Egg - White at first, the round eggs have a diameter of 0.5 to 0.7 mm and may become slightly tinted before hatching.
Larva - Black cutworms are greasy-looking, gray to black caterpillars up to 46 mm long. As long as 38 mm when fully grown, spotted cutworms have a pale brown or gray body with black wedge-shaped spots on each segment of the posterior half of the body. The spots increase in size toward the tip of the abdomen. About 50 mm long when mature, variegated cutworms are pale brown with a distinct yellow dot on each segment down the center of the back.
Pupa - Cutworm pupae are bout 20 mm in length and dark brown or mahogany in color.
Host Plants - As general feeders, most cutworms attack a wide range of plants. Some common vegetable hosts include asparagus, bean, cabbage and other crucifers, carrot, celery, corn, lettuce, pea, pepper, potato, rhubarb, and tomato.
Damage - Young cutworms climb plants and feed on spears and ferns of asparagus. The mature cutworm, however, are sluggish, nocturnal, and soil burrowing. They typically sever plant stems during the night and hide in soil near the base of plants during the day.
Life History - Cutworms overwinter as larvae or pupae, depending on the species. In early spring, overwintering larvae of some species become active, feed, and complete their development. In other cases, moths emerge from overwintering pupae and lay eggs on host plants or other vegetation. Therefore, depending on the species, damaging cutworms found in spring may be overwintered larvae or new generation cutworms. Cutworms develop through five to eight larval instars (again depending upon the species).
Pupation occurs in the soil and lasts about 2 weeks for nonoverwintering pupae. Moths emerge and deposit 55 to several hundred eggs on host plants. The number of annual generations depends on latitude. Generally, there are two generations per year in Canada, four generations per year in North Carolina, and five to six generations per year in Florida. The spotted cutworm, however, produces only two generations per year throughout the U.S.
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