The European gypsy moth is one of the most destructive pests that has ever been introduced to North America. Moth larvae gorge themselves on the foliage of shrubs and trees, leaving the plants bare and susceptible to disease and damage from other pests.
Hairy caterpillars grow up to two inches in length and display five pairs of blue dots followed by six pairs of red dots along their backs. Moths have an inverted V-shape that points to dot markings on their wings. Male moths have feathery antennae and are darker and smaller than females who have tan bodies and creamy white wings.
European gypsy moths are known to settle in up to 300 different tree species but are most commonly found in oaks and aspens.
The range of European gypsy moths is located in the north eastern United States and Canada. They have been found as far west as Wisconsin and as far south as North Carolina.
Only the caterpillar stage feeds, during a larval stage that lasts about seven to eight weeks. Caterpillars feed at the tops of branches; they begin by chewing small holes in the leaves then eat from the outside inward until the tree is stripped of its foliage.
Gypsy moths have a number of natural predators, the most effective being small mammals. Other predators include birds and parasitoids.
Females possess wings but are unable to fly. Males fly in a rapid zigzag pattern in search of females but are capable of direct flight.
Gypsy moths have four stages of life: egg, larva or caterpillar, pupa and adult moth. Females lay a mass of 500 to 1,000 tan, fuzzy eggs in a sheltered area. The eggs remain here over the winter and hatch when the hardwood trees bloom in the spring. Once hatched, larvae feed for seven to eight weeks, pupate in a protected area for two weeks and emerge in moth form, when they will mate and start the cycle over.
Gypsy moths were accidentally introduced to the United States in Medford, Mass., in 1869, by a professor conducting silk research. They have been established in parts of eastern North America for more than a century