Spongy Moth Suppression

Keeping Spongy Moths Under Control

A new common name for Lymantria dispar, spongy moth, replaced the prior name of this insect, gypsy moth, in 2022. 

How to spot spongy moths:

  • Color: Females are generally light tan with brown or dark tan bars on their wings. Female Spongy Moths do not fly.
  • Caterpillars: Adult larvae develop five pairs of raised blue spots and six pairs of raised reddish spots on their bodies.
  • Egg masses: Found on the bark of trees, egg masses are most visible in the late fall after leaves have fallen. Egg masses are generally 1 1/2 inches long and shaped like teardrops. They appear to be wrapped in a tan-colored felt cloth. Viable egg masses are spongy, without noticeable exit holes. They also can be found under decks and on woodpiles, outdoor furniture and playground equipment. They should be removed or destroyed by April to prevent them from becoming caterpillars.

Further Identification Tips

It is NOT a Spongy Moth if it is:

  • Building a cottony nest or web in trees
  • A white moth that flies
  • Larger than a 50 cent piece and colorful
  • A caterpillar with long stripes on its back or sides
  • Flying in the springtime

To get more information about spongy moths and their management call 800-642-MOTH (6684) or visit the University of Wisconsin-Extension Spongy Moth website or the Wisconsin Spongy Moth portal website.