Gypsy Moths

So... What are Gypsy Moths?

Adult male and female gypsy moths have several distinct differences. Males are dark brown and very good at flying while females are white, grow larger and heavier, and cannot fly.

The larvae of both sexes are about 2 1/2" long with blue and red dots on the backs of the larvae. The larvae have sections of hair throughout the length of their bodies.

Although the eggs of the gypsy moth are a yellowish color at first, they may turn white due to winter sunlight.

Reproduction Patterns of Gypsy Moths

The eggs of the gypsy moth generally spend the winter attached to trees and hatch in May when many trees begin to produce blossoms.

Larvae suspend themselves from trees by silken threads and are picked up by the wind and carried to another tree or shrub a mile or more away.

A larva will go through several stages until it pupates and matures into an adult gypsy moth around the beginning of June. The male is able to fly about, but the female ascends the trees and deposits her eggs that will spend the winter there.

After the eggs have been deposited, the female and male gypsy moths will both die.

Gypsy Moth's Habitat

This forest scourge is found throughout the eastern regions of the United States and Canada. It has reached areas of the central U.S. as well.

Small infestations sometimes occur in western states, but these appear to be due largely to the accidental transportation of the moth to these areas via cars and trucks and the materials they carry.

Symptoms of Gypsy Moth Damage

Defoliation of a large area of trees is one of the prime symptoms indicating the presence of a gypsy moth infestation. Gypsy moth larvae can actually be seen crawling up trees, roads, walls, and other outdoor areas especially when there is a particularly large outbreak in the region.

Results of a Gypsy Moth Infestation

Trees that are heavily defoliated by gypsy moth larvae may become weakened and die. Trees that do not die may become stunted in their growth. Trees in a weakened state are more susceptible to disease and other damaging insects which can end up killing the trees.

Gypsy Moth Controls

What?

B.t. and pyrethrins are chemicals that can be used to help control young gypsy larvae. B.t. (Bacillus thuringiensis) is a method of eliminating your garden or field of the gypsy moth larvae without environmental concerns or harm to wildlife and beneficial insects.

Insecticides containing pyrethrins can effectively control the gypsy moth.

How?

B.t. kills gypsy moth larvae, thereby preventing further damage. When the worm ingests the B.t., it works as a gut rot poison that makes the worm stop feeding. The gypsy moth larvae will stop feeding immediately and die within days of malnutrition. B.t. can be found in a spray, granular or dust.

Carefully read and follow all directions on the product's label. This product is very specific and only works on caterpillars and leaf feeding worms. It will not harm beneficial insects, children, pets or wildlife.

Sprays with pyrethrins paralyze the insects and result in their death.

When?

B.t. is generally applied when it is a cooler time of day, preferably later in the afternoon or early in the evening since the product breaks down in sunlight and heat. Carefully read and follow all directions on the product's label.

Safer^® Brand offers a variety of gypsy moth and larva control products to help control and eliminate this garden pest and revive your plants. Please check out our gypsy moth and larva control products for more details about how they work and how, when, where they should be applied.

It is recommended with any pesticide to test plants for sensitivity to the product. Spray a small section of the plant in an inconspicuous area and wait 24 hours before full coverage.

When applying pyrethrins to infected plants, carefully read and follow all directions on the product labeling for application. Do not spray plants in the peak of the day or when temperatures exceed 90°F.

Natural Predators

What?

Parasitic wasps, ground beetles, and tachinid flies are all parasitic insects of the Gypsy Moth. Some of these are also good at killing other insect pests.

Birds, including robins, blue jays, grackles, chickadees, starlings and red-winged blackbirds, will eat the moths, helping to control infestations.

How?

Parasitic insects attack gypsy moth eggs and lay their own eggs in the larvae. Birds eat both the larvae and adults of the gypsy moths.

When?

Parasitic insects attack the eggs after they are laid, and attack the larvae when the larvae are generally young. When migrating birds return to areas with gypsy moth populations in the spring, they can feed on the hatched larvae.

Most local greenhouses and garden centers can help you determine the right planting time for nectar and pollen producing plants to ensure that the pollen and nectar will be available when the wasps arrive.

Environmental Controls

What?

Removing vegetative debris and trash from your yard, especially near your home, keeping trees healthy, and destroying eggs are all ways to help control the gypsy moth and larvae. In addition, be sure you are not transporting the larvae or moths on your vehicle or in your vehicle.

How?

Remove any dead branches or plants and trash from your yard and discard in tightly closed containers and place out when it's trash day. Make sure your trees are in good soil, get plenty of water, and are surrounded by mulch where possible. Eggs can be destroyed by scraping them off the surface when found.

When?

Remove all vegetable debris and trash throughout the year, but especially in mid to late summer before the female moths have laid their eggs. Water and fertilize your trees as needed.

Look for eggs to destroy in the fall and winter after the females have laid their eggs. Before exiting an area with an outbreak of gypsy moth, check your vehicle, luggage and supplies to be sure the moths and larvae are not hitching a ride.