Corey K. Gerber, Extension Entomology Specialist Adult bagworms are actually moths. Males and females of the same species have a distinctly different appearance. Males are blackish in color, hairy, and have four wings.
Females are yellowish- white in color and have no wings.
These bags may reach two inches in length. Bagworms only have one generation per year. In early June, young bagworms hatch from overwintered eggs laid within the female's bag. As soon as the bagworms emerge from this bag, they will begin to construct one of their own. During this time, the bagworms feed on tree and shrub foliage.