This moth is about one-half inch in length and has long, narrow wings. The forewings are orange and have four bands of black that contain yellow spots. Larvae have a green-brown stripe on the back and alternating bands of white and olive-green stripes along the sides.
Ailanthus webworm larvae feed on the nonnative tree-of-heaven (Ailanthus altissima) and the leaves of other woody plants and shrubs. This moth species has been able to increase its range in the United States as the tree-of-heaven, a native of China, has spread. It is believed the moth was originally native to southern Florida and other tropical areas of North America. The adult moth is a pollinator and feeds on flower nectar. It is active during the day. Larva pull two or more leaves together on their host plant and surround them with a web, then eat the leaves and any bark available. The entire life cycle can occur in four weeks, and many generations may be produced in a single summer. Larvae are active from about May through October.