Gypsy Moth CaterpillarGypsy Moth in Wisconsin
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Each year, gypsy moth caterpillars defoliate thousands of acres of hardwood forests throughout northeastern United States, including Wisconsin. This site offers tips on how to limit damage to your trees and available assistance programs.

October  

 

Sign up now for spray suppression program

Look for egg masses in crevices and protected hiding spots on rough bark, the undersides of branches, under signs attached to trees, and even on buildings, play equipment, benches, and picnic tables.

You can predict whether gypsy moth caterpillars are likely to defoliate your trees next June. This is best done once leaves have fallen. Directions on how to perform a predictive survey.

If you want to participate in the suppression spray next spring, contact your county suppression coordinator now.

When the temperature is above 40°F, spray egg masses with Golden Pest Spray Oil to kill them and reduce the population of gypsy moth next spring. You can also scrape egg masses into a cup and either microwave them on high for 2 minutes or cover them with soapy water for 2 days. You may then discard eggs in the trash. Don't just scrape eggs onto the ground, they will survive to hatch next spring!

Pulling up the bark to look underneath.

 

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