Cutworms attack many vegetable crops, grasses, and field crops such as cotton, corn, and peanuts.
The hairless, caterpillar larvae of various night-flying moths, in various colors from black, gray to brown, about 1 and 1/2 inches at maturity, curl up tightly in a spiral shape when disturbed. Black cutworm larvae are dark gray to black, with a pale yellow line down the center of the back and three yellow lines along each side although these yellow lines are not distinct in some. Granulate cutworm larvae are dusty brown with rough granulated skin. Variegated cutworm larvae have a distinct, pale yellow dot on the mid-dorsal line of at least the first four abdominal segments.
Cutworms attack all common turfgrasses, and seedlings or recently transplanted garden vegetables or flowers, severing stems. This early season pest is usually of greatest concern during early development of field crops, typically within 10 to 14 days of crop emergence. Young larvae (up to 1 /2 inch long) feed above ground on various weeds and crops, particularly corn. When larger, they frequently feed at or just below the ground surface, and are more commonly found below ground, when the soil surface is dry and crusted, cutting plants off near ground level. In lawns, they wreck havoc during spring and summer, causing small patches of sod to turn brown and die. Grass blades around the margins of the affected areas show jagged holes along their edges, making the entire lawn look ragged. They feed only at night, spending days hidden in debris or in the thatch near the surface of the soil. At least 8 species are known to damage turf in Oklahoma.