Gypsy Moth Management Plan Fredericksburg and Spotsylvania National Military Park 1992 Environmental Assessment

Perez, John

The gypsy moth was inadvertently introduced into New England over a century ago. The spread of this alien species has been slowly moving south and west since that time. The gypsy moth has been found in localized infestations throughout the United States with the heaviest populations concentrated in the northeast. The advancing front of the moth is now in north-central Virginia and eastern West Virginia. The progression southward continues at a rate of approximately ten miles per year. Since this pest is often carried by wind or vehicles into non-infested areas, any location with suitable habitat is subject to defoliation. The high degree of vehicular visitation coupled with abundant habitat puts Fredericksburg and Spotsylvania National Military Park at an especially high risk. The National Park Service (NPS) in conjunction with the U.S. Forest Service (USFS) and the Animal and Plant Health Inspection Service (APHIS) began a trapping program the park in 1982. Populations remained relatively low until 1988 when a dramatic increase was noted. Egg mass surveys did not result in any positive finds until 1987 and by 1990 infestations exceeding 20,000/acre were found at Ellwood in Wilderness Battlefield. To attenuate adverse effects and in response to National Park Service policy, the park has undertaken an integrated pest management program for the gypsy moth in cooperation with the U.S. Forest Service. This program emphasizes population monitoring to identify critical action thresholds, for which appropriate management activities can be made most effective. Natural controls are to be maximized with environmentally acceptable insecticides being used only when appropriate. Control efforts proposed for 1991 include two aerial applications of biological controls to 235 acres of the 6,000 acres in the park ownership. At the present time the primary need for the proposed project is to reduce the impact of the gypsy moth in park development zones. Developed zones include Visitor Centers and grounds, picnic areas, interpretive waysides, and areas of concentrated visitor use. Defoliation of the forest canopy would result in increased mortality in these trees, predominantly oaks, already subjected to recreation related stress. Increased mortality and trees with poor vigor resulting from defoliation would increase hazards to public safety.