Seasonal development
and life cycle—Foliage-feeding caterpillars
Moths and butterflies have complete metamorphosis and develop through four life stages. Adults have prominent, delicate wings covered with tiny scales that rub off and appear powdery when touched. After mating, the female moth or butterfly lays her eggs singly or in a mass on or near the host plant or nearby soil. Eggs usually hatch in several days. The emerging larvae move singly or in groups to feeding sites on the plant.
Most caterpillars eat voraciously and grow rapidly. Some feed almost continuously. Others, such as cutworm larvae, hide in the soil during the day, emerging to feed at night. Caterpillars shed their old skins about five times before entering a nonactive pupal stage. Some species pupate in silken cocoons, and most species pupate in a characteristic location, such as on the host plant or in litter beneath the plant.
The adult moth or butterfly emerges from the pupal case after several days to several months, depending on the species and season. Some common caterpillars have only one generation per year outdoors; other species have several generations each year and can cause damage throughout the growing season. | 
Stages of development for typical moth or butterfly
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