Watch out for stinging caterpillars in San Antonio

Must be the season of the hairy caterpillar

Top left is Hickory tussock caterpillar, top right is Spiny oak slug caterpillar, bottom left is Puss caterpillar and bottom right is Saddleback caterpillar (Jerry A Payne, Wizzie Brown, John Ghent, KSAT)

SAN ANTONIO – Stinging caterpillar season is starting back up in Texas.

You might have seen photos on social media recently of people getting stung by caterpillars and that’s because touching certain caterpillar species can cause contact rashes and painful reactions.

Specifically, the buck moth caterpillar, spiny oak slug caterpillar, hickory tussock moth caterpillar, saddleback caterpillar and Io moth caterpillar can cause a stinging sensation when touched.

These caterpillars are typically prevalent in San Antonio from March through December.

“A good rule of thumb is if a caterpillar looks ‘fuzzy’ — don’t touch it,” said AgriLife Extension specialist Molly Keck.

People will react differently to caterpillar toxins with some developing a more severe reaction than others. Different areas of the body may also have more or less severe reactions depending on the thickness of the skin in the area where you’re stung.

Generally, the pain and rash will go away in a few hours, however, it could take as long as a few days.

Other symptoms after a sting could include nausea, vomiting, headaches, respiratory stress or shock, according to a previous news release from Texas A&M Agrilife Extension.

Asps, also known as puss moth caterpillars, are another species to watch out for. They are furry-looking and have different color variations.

Touching puss moth caterpillars can cause a burning sensation and a rash that could be very itchy and may even require a trip to the emergency room, AgriLife Extension experts say.

Spiny oak slug caterpillar (USDA Agricultural Research Service,

Are the caterpillars a problem in your area?

AgriLife Extension specialist Mike Merchant said puss moth caterpillars can be controlled when they become abundant by spraying with a residual pesticide such as permethrin, cyfluthrin or similar sprays labeled for control of caterpillars on ornamental plants.

“The best solution to dealing with stinging caterpillars may just be educating adults and children on what these caterpillars are, what they look like, and the importance of not touching them with bare hands,” Merchant said.

The experts at AgriLife Extension say you should instead, enjoy the inchworms and fuzzy caterpillars from afar.

These caterpillars will eventually turn into moths and butterflies which help pollinate Texas flowers, fruits and trees.


About the Author:

Mary Claire Patton has been a journalist with KSAT 12 since 2015. She has reported on several high-profile stories during her career at KSAT and specializes in trending news and things to do around Texas and San Antonio.