Is that tree trunk moving? And what’s a bagworm anyway?

If things that crawl make you squirm, spring in Charlotte may not be the time of year for you.

Some trees near the corner of South College and East Stonewall streets in uptown Charlotte have been invaded with Eastern Tent Caterpillars.

The annual return of the caterpillars, sometimes referred to as bagworms, can make the trunks of trees appear to be undulating when masses of the creatures climb to the tree tops in regions of the United States east of the Mississippi River.

The caterpillar is no friend of trees or shrubbery. While winding their way into the foliage the hungry little critters strip away the new spring leaves. If an area or an entire plant shows signs of no foliage and browning, that area is dead. It will not recover.

Eventually the caterpillars become moths and seek mates.

What’s a bagwom?

Bagworms are often confused or the name is used interchangeably with the Eastern Tent Caterpillar, according to the N.C. Cooperative Extension.

“Bagworms are small ... The worms live inside bags they make from the tree’s foliage. The bags can be easily missed because the worms camouflage the bags with parts of the tree,” the extension’s website states.

An Eastern Tent Caterpillar, on the other hand, “forms webs in the crotches of a tree in late-spring into summer,” according to the extension office. The caterpillars are distinctive, with a gold or white stripe down their black body.