cutworm, name for the larvae of many moths of the family Noctuidae (owlet moths). These larvae, or caterpillars, feed at night on the stems and roots of young plants, often cutting them off near the surface of the ground. They hide in soil by day. They attack a wide variety of field crops in low-lying areas; an average cutworm feeding on corn consumes 65 sq in. (410 sq cm) of foliage during its development. Most species pupate (see insect) underground. Many species overwinter in the pupal stage, the adults emerging in the spring and laying eggs from which the larvae hatch in summer. The number of generations occurring during the summer varies with the species and the climate. Cutworms are classified in the phylum Arthropoda, class Insecta, order Lepidoptera, family Noctuidae.