Only in rare circumstances do any of these species cause economic damage to field crops. Black cutworm is the most destructive cutworm in the northern states, and may occasionally cause severe damage to field crops. Biology and Life Cycle Black cutworms migrate as adults from southern states in mid- to late May, depending on wind patterns and temperatures during development. Eggs are white and deposited singly or in small clusters on short weeds and soybean stubble. Larvae hatch and begin feeding 3-6 days after oviposition.
Cutworms have a wide host range and most field crops are acceptable hosts.
Two black dots of unequal size on each segment are indicative of black cutworm . Additionally, black cutworms are typically found below ground, while dingy cutworms feed above ground on foliage. Feeding occurs primarily at night, and larvae rest under the soil surface during the day. Several generations are common in Minnesota, but only the first is of economic importance. Damage The most significant damage caused by cutworms is the cutting of seedling stems above or below the soil surface.