Eastern Tent Caterpillar

Eastern tent caterpillar (Malacosoma americanum) - North American native
Eastern tent caterpillar (Malacosoma americanum) - North American native

While my naturalist training group was at Andorra Meadow in Roxborough, we took a walk through the meadows into a cool lush upland forest. The forest is located behind the Andorra Meadow area. This combination of meadow and forest side-by-side is an example of how the land of Philadelphia is naturally.

The forest that we walked through is, at most, 150 years old. I don’t think many forests or woodlands in Philadelphia are much more than that. Slightly before that time, the settlers who came to this area went on a tree-cutting frenzy. And most of the trees in the state were cut down.

The forests that you see in the state are most likely to be second-growth forest.

In the forest we saw the web of the Eastern Tent Caterpillar. The female moth lays her black packets of eggs on twigs. After the caterpillars hatch, together the caterpillars weave these communal webs in the fork of tree branches. The caterpillars prefer trees of the Rose family. The web in the photo is a cherry tree, a member of the Rose family.

The Eastern Tent Caterpillar rarely eats all the leaves off the trees, like Gypsy Moths do.

This native moth gets a bad rap from people who unknowingly confuse it with the Gypsy Moth Caterpillar.

The Gypsy Moth is a European insect brought over to New England as an alternative silk producing moth. The Gypsy Moths will eat all the leaves off trees, leaving the tree unable to produce food for itself. And the Gypsy Moth larvae don’t weave the silken web that the Eastern Tent Caterpillars will.

Find more information at on Gypsy Moths at http://www.invasive.org/species/subject.

We're Listening