PEST PROFILES: MOTH AND BUTTERFLY CATERPILLARS
Redhumped caterpillar

Description:
Mature redhumped caterpillars are about 1 to 1-1/2 inches long. The head and a conspicuous hump on the body are red. The body is yellow or reddish with white, yellow and black stripes and rows of black tubercles. Adult females measure about 1-1/4 to 1-1/2 inches across, with wings extended; male is slightly smaller. Body is brown and forewings of both sexes are mainly brown with a gray outer edge and a spot near the middle.

Damage:
A defoliator that prefers apple, but also feeds on plum, cherry, pear, apricot, as well as some other fruit, nut and shade trees.

Life cycle:
Overwinters as a larva inside a cocoon. Pupates in early summer and adults emerge end of June. In July, females begin ovipositing on undersides of leaves near branch ends. Young larvae work down the branch, at first eating only the undersides of leaves but later consuming entire leaves. When disturbed, they discharge a defensive odorous fluid. When mature, in August and September, they descend to the ground and hide under leaves or debris, where they form cocoons.