Browse by Subject
Contact Information

Northern Research Station
11 Campus Blvd., Suite 200
Newtown Square, PA 19073
(610) 557-4017
(610) 557-4132 TTY/TDD

Forest Disturbance Processes

Asian Gypsy Moth

Asian gypsy moths laying egg masses near lights on a Russian vessel while in port.The main focus of this gypsy moth work is on the type with flight-capable females, generally referred to as the “Asian” gypsy moth because of the origin of the original interceptions. For regulatory purposes, the United States Department of Agriculture refers to any type/subspecies of Lymantria dispar possessing female flight capability as the Asian gypsy moth. 

The gypsy moth (Lymantria dispar L.) is one of the most serious defoliating forest pests, capable of causing widespread outbreaks in temperate northern hemisphere. The gypsy moth range in Eurasia is roughly between 60°N and 30°N, but does extend further south (20° N) in the Far East.  Multiple introductions of gypsy moth strains with flight-capable females have occurred from egg masses on ships and cargo entering ports in western North America from Japan and Far East Russian ports, and from pupae on military equipment or trooper belongings entering the eastern United States from Germany. Most introductions have prompted an eradication program, the largest of which occurred in 1992 and 1994. The biggest concern over these introductions is the presence of flight-capable females in the introduced strains (and possibly in hybrids between them and the existing flightless strain) might increase the potential rate of spread and complicate procedures for detecting and delimiting isolated populations. In addition, there are other concerns because of the wide variation in behavioral, physiological, and genetic characteristics exhibited by the gypsy moth across its geographic range.  For example, some strains from Asia possess traits that make them more threatening to North American forests than the established Western European strain, including a broader host range, shortened egg chill requirements, and female attraction to lights that results in egg deposition on vehicles or cargo. Since the mid 1990s, quarantine-based proactive research has been conducted on Lymantria dispar (gypsy moth) from Eurasia.

Our Proactive Research Done Under Quarantine


Last Modified: 07/13/2017