Gypsy Moth 2014-1015 Report

Burkman, Peggy

Gypsy moth (Lymantria dispar) is an invasive species from Europe, first introduced near Boston, Massachusetts in the late 1860’s. First detected in Wisconsin during 1971 they have since spread throughout Wisconsin’s 71 counties. Gypsy moths are one of the most damaging species to North American native trees in because they are able to feed on a diverse range of species. Populations exist in four distinct phases. Phase 1 is mild with a very low population level that may persist for years. Phase 2 is the release phase (one to two years) and the population density steadily increases. This steady increase causes an outbreak phase, which happens when noticeable defoliation throughout the forest occurs (rarely last more than one to two years). In the outbreak phase, populations of gypsy moths become too high for forests to sustain them; starvation and disease cause the death of significant numbers. This rapid decline of individuals is the final die-off phase with a steep decline in the local gypsy moth population (Elkinton and Liebhold 1990). Determining the current population phase promotes understanding of potential harm, including degree of problems, to the environment. Monitoring has occurred at plots on Basswood and Stockton Island since 2009 and in 2014 completed in cooperation with Jonathan B. Thayn of Illinois State University and his students (Stockton).