Fall armyworms pass the cooler winter months as small, partially grown larvae in the dirt, soil, or under debris in grassy areas such as your yard. They continue to grow and are active even during the cooler winter months, apart from very cold, freezing weather. Once the armyworm is fully grown, the feeding slows down for four days. Then, they will pupate over a 15-20 day period. Adult armyworms will then emerge in May or June. Females will feed on honeydew, nectar, or decaying fruit before they proceed to lay eggs in mass amounts. Eggs are laid during the night hours in clusters of anywhere from 25 to 134 on grass or small grain leaves and vegetation. Just one female armyworm may live as an adult for 17 days and can produce up to 2,000 eggs. Then, the cycle begins all over again.