Spring Weather Pattern Associated with Suspected Black Cutworm Moth (Lepidoptera: Noctuidae) Introduction to Iowa 1

Abstract

Meteorological influences on long-distance and local black cutworm (BCW), Agrotis ipsilon Hufnagel, flight were analyzed. Male BCW capture was compared with ratings describing the favorability of meteorological conditions for the suspected transport. The meteorological ratings (SET Rating System) were based on reported influences of environmental factors on BCW flight. Fluctuations of the ratings and of BCW capture coincided in early spring, indicating that the early-spring Iowa and northern Missouri BCW moth populations are composed only of introduced individuals, probably originating in the south-central United States. Moths may be carried several hundred kilometers to Iowa in one to three nights at considerable height by strong southerly winds. Northern Missouri seems more subject to BCW invasion than Iowa because of more numerous southerly wind events.