Landowner Management

You are the first line of defense for protecting your property from damage by gypsy moth. Take time to inspect your trees, shrubs, structures, lawn objects, and recreational vehicles periodically for the various life forms of gypsy moth.

Egg Masses

Do not remove egg masses in the fall, they must be left where the female moth laid the mass so they are counted by a fall survey team. You may destroy all egg masses in the month of April before they hatch. Scrape them into a bucket of soapy water and let them sit for a day.

Reducing Caterpillar Numbers
Mechanical Controls (Cloth and Barrier Bands) (PDF) can be used on trees in your yard to help reduce the number of caterpillars feeding on foliage of the trees. Conventional chemical insecticides can effectively control gypsy moth in some situations. However, precautionary measures must be followed to avoid toxicity to humans, animals and other non-target organisms. Always follow all label instructions when using these or any other pest control product.


We need everyone’s help in detecting gypsy moth populations and keeping this insect from spreading to new neighborhoods. Failure to inspect household articles for gypsy moth life stages prior to movement from a regulated area is a violation of U.S. Department of Agriculture quarantine regulations and may result in significant civil penalties.

Using Btk

To be most effective in minimizing defoliation, Btk - Bacillus thuringiensis var. kurstaki (commonly found in soil and on plants) - is applied by aerial spraying when the caterpillars are less than 1 inch long. When caterpillars eat Btk the protein crystals dissolve in their digestive system and become toxic. Within 1 to 2 days they die.

As caterpillars get larger, the efficiency of Btk diminishes. Btk has a reported residual activity (i.e., how long it remains potent) of about 1 week and is broken down by sunlight. Btk is only known to be toxic to feeding caterpillars of moths and butterflies and is quite safe to humans, birds, fish, pets, beneficial insects and other non-target organisms.