The gypsy moth is probably the most important defoliating insect of hardwoods—especially the oak—in the northeastern United States. This insect is often confused with other forest Insects of similar size, shape, and coloring. Much effort and money have been spent to control or to eliminate this pest from this continent. Yet it continues to spread southward along the Appalachians. The objective of this brochure is to help landowners and other interested individuals identify this forest pest and its life stages.