. Hosts include most hardwoods and any conifer that might be mixed in with the more favored hosts of oak, gray birch, and poplar. Yellow-poplar and ash are usually avoided, but in outbreak situations the larvae will eat just about anything.

In late summer, eggs are deposited in masses (fig 13) containing 75 to 800 eggs that are covered with buff to light-brown hairs from the female’s abdomen (fig 14). These hairs insulate the eggs from low winter temperatures. Most egg masses are deposited on the trunks and limbs of trees, but they can also be found under stones, inside hollow trees and stumps, on leaves, and on various manmade objects. Eggs hatch in late April or early May, usually about the time the oak leaves are expanding.

Newly hatched larvae move from the egg masses toward the top of the tree. When disturbed, larvae will spin down on silken threads; this behavioral trait, along with a small body size and long body hairs, makes this stage very susceptible to airborne dispersal by the wind. This type of dispersal can spread an infestation up to 1.6 (1 mile) in flat terrian or more than 7 km (4.4 mile) in hilly topography.

A full-grown larva is 40 to 60 mm (1.5 to 2.4 in) long. The head has patches of yellow markings; the body is a dusty or sooty black with tufts of hair on each body segment. On the back is a double row of five pairs of dark blue spots, followed by a double row of six pairs of brick-red spots (fig. 15). Young larvae chew small holes in leaves. Older larvae feed on leaf edges, consuming entire leaves except for the larger veins and the middle rib. Feeding by the large larvae occurs mostly at night. During the day, the larvae congregate in sheltered locations. If trees are completely defoliated before the larval stage is finished, larvae leave the bare trees to search for another food source. This short distance movement can become a nuisance in wooded residential areas. The homeowner becomes acutely aware of the wandering larvae, which fall into swimming pools and climb all over lawn furniture, patios, and shrubbery.

Larval feeding is completed by mid-June or early July and is followed by pupation, which lasts about 2 weeks. The pupa is dark reddish brown with a sprinkling of reddish hairs. Adults emerge and mate from mid-July through August, Egg laying occurs at this time.

The male moth has a wingspan of about 37 mm (1.4 in) and is dark brown with black bands across the forewings (fig. 16). The female is white with variable black bands across the forewings (fig. 16) and her abdomen is covered with buff or light-brown hairs. She is larger, with a wingspan of about 50 mm (2 in.), but rarely flies.

Gallery

gypsy moth
	; Photo by USDA Forest Service Archive, USDA Forest Service, Bugwood.org;
Taxonomy
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Hexapoda (including Insecta)
Order:	Lepidoptera
Family:	Lymantriidae
Genus:	Lymantria
Species:	dispar
Scientific Name
	Lymantria dispar ; (Linnaeus)