They pass most of the summer in the soil as a prepupa, with pupation occurring in August. Adult moths emerge from the cell during late summer, mate and lay eggs soon after. Pale western cutworm has one generation per year. Dry weather favors pale western cutworm survival. Excessive precipitation in the spring can drown larvae in low-lying areas or force larvae to the surface of the soil where they are exposed to attack by predators and parasites.
Wet weather produces conditions favorable for the increase of pathogens.
The adult pale western cutworm is a gray to brownish white, heavy-bodied moth. Distinct markings on the wings are absent and the under-surface of the wing is white. Larvae frequently take on a characteristic C-shape when disturbed. The head is yellow-brown with two distinct vertical black dashes that form an inverted V. Adult Monitoring Pheromone traps can be used to monitor adult flights of both cutworm moths. Pheromones are species-specific scents that are produced by females to attract males for the purpose of mating.