Larvae cut a small hole at the side of the ear, through which they emerge. All of the damage caused by corn earworms is not direct. The indirect damage occurs when other insects and disease organisms use the earworm holes as entrance sites. The resulting damage often exceeds that caused by the earworm. They vary in color, being usually light tan-brown, marked with dark gray, irregular lines and a dark area near the tip of the wing.
Hind wings are light tan with a dark band near the margin.
Moths are often found in the daytime resting in the whorl of young corn or at the base of the leaves of older corn. Each female may lay from 1,000 to 3,000 eggs. Larvae vary in color from a light green or pink to nearly black, though most individuals are brownish green. Usually alternating light and dark stripes run the length of the body. To control this pest, plant corn early and apply mineral oil on corn silks five days after silk emergence or apply an insecticide.