Spongy moth (Lymantria dispar) [formerly known as the “gypsy moth”] was brought to North America in 1869 by an artist named Mr. L. Trouvelot in a misguided attempt to breed a hardy silkworm. Some escaped and the first recorded defoliation by spongy moth was in 1889 of the street trees in Trouvelot’s own neighborhood of Medford, Massachusetts.
Lacking many natural enemies, spongy moth has escalated into one of the most important insect pests of forest and shade trees in the eastern United States. They have moved steadily westward ever since, reaching Wisconsin in the late 1980s.
Spongy moth is native to Europe, Asia, and North Africa. It has succeeded so well in North America for several reasons: