Individuals who use agricultural chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. A&T State University nor discrimination against similar products or services not mentioned. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by NC State University or N.C. Recommendations for the use of agricultural chemicals are included in this publication as a convenience to the reader. The beet armyworm has several generations per year. The moths are nocturnal and mating and egg laying occur at night. The pupal stage lasts about a week although overwintering pupae develop much longer. Moths that develop from cannibalistic caterpillars lay more eggs than moths that developed from caterpillars that feed only on plant material! Mature beet armyworms tunnel into the soil about an inch or three and form a cell in which they pupate. Beet armyworms are cannibalistic especially when feeding on plants starved for nitrogen. The fifth stage feeds for two to six days. The third and fourth stages last one to three days. When the tiny worms hatch, they feed in groups especially in the growing tips where they usually web several leaves together. Females may cover the eggs with a mat of scales that helps protect them from parasites and insecticides. Eggs are laid in masses of 15 to 150 mostly on the undersides of leaves and mostly within four inches above the soil. Flight activity is greatest in July and August. Females begin laying two days after mating, and they prefer young rather than old plants. Each moth can lay up to 600 eggs during their week-long life although some may live up to 30 days. A new generation of moths molts from pupae. The pupa is smooth and light brown at first, but it soon darkens. Beet armyworms always have a black spot on the side above the second pair of legs (counting from the head). Older caterpillars are green to almost black with stripes along each side. First and second stage caterpillars are pale green with dark heads. The hind wings are whitish with dark edges. The wingspan is an inch or slightly more. The adult beet armyworm, Spodoptera exigua, is a grayish brown moth with a pale circular spot near the middle of the forewing.

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