Gypsy moth caterpillars hatch

Those of you who are regular readers of this blog may remember a post from last fall. It was about a gypsy moth caught in the act of laying eggs. I decided not to destroy that egg mass.

Early this week, the eggs hatched. In the photo you can see how small and seemingly helpless they are at this stage of their life. They are less than 1/16th  of an inch long. A single rain drop could probably crush a baby caterpillar if it landed right on it. Or, at the very least, wash it from the tree branch.

Well over a hundred caterpillars hatched from this single gypsy moth egg mass.

Well over 100 caterpillars hatched from this single gypsy moth egg mass.

So how do these small caterpillars survive our spring rain storms?

Looking at the egg mass, I think I figured it out. The mama gypsy moth lays her eggs on the underside of a branch where the baby caterpillars are well protected from direct rainfall. I’m sure many get washed away but many survive to live another day.

This is also the stage at which they are most vulnerable to insecticides. You can imagine it wouldn’t take much spray to kill these pests now compared to later in the season when they have grown into full-sized caterpillars.

Bob Dluzen
As a result of being a gardener for more than 40 years, 30 of those as a professional, Bob's gardening has become an integral part of his life. "It's the ever-changing seasons and the wide variety of plants and gardens that keeps me intrigued," he says. Bob lives and gardens in rural Monroe County.