What happens when gypsy moth becomes established?
Once gypsy moths become permanently established, it may take several more years for moth populations to build before residents see any noticeable defoliation. The first outbreak may last 3 to 15 years depending on weather patterns, local site conditions and the presence of natural enemies. Typically, the first outbreak is by far the most severe because there are abundant host trees and very few natural enemies present. The first outbreak is when most environmental, social, and economic impacts will occur as a result of repeated defoliation and associated tree mortality. Competition for food, increasing disease, and natural enemies eventually cause gypsy moth populations to collapse. After the first outbreak, gypsy moth populations behave more like those of native insects, with cyclic outbreaks every 8 to 12 years.
