Q:  I was sprayed and I was not notified!

A:  Notifications occur in two (2) forms – a municipality is required to give general notice to the public by placing a legal notice and a large format display ad the local newspaper. Additionally, property owners in areas to be treated are notified by first class mail.

When loud, low-flying spray aircraft are turning around and maneuvering, adjacent properties outside treatment areas are frequently overflown – but never sprayed. Those property owners were not directly notified, and are often startled and assume that they are being sprayed. Some may even smell engine exhaust and become nauseated; however the insecticide used on the treatment program (B.t.k.) is odorless, and harmless to humans and pets.

Q:  My property was not sprayed. What can a homeowner do to be included in the Department’s Cooperative Gypsy Moth Suppression Program?

A:  Since there are certain legal and fiscal requirements for participation in the aerial spray program, the Department can only work with local municipal governments or agencies. However, when a municipality requests an egg mass survey, we send Department inspectors to the municipality to pick up a map and request locations of complaints of gypsy moth damage. The homeowner can play an active role in this process by requesting that your municipal officials ask the Department for a gypsy moth egg mass survey and filing a written complaint about the location of these gypsy moth infestations with your municipality by early September. Follow up this letter with another request in late December to determine if your area was indeed included in a spray block and if your municipality is participating in the cooperative program.

If your area contains high populations of the gypsy moth and your municipality either decided not to participate in the voluntary program, or your area did not qualify for the program (because of insufficient acreage), you may contact private spray applicators to have your area sprayed during early spring. The best time to spray for gypsy moth caterpillar control is in early May (from May 5-31), depending on the insecticide to be used and the larval development. In general, the caterpillars should be about ½ inch long and the foliage should be at least 1/3 grown when sprays are to be applied. If you decide to treat your own property for gypsy moth control be sure to use only those insecticides labeled for the control of gypsy moths and follow the directions on the label carefully.

There is additional information on the New Jersey Department of Agriculture’s webpage at www.nj.gov/agriculture/divisions/pi/prog/gypsymoth.html

Q:  I pay taxes, why is my property not being sprayed?

A:  The Department of Agriculture coordinates the gypsy moth spray program; it is not a state-funded program. Municipalities are responsible to pay the vendor for the costs of the treatment; municipal participation in the aerial spray program is completely voluntary. If the residential or recreational wooded area has as average of more than 500 egg masses per acre, and is at least 50 acres in size, it may qualify for participation in the cooperative gypsy moth suppression program. The Department of Agriculture recommends areas to be treated, but the local municipality makes the final determination.

The treatment areas are normally 400 to 600 foot wide swaths along roads or developments. Properties beyond that in deep woods areas are not treated to conserve natural predators and parasites of gypsy moth.

Q:  How does the control program work?

A:  Municipalities with heavy infestations of gypsy moths, as determined by a summer aerial defoliation survey, are contacted in writing by the Department in early fall, and asked if they wish to have a gypsy moth egg mass count. This is done to determine if the infestation will continue and delineate what areas may qualify for the spray program. If the residential or recreational forest has as average of more than 500 egg masses per acre, and is at least 50 acres in size it may qualify for participation in the cooperative gypsy moth suppression program. Municipal participation in the aerial spray program is completely voluntary.

In addition to delineating treatment areas, the Department bids a consolidated master contract to allow municipalities to get the best price for aerial treatments. Participating municipalities pay the vendor for the full costs of the treatments. The Department chooses the insecticide to be sprayed, and supervises the actual spray operation. The Department also applies for U.S.D.A. Forest Service cost sharing funds which, if funds are available, can provide up to a 50 percent reimbursement of the treatment cost to the participating municipalities.

Q:  Why is the Department involved in gypsy moth control programs?

A:  The suppression program works to protect against serious tree loss. The gypsy moth, in its caterpillar stage, is the most destructive hardwood defoliator ever to occur in New Jersey. Gypsy moth caterpillars feed on hundreds of types of trees and shrubs - even grass when the population is extreme - but it is their feeding effects on oak trees, and pine, spruce and hemlocks that is most significant. Oak trees can only sustain 2-3 years of repeated defoliation before high numbers of trees are killed; upwards of 15 to 65 percent may be killed; conifers may be killed after one season of heavy defoliation. Each year, since 1970, gypsy moth caterpillars have caused varying degrees of defoliation (leaf loss) between 1,910 - 800,000 acres of forest land.

Q:  What is the name of the insecticide used in the treatment program, and how does it work?

A:  The biological insecticide used in the gypsy moth spray program is named Bacillus thuringiensis, B.t.k. It is a highly selective bacterium that when eaten by the gypsy moth caterpillar, enters the stomach, and rapidly multiplies causing a paralysis of the stomach wall which stops the caterpillar from feeding. Death usually occurs within 5 to 7 days. The insecticide is most effective against the smaller caterpillars so proper timing of the spray is extremely important to get the best results.

B.t.k. is odorless, and harmless to humans and pets. If B.t.k. droplets should spot your car or truck finish, they can easily be removed through hand washing the vehicle with soap and water.

Q:  Why aren’t chemical insecticides being used in the Department’s gypsy moth spray program?

A:  Chemical insecticides may adversely affect beneficial insects, such as honeybees and/or aquatic insects, however B.t.k. does not. This biological insecticide only affects leaf feeding caterpillars and is considered safe for people and pets. For this reason, the Department strictly uses this material in its Gypsy Moth Spray Program. This materials use has greater acceptance by the public because of this low toxicity toward non-target organisms especially in highly residential areas. It does not provide the same degree of caterpillar reduction as the chemical insecticides, but in more than 70 percent of the cases, satisfactory foliage protection is obtained. This protection is usually sufficient to prevent tree mortality.

Q:  Is there any alternative to spraying?

A:  The New Jersey Department of Agriculture is recognized as a leader in promoting the use of biological control measures against a variety of agricultural and forest pests. For many years the Department reared and released millions of parasites and predators of the gypsy moth in order to establish a means of natural control. In some regions of the state, these parasites and predators have worked very well in stabilizing gypsy moth populations for many years. By selectively spraying only residential and recreational area, (treating only a small portion of the entire infestation), we are allowing these natural predators and parasites every opportunity to control the growth of gypsy moth populations. However, where epidemic numbers of the gypsy moth exist, the natural enemies cannot prevent heavy defoliation, in these areas, aerial sprays are recommended on a selective basis. Various mechanical control measures, such as egg mass removal or adult moth trapping may have some value at low population levels (less than 10 egg masses per acre) but have little effect when populations are high (520 egg masses per acre or more).

Q:  What do gypsy moth caterpillars like to feed on? How can I be sure I am not mistaking gypsy moth for some other plant pest?

A:  The gypsy moth feeds on a wide variety of trees, which include oak, maple, birch, beech willow, and hickory. The larger caterpillars also have been known to feed on pine, spruce, hemlock and many common ornamentals. Trees that are rarely attacked by the gypsy moth larvae include tulip poplar, ash, dogwood, rhododendron and cedar. The gypsy moth caterpillar, when fully grown, is about 2 inches long, and has pairs of blue and red spots on its back.

Eastern tent caterpillar is most often mistaken for the gypsy moth. The Eastern tent caterpillar is a native insect, which feeds on black cherry, crabapple, hawthorn trees and apple trees exclusively. The Eastern tent caterpillar forms the highly visible white "tents" in the branches of trees. Eastern tent caterpillars may be a nuisance, but they do not pose the same threat to our forests or shade trees as the gypsy moth. The Eastern tent caterpillar is also about 2 inches long, black with a white stripe along the middle of the back and a row of pale blue oval spots on each side. It is sparsely covered with fine light brown hairs.

Q:  What causes increases and decreases in gypsy moth populations?

A:  The gypsy moth first began defoliating New Jersey forests in 1966. Three major population cycles have occurred, one in 1972 when 256,000 acres were defoliated, another in 1981 when 798,000 acres were defoliated, and another in 1990 when 431,000 acres were defoliated.

A cycle is completed when after years of steady build-up, the larval populations peak and dramatically crash the following season. This is caused by fungal and viral disease outbreaks, along with starvation, which have reduced populations from 80 to 90 percent in certain areas. The most effective natural control is a fungal disease. Parasites and predators also help to keep gypsy moth populations at low levels in conjunction with these fungal and viral outbreaks. These periods of stable low gypsy moth populations may last for five years or more.

The recent population build-up has occurred because the fungus disease has not been active for the last 4 spring seasons due to dry weather. The fungus is present in the soil in the woodlands, but needs wet, rainy weather when caterpillars are feeding and crawling around to thrive and infect the gypsy moth population.

For more information contact the New Jersey Department of Agriculture at (609) 292-5440 or the Dept. of Agriculture Gypsy Moth web site at www.nj.gov/agriculture/divisions/pi/prog/gypsymoth.html