Gypsy Moth

Here to stay, but don't spray!

The caterpillars of this moth are leaf-eating machines! They can completely strip every leaf off an oak tree and many other tree species.

Frankie Barker

Meet the adult moths

Male gypsy moths are brown with a darker-brown wing pattern. Females are slightly larger and almost white.

Check out the male's cool antennae!

Gypsy moths have what are called "feathery" antennae. Can you guess why?

Gypsy moth female

Female gypsy moths do not fly. They only crawl and spend a lot of their time laying eggs. Here, a female moth has just laid eggs and covered them in protective tan hairs.

Gypsy moth egg masses

Gypsy moth egg masses can contain up to 1,000 eggs and are covered with tan hairs.

Gypsy moth larvae

After eggs hatch in the spring, the caterpillars (larvae) feed on tree leaves. The caterpillars will grow and shed their skin several times before transforming into adults.

Gypsy moth larvae

Gypsy moth caterpillars (larvae) have a mottled yellow or gray pattern with tufts of bristlelike hairs. You can recognize them by spotting the five pairs of blue dots followed by six pairs of red dots that run along their backs.

Gypsy Moth Pupae

When they are ready, the caterpillars (larvae) will go through a stage called "pupation," a transformation period where they change into adult moths. The cocoons you see in the photo are called "pupae."

Gypsy Moth Field Guide

Gypsy Moth

Click to download a PDF version of this field guide6.5 MB

The Moth's Favorite Trees I

Gypsy moths feed on several types of birch trees. The outer bark of this paper birch is smooth, thin, and white. The paper birch grows along stream banks, lakeshores, and on the moist slopes of hills.

These moths feed on over 100 species of trees, including oaks. Oak trees can grow to heights of 100 feet or more. Acorns are a good sign that you have spotted an oak tree!

Sweetgum is also a favorite of gypsy moths. These trees have star-shaped leaves with 3-7 lobes and spiky fruit.

The Moth's Favorite Trees II

Aspen is another favorite of the gypsy moth. The big-tooth aspen has shiny leaves and a long petiole , which makes the leaves ripple easily in the wind.

Gypsy moths can feed on over 100 species of plants, including oak trees like the one in this picture.

Watch and Learn to Identify the Gypsy Moth!

Trees in Trouble I

The larvae or caterpillars chew holes in leaves. They are very efficient eaters and can strip trees of all their leaves in short periods of time.

An egg mass can contain up to 1,000 eggs and is covered with tan-colored hairs. The masses can be found on trees, logs, and buildings.

Gypsy moth larvae feeding on leaves⁠—caught in the act!

Trees in Trouble II

Entire trees can lose their leaves from hungry caterpillars!

This is a forested area in summer that is recovering from a gypsy moth infestation.

Gypsy moths have stripped this tree of all its leaves!

Slow the Spread

Gypsy moths have an unlikely natural predator—a fungus ! The fungus produces spores (seen in the picture to the right) that stick to the caterpillar 's fuzzy hairs. After the caterpillars die, the hairs drift away in the wind and carry the spores to a new location, where they'll infect other caterpillars. Pretty neat!

Deer mice are an important native and natural enemy of the gypsy moth.

Traps that smell like female moths attract the males. If there are male moths in the traps, scientists know that nearby trees are at risk of a gypsy moth invasion!

Gypsy moth larvae nest: Milan Zubrik, Bugwood.org.; Adult : Leslie J. Mehrhoff, University of Connecticut, Bugwood.org.; Male and female: USDA APHIS PPQ, Bugwood.org.; Antennae: WJ Postma, Flickr.com.; Egg masses: Karla Salp, Washington State Department of Agriculture, Bugwood.org.; Larva : Ferenc Lakatos, University of Sopron, Bugwood.org.; Pupa : Pennsylvania Department of Conservation and Natural Resources - Forestry, Bugwood.org.; Birch: David Lee, Bugwood.org.; Acorns: Allen Bridgman, South Carolina Department of Natural Resources, Bugwood.org.; Sweetgum: RH, Flickr.com.; Aspen: Vern Wilkins, Indiana University, Bugwood.org.; Oak tree: John Picken, Flickr.com.; Leaf holes: John Ghent, Bugwood.org.; Egg masses on tree trunk: Milan Zubrik, Forest Research Institute - Slovakia, Bugwood.org.; Moths feeding: Haruta Ovidiu, University of Oradea, Bugwood.org.; Defoliated tree: Ferenc Lakatos, Bugwood.org.; Defoliated tree, recovering trees: Wisconsin State Department of Agriculture, Flickr.com.; Deer mouse: Dave Cappaert, Bugwood.org.; Gypsy moth trap: Daniel Herms, The Ohio State University, Bugwood.org.