A Technical Report from The Bartlett Tree Research Laboratories
The bagworm is an unusual caterpillar and serious defoliating pest of many ornamental trees and shrubs throughout the eastern half of the United States. The bagworm receives its name from the bag-like structure constructed from leaf fragments that are bound together with silk produced by the larva. Most of this insect's life is spent within the bag, which serves as a protective structure. Bags blend in with the host and infestations often go unnoticed until significant defoliation has occurred.