In urban areas, gypsy moth caterpillars are nuisances as they feed on shade and ornamental trees and shrubs. The caterpillars and debris from their feeding get into pools, on sides of houses, on patios, etc.
Severe defoliation reduces host plant vigor, which allows for secondary pest infection.
During a long-term outbreak, repeated defoliation can result in host death. Extensive defoliation of forested areas is unsightly and costly. Heavily damaged park and forest lands are not attractive to tourism. Industry that depends on aspen for raw material and firewood also may find supplies reduced. Gypsy moth defoliation can alter wildlife habitats.