Problems and timing may not apply outside of this area. 1998 Gypsy moths are serious insect pests of trees and can cause extensive damage to trees and forests. In Illinois, the gypsy moth exists, but for the past several years numbers have been low. In 1997, however, those numbers went up dramatically, and are anticipated to be high in 1998. Today and next week I'll discuss this pest and the situation here in northeastern Illinois.
Gypsy moths are an introduced species to the United States.
Larva do not make silken webs or tents in trees. Silken tents visible in trees in spring are from Eastern tent caterpillar, and those appearing later in summer are the work of the fall webworm. Gypsy moth caterpillars are brown, hairy, and have a double row of several red and blue dots on their backs. They usually feed in large groups, primarily at night, in May and early June. Among their favorite host trees are oak, apple, alder, aspen, basswood, hawthorn, and birch.