The gypsy moth is native to a vast area of Eurasia. The established North American population originated from near Paris, France, and was introduced into Medford, Massachusetts, in 1869 (Ferguson 1978). The North American range expands annually; maps showing generally infested areas are readily available from the U.S. Department of Agriculture (USDA) Forest Service. A map in Appendix G of the 1995 FEIS (USDA Forest Service and Animal and Plant Health Inspection Service 1995, Gypsy moth management in the United States: A cooperative approach, referred to hereafter as the 1995 FEIS) shows the predicted range as of 2010 within the U.S. to extend from northeastern South Carolina across eastern Kentucky and much of Indiana into eastern Illinois and eastern Wisconsin. Spot introductions by human transport can occur almost anywhere in temperate North America. The eventual range of the gypsy moth in North America will almost certainly include most or all climatically suitable forested regions of southern Canada, virtually the entire eastern and central U.S., and probably much of the West.
Gypsy Moth (Lymantria dispar): Impacts and Options for Biodiversity-Oriented Land Managers
Citation
Schweitzer, DF. 2004. Gypsy Moth (Lymantria dispar): Impacts and Options for Biodiversity-Oriented Land Managers. 59 pages. NatureServe: Arlington, Virginia.