Egg Mass on bark

The Gypsy Moth is an important pest that feeds on oaks and many other forest and shade trees.
The Gypsy moth can be introduced into new areas if egg masses or other life stages are accidentally transported on vehicles, trailers, forewood or other objects.
Egg masses are tan, covered with fine hairs, and range in size from one to three inches long. They are often laid in protected locations.
Inspect outdoor furniture, vehicles, firewood and other articles before moving them to be sure that you are not carrying gypsy moth into a new area.
Each egg mass will produce 500 to 1000 gypsy moth caterpillars. If you find gypsy moth egg masses, scrape them off and let them soak in soapy water for 4 to 5 days.
Egg masses can also be burned or buried.
- When do the larvae emerge from their masses?
In early to mid-May, they then papate into adults in mid-June to early July
- When are the eggs laid?
The female lays the egg masses in July-August
- At What Stage Do They Do The Most Damage?
The larva or caterpillar is the damaging stage as it eats the leaves of trees in the spring. They can consume tremendous amounts of leaf material. For example, Gypsy moth larvae can consume as much as one square foot of leaves per day. As a result, they produce a large amount of fecal (frass) material. When populations reach outbreak proportions, the caterpillars can completely defoliate host trees over a wide geographic area. Consistent or repeated defoliation over several years can have devastating effects, often leading to tree stress and death.