Feeding by even large numbers of the adults is unlikely to cause serious damage. Sprays of insecticidal soap or summer spray oil will provide control, if needed. Fall webworm, yellow-necked caterpillars, and other caterpillars being found on trees and shrubs. Although these caterpillars may strip the leaves off fairly large branches, the branches will releaf next year. Damage of this type occurring late in the growing season does not seriously affect plant health.
Various insecticides are effective, if needed.