Males are much darker than females. Underside is without much contrast between the basal and outer portions of the wings. Summer brood is darker than the spring brood. In the extreme south, females of the spring brood are often yellowish orange.
Females lay eggs at dusk, in short rows on the host plant leaves.
Eggs hatch in about a week, and the young caterpillars are gregarious feeders. Older caterpillars are solitary feeders, and do not eat the main vein of the leaf. Instead, they cut the leaf petiole at the base and it falls to the ground, perhaps a defensive measure eliminating visual or olfactory signs of feeding. Several leaves are used to form the cocoon, which is attached to the host plant by a silk-reinforced petiole. The cocoon hangs from the plant throughout the winter.