Black cutworm attacks tomato, corn, bean, and other vegetable plants.    

Symptoms

Black cutworm caterpillars are blackish, thick-bodied, and up to 1 inch long. The adult moth has brown wings with a 1-1/2 inch wingspan.

Black cutworm attacks the transplants and seedlings of tomato, corn, bean, and other vegetables during the night and hides in the soil during the day. Young larvae climb the plant to eat the leaves, whereas older caterpillars eat through the stem of young plants about 1/2 inch above ground and then eat the plant. These older larvae curl their bodies around the stem to feed; thus older plants with thicker stems are less susceptible to attack.  

Life Cycle

Moths migrate north each spring into Illinois from Gulf Coast states. Successive generations occur all summer.  

Management

Use postemergence sprays at the three- to five-leaf stage of sweet corn if 3% of the plants are cut and cutworms are still feeding. Treat asparagus spears when infestations exceed one larva per ten crowns. Ground applications to the base of the plants are most effective.