Pest Type: Insect
Damage to Plant: Leaves are chewed from the treetop down; defoliated trees may die. Deciduous trees are less vulnerable, since they can grow a new set of leaves. The silken bands attaching the bags to trees may girdle and kill young branches.
The dangling silken bags, reaching a length of 2 inches, are more noticeable than the small brown caterpillars—each of which weaves its own bag and drags it along as it feeds. Bagworms are found as far west as Texas.
Life Cycle: In winter, each bag contains as many as 1,000 eggs. In spring, the caterpillars hatch and disperse to feed for a time; then each one tethers its bag to a twig and enters to pupate. In a few days, the moths emerge. The females, wingless and mouthless, remain in their bags; the small, black-winged males fly in to join them. After mating and laying eggs, the females die. There is one generation a year.