Northern Prairie Wildlife Research Center
Wingspan 4.0 cm. Forewing is dark gray with black basal and anal margin dashes, postmedian band with a sharply dentate margin; hindwing is white. This noctuid is common and widely distributed in western North America. Moths fly in midsummer. Caterpillars feed on the foliage of alder (Alnus) and willow (Salix).
Similar species: Acronicta radcliffei postmedian band of the forewing with a smooth margin, hindwing brown, occurs in the Pacific West.