Pests and Diseases: Tent Caterpillars

Today’s topic is about tent caterpillars. I remember that they used to set up shop in my Grandma’s crabapple tree. When they were finished, the poor crabapple was almost strip naked of its leaves. My grandma would go out to the tree with a stick and whirl it around in the tent to get rid of the nest. Heaven help any caterpillar that she could get a hold of. It was smushed by her arthritic hands and feet; that caterpillar paid dearly for eating her crabapple’s leaves.

Had Grandma known, she could have went out to her crabapple in the fall and looked for egg masses that look like these:

tent caterpillar

Photo courtesy of Henderson State University

The adult moths lay their eggs in the fall and these masses can be clipped from the tree and disposed of. Or they can be physically removed if the masses are in areas that aren’t suitable for pruning. Once the days warm in the spring, the tiny black caterpillars emerge from the egg mass and relocate to a nearby tree crotch. Here they work on forming their tent which they return to at night. In the mornings, the caterpillars head out to the newly emerging leaves and feast for the day. Once they’ve gorged themselves, they head back to the tent to go nite-nite. This cycle continues for four to six weeks until the caterpillars are ready to strike out on their own. At this point, they travel to other trees to build the cocoon from which the adults will emerge. The adults make their grand entrance into the world in two to four weeks. The adults find their soulmate and after a brief romance, the eggs are deposited for next year. And the cycle continues…

WHAT TYPES OF TREES ARE USUALLY AFFECTED?

Tent caterpillars generally prefer cherries (wild and cultivated), crabapples, apples, peach and plums. But they can also make themselves at home in maples, oaks, poplars and ash. The good thing about tent caterpillars is that they are easy to spot.

tent caterpillar

Photo courtesy of Purdue University

CONTROL METHODS

Since the best defense is a good offense, look for the egg masses in fall if your trees are susceptible to them. If your trees are attacked one year, the chances of your tree falling victim to them in subsequent years is high. Break the cycle by removing the egg masses before the caterpillars have a chance to wreak havoc.

If you don’t catch them before they emerge from their egg masses, consider taking Grandma’s approach. You can physically go after them with your stick and try to remove them by hand. Consider that the caterpillars return to their tent at night so late evening or early morning will be the best time to attack them.

I wished that chickens enjoyed them but from everything I’ve read, they don’t. Do you know of any animals that enjoy tent caterpillars as snacks? If so, please let the other Mid-Atlantic Gardening readers know. Leave me a comment below or e-mail me at stacey@midatlanticgardening.com. Happy gardening!

April 17, 2012Permalink 2 Comments