northeast-flora-and-fauna

Earlier this spring some wooded areas were inundated with the tent-like webs of the Eastern Tent Moth  caterpillars These caterpillars are native to North America, and prefer to feed on apple, crabapple, and cherry trees, though they're not extremely picky eaters. When I was a kid, we mistakenly thought these were Spongy Moth caterpillars, an invasive pest you probably knew by a different name . As an invasive species, the Spongy Moth caterpillars are probably more destructive of the 2 since they have fewer natural predators or parasites. Although the Spongy Moth does make silk, it never makes the tent-like webs found on trees. It sounds to me like tent moth caterpillars are less likely than Spongy Moth caterpillars to damage trees, at least partly because they eat leaves in the spring when trees are better able to regrow their leaves, and partly because they do have plenty of natural predators/parasites in our ecosystem so their populations don't generally get as large. When...

Here's a silk nest of the Eastern Tent Caterpillar . What it is not is a group of Gypsy Moth caterpillars [1]. Both of these species grow up to be moths, and both have the potential to defoliate our trees by eating leaves, but that's about where the similarities end: They're not closely related. Eastern Tent Caterpillars are a native species that our local ecosystems have been dealing with since pre-colonial days. Gypsy Moths are an invasive species brought here in a misguided attempt to create a silk industry here. Eastern Tent Caterpillars can defoliate trees, though this typically occurs early in the growing season and our trees typically refoliate in a couple weeks. Gypsy Moth caterpillars are more likely to defoliate trees, and the trees are less likely to regrow leaves that season. Eastern Tent Caterpillars create the silk "tents" (hence the name) to provide themselves some (imperfect) protection from predators and the elements. They are fairly social as la...