Orangestriped Oakworm

These large caterpillars are the larvae of moths. They hatch from clusters of eggs laid on the undersides of oak leaves. Look for orangestriped oakworms in late summer when they make "skeletons" out of the leaves by eating everything but the large veins. In the fall, they crawl to the ground where they overwinter as pupae in the soil.

Control: Healthy trees can tolerate feeding by these caterpillars, but young trees may be weakened if complete defoliation occurs for several years in a row. Bacillus thuringiensis (Bt) is an effective biological control but is difficult to apply to large trees. Other insecticides are available.