As we enjoy skipping through the summery outdoors or just lounging in the warm weather, we are also reminded to beware. Since we are constantly growing the list of things to be cautious about, we should feel okay about adding caterpillars to the roster.

For the summer season, they humbly join snakes, water activities, and a host of fellow bugs in ratcheting up the horror factor for us. Why caterpillars, you say? It’s not just any caterpillar, but the gypsy moth caterpillar.

Sure, they look fascinating and cuddly on the outside – harmless even – but what people are learning the hard way is that not all images are what they seem. The gypsy moth caterpillar is rubbing people the wrong way with its rash-inducing hairs, and it’s nothing pretty.

The tiny hairs on the caterpillar contain histamine, which causes an itchy rash to develop on the skin. Small bumps can form on the skin and in some cases, will become swollen and red. For some, the rash also becomes unbearably painful and makes it difficult to sleep.

Spread through direct contact with the caterpillars or by contact with their hairs, the rash can appear immediately or hours after being exposed. You may not notice that a caterpillar has crawled on you or that you’ve brushed against some hairs that have blown through the wind or landed on some grass.

Anywhere their little bodies have been could expose you to a potential rash. Rashes are typically found on the limbs, around the neck, on the abdomen, or on the back. If you think you’ve come into contact with the hairs, – called setae – wash your skin and treat the rash with over the counter lotions or ointments.

This species of caterpillar is particularly harmful to trees, and they are known feed off trees and cause serious damage. You may not be able to avoid or address them in nature, but pest control experts suggest using tree bands or pheromone traps near the trees in your yard to keep them at bay.

Infestations can happen anywhere in North America, but Massachusetts has been hit hard. The caterpillars are highly active between May and July, so watch out for the larva, hairy young teens, or fully grown adult versions. They can all cause rashes!

You’ve rooted for caterpillars thanks to that children’s book where one goes on an eating spree (you know the one). You have a weird affinity for caterpillars because of the smart, hookah-smoking one that helped Alice out in Wonderland. But the gypsy moth caterpillar should be avoided at all costs.

Check out this video hear more about the severity of the rash and what you can do to protect yourself. It’s easy to mistake this rash for poison ivy, so if your reaction seems more serious, it’s important to follow up with a doctor. And be sure to scan your kids for red bumps, welts, or the bugs themselves!

Have you ever gotten a rash from this caterpillar? Do you have gypsy moths where you live? How many have you seen at once?