skip to main content skip to main navigation
Photo of a gypsy moth caterpillar - Click to enlarge
Proposed Spray Program Announced
For Immediate Release: January 3, 2008
Contact: Lynne Richmond
(609) 633-2954

(TRENTON) – The New Jersey Department of Agriculture is proposing treatment on 112,500 acres of forested land to suppress an expected heavy infestation of gypsy moth caterpillars in May and June of this year.

The Department today announced a proposed spray program in about 100 municipalities and agencies in 17 counties.  Of the 112,500 acres proposed for treatment, more than 87,000 acres would require second treatments.  The overall cost of such a program is estimated at $9 million.

In addition, the State Department of Environmental Protection is proposing treatment on almost 10,000 acres in state parks and forests and the Forest Resource Center in Jackson Township.  About 7,000 of those acres would require second treatments.

“The devastation caused by gypsy moth caterpillars in 2007 was apparent last summer, with vast stands of trees left bare and weakened,” said New Jersey Secretary of Agriculture Charles M. Kuperus.  “The Department of Agriculture is working cooperatively with other state agencies, the federal government, municipalities and other entities to secure the tools and resources needed to effectively control the gypsy moth caterpillar population this year and protect our vitally important shade trees and forests.”

More than 320,000 acres of trees were defoliated by gypsy moth caterpillars in spring 2007, the highest amount since 1990, when more than 431,000 acres of trees experienced leaf loss.

Last year’s defoliation resulted in the death of as many as 14,000 acres of trees due to consecutive defoliation by gypsy moth caterpillars.  Field surveys conducted throughout the fall of 2007 showed that a heavier population of caterpillars will emerge this May and June.  Up to 45,000 acres of trees in New Jersey could be lost this year if the pest is not successfully controlled.

Two to three consecutive years of significant defoliation (defined as 75 percent or more) can kill an otherwise healthy tree. However, any gypsy moth defoliation can make trees more susceptible to other damage that can lead to the death of the tree.   Oak trees are the preferred host for gypsy moths, but the caterpillars can be found feeding on almost any tree in the vicinity.

To qualify for inclusion in the cooperative gypsy moth suppression program a residential or recreational forest must have an average of more than 500 egg masses per acre, and be at least 50 acres in size.  A single egg mass contains up to 1,000 eggs.  Municipal participation in the aerial spray program is voluntary.

Federal cost reimbursement funds are expected to be available to help municipalities if they choose to participate in the program.  The Omnibus Spending Bill signed by President Bush will provide the United States Forest Service’s Forest Health Management Program with $9 million for gypsy moth suppression assistance nationwide.  However, it is uncertain how much of that money will come to New Jersey as other states are facing similar gypsy moth infestations. 

For more information on New Jersey’s gypsy moth suppression program, visit:   Also, for national gypsy moth material, visit