These adorable SC fuzzballs pack a nasty sting in the summer. Here’s what to know

If you see this fluffy little fuzzball around South Carolina this summer, give it space.

The southern flannel moth caterpillar may look whimsical, but the venous, stinging hairs covering its body are excruciating to humans.

“Do not touch them. They’ll give you a horrible skin reaction,” said Coastal Carolina University biology professor Chris Hill. “They look all fluffy, but they’re one of the more painful things you can encounter out there.”

According to Hill, a fuzzy coat helps protect caterpillars, discouraging birds from swallowing them. But the southern flannel’s hairs are both venomous and urticating, meaning they “break off spines inside your skin that will really hurt.”

Here’s how to avoid a painful experience with an adorable bug.

What do southern flannel moth caterpillars look like?

Sometimes called puss caterpillars, southern flannel moth caterpillars are characterized by their thick, almost cat-like, coat of tan or gray hairs growing up to a crest down their backs. The tapering hairs growing behind the caterpillars can give them a pointed sort of tail.

The bugs are about an inch to an inch-and-a-half in length in both their larval form and as moths. After emerging from the cocoon, the moths maintain a fluffy coat, but their hairs don’t sting.

When and where are southern flannel moth caterpillars found?

Southern flannel moth caterpillars are most common in the summer and fall. According to the North Carolina State Extension, the moths spawn two generations a year, with peaks of abundance of caterpillars in July and October.

The venomous little fuzzballs don’t attack humans, but poking or brushing against one is a painful experience.

Southern flannel moth caterpillars eat leaves from elm, hackberry, maple, oak and sycamore trees, so areas with those deciduous plants are more likely places for an encounter.

“They actually feed on a big variety of things, oaks, maples, elms, willows, so they could pop up on shrubs or trees almost anywhere,” Hill said. “But they’re not really common.”

What should you do if you touch a southern flannel moth caterpillar?

For those who do accidentally brush up against a southern flannel moth caterpillar, the experience is painful, but doesn’t usually require professional medical attention.

The wound will burn and the area could swell or a rash could develop. Some people also experience abdominal pain, chest pain, difficulty breathing, fever, headache, itching, nausea, numbness, swelling or vision problems.

“It’s like any skin rash, you’ve got to wait it out,” Hill said.

But there are ways to reduce the pain. Merck Manual recommends:

• Putting tape on the site and pulling it off to remove venomous hairs embedded in skin

• Washing the sting with soap and water to remove any stinging hairs or toxin left on skin

• Applying a baking soda slurry, calamine lotion or rubbing alcohol to the sting

• Icing the sting

The Missouri Department of Conservation recommends that those who “are sensitive to insect stings, or if the pain or swelling is intense, worsens, is badly blistered, or doesn’t go away within one to 12 hours, consult a doctor.”

This story was originally published June 24, 2025 at 6:00 AM with the headline "These adorable SC fuzzballs pack a nasty sting in the summer. Here’s what to know."