Gypsy Moth: Most Wanted Pests Threatening Your Lawn [Part 2]

Gypsy moths are one of the most destructive pests to North American forests. Since 1900, it has spread from Massachusetts across New England, the mid-Atlantic states, the Great Lakes and now infesting most of Wisconsin. Some have been found in Minnesota since 1970, but the Minnesota Department of Agriculture (MDA) and Department of Natural Resources (MNDNR) are working hard to slow the spread.

Central Minnesota is now seeing the MNDNR and MDA set traps for gypsy moths to track its spread. Let’s learn more about this pest.

Gypsy Moth

The gypsy moth is one of the most destructive pests of trees and shrubs to ever be introduced into the United States. Gorging themselves on leaves, gypsy moth caterpillars defoliate, weaken, and can kill more than 300 different species of trees.

Since 1970, gypsy moths have defoliated more than 75 million acres of forest in the United States.

Only the caterpillar stage of the gypsy moth feeds. When fully grown, the caterpillar will be approximately 2” long, very hairy and have five pairs of blue dots followed by six pairs of red dots along its back. Adult gypsy moth are gray (male) or white (female) colored hairy moths with a 1½–2” wingspan.

Shortly after the female gypsy moth lays an egg mass, she dies, and the eggs wait out the winter until temperatures rise in the spring and a hatch begins. Upon hatching, small black headed gypsy moth caterpillars climb to the tops of the trees where they may begin to feed.

There is one generation per year.

While healthy trees can usually withstand a tough year of gypsy moth defoliation, trees which are stressed or suffering from drought may die. Keeping your trees healthy is one key to defending against the gypsy moth.

Stop The Spread

Once you’ve identified gypsy moth or their egg masses in the area, there are some steps you can take to fight them. Unfortunately, because it’s a nonnative pest, gypsy moth has few natural predators. and none capable of preventing its eventual establishment in Minnesota.

  • Become familiar with the gypsy moth, its life cycle, and where it might be found.
  • Inspect and remove gypsy moths, caterpillars and egg masses from your vehicles and belongings when traveling in and out of infested areas, as well as if you’re moving from one city to another.
  • Buy firewood produced locally when visiting campgrounds or recreation areas.
  • If you bring firewood with you, be sure to burn it all before leaving. Do not leave firewood for the next visitor.
  • Keep your yard as clean as possible. Remove discarded items, dead branches, stumps, etc., where the adult female moth is likely to lay egg masses. Destroy any egg masses that are found.
  • Sticky tree bands can be placed around tree trunks to help stop the caterpillars movement into and out of the tree canopy.
  • Call Valley Green Companies to safely apply control products to your trees. Our product must be injected into your trees before gypsy moths arrive, and the process should be repeated every other year to prevent the infestation.


Destroying Egg Masses

Gypsy moth egg masses are laid in August and remain in place after the caterpillars hatch in May. They’re teardrop shaped, about 1-2 inches long and contain 600-1,000 eggs. They’re a yellow-brown color, kind of like a manilla folder, and are firm to the touch before hatching but mushy after hatching.

Wear gloves if you’re touching gypsy moth egg masses. The hairs can cause rashes. Put the egg masses in a jar and cover with soapy water for at least 2 days to kill the eggs. If you just knock the mass off the tree onto the ground they’ll still survive.

Remember, if you need help we’re right down the road. Give us a call today!