The female moth can lay 1,000 eggs or more, singly or in small groups of up to 30 on grasses, weeds and crop debris. Females seek low-lying and weedy areas to lay eggs. EggĮggs produced by spring migrant moths are often laid before crops are planted. Moths become difficult to identify when they lose their wing scales and markings with age or when otherwise damaged. These markings on the wings are most visible on newly emerged or recently arrived specimens with intact wing scales. The hindwings do not have obvious markings and are pale gray with darker gray near the veins and edges.

Identifying features include a small black dagger or dart-shaped mark that extends outward from a faint kidney - reniform - spot near the light to dark boundary of the forewing. The forewing is dark brown to black with a lighter distal - away from the body when spread for flight - edge. The adult black cutworm is a moderate-sized moth with a wingspan of about 1.5 inches (Figure 1). Depending on when the moths arrive in Minnesota and temperatures, black cutworms will go through one or more generations until late-summer conditions trigger a southward migration. The black cutworm goes through a complete metamorphosis with egg, larval, pupal and adult stages. In addition to corn, the larvae feed on a wide range of broadleaf and grass crops, weeds and other plants. Black cutworm adults feed on plant nectar. The larva -caterpillar - is the life stage that damages crops. In these areas, annual infestations are produced by moths migrating from southern overwintering areas each spring. Although a native of North America, it can’t survive winters in Minnesota or other latitudes with freezing winter temperatures. The black cutworm – Agrostis ipsilon Hüfnagel (Lepidoptera: Noctuidae) – is widely distributed in the temperate regions of the world. Find information about black cutworm in Minnesota corn, including their characteristics, habitat, at-risk fields, signs of damage and strategies for managing infestations.

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