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What Katy Newcomers Need to Know During Asp Season


October 27, 2022

By Natalie Cook Clark

Late October and early November is Asp mating season, which brings these critters out and often in contact with Katy residents and pets. Here’s what you need to know about this cute (but not friendly) caterpillar-like creature that can give a big sting.

It's Katy Asp Season

Katy continues to see newcomers flood into the area, but really all Katy residents need this reminder. It’s important to know the area and its critters. Late October and early November marks asp mating season, a time that often brings these furry critters out. These cute looking bugs often emerge in residential yards putting them in the direct path of Katy residents and their families.

What are Tree Asps?

Tree asps, like most stinging caterpillars, belong to the family of flannel moths - in this case - the Southern Flannel Moth. They're tricky to spot - lots are only about the size of a quarter. The ones found around here are teardrop shaped, and their hair resembles cotton or fur that's gray to reddish brown. More mature asps have wings.

A Painful Encounter

While in moth form, these critters are harmless, however, their earlier furry, caterpillar forms can actually be dangerous. The caterpillar's furry appearance can lure curious children and pets to touch or play with them.

A few years ago, the youngest daughter of the Headley family was enjoying a fun evening in Kelliwood Estates when a seemingly harmless science lesson turned terrifying. Katy Dad, Clint Headley found the caterpillar on a bush and picked it up to introduce it to his three-year-old daughter. The caterpillar did not sting him. Not knowing he'd picked up a tree asp, Clint turned the encounter into a science lesson about caterpillars.

When their science discussion was over, they returned the caterpillar to a plant in the yard and bid it farewell. That's when Clint's daughter, Makensi leaned in to kiss it goodbye. The preschooler erupted into screams and tears as the asp (it was no innocent caterpillar) injected many stingers, that looked like tiny fibers into her upper lip.

A Cinco Ranch resident caught this asp on film earlier this week.

Getting Stung

The Headleys used tape to remove all of the stingers, and then gave their daughter Benadryl and pain medication.

"Makensi slept a lot that evening, and her lip was still swollen and painful the next morning," says her mother Andrea.

The next day, Makensi still had swollen lips, pain, and didn't want to eat so they took their daughter to the pediatrician.

"We continued to treat with Tylenol and Benadryl as instructed by her doctor, and on the fourth day after the attack she woke up saying it didn't hurt anymore," says Andrea.

When stung by an asp, it's wise to call a doctor and/or seek immediate medical attention, as the Headleys did with Makensi. The burning will continue until all the hairs have been removed, making the asp's sting very painful.

Some websites recommend oral antihistamines to reduce swelling and itching. But for further medical treatment and severe reactions, like uncontrolled rashes and difficulty breathing, always contact a doctor immediately.

Recognizing the Asps

"I didn't know about these asps," said Andrea. "I had seen one on my dog's leash about an hour earlier. Luckily I used another part of the leash to knock it off."

In the immature stages (pictured above), a tree asp is covered in fine hairs and spines packed with venom that produce an extremely painful rash or sting. In particular, the caterpillars local to Katy can be found:

  • In the shade of trees and under leaves

  • On playground equipment, such as slides

  • On and under patio furniture

How to Avoid the Asps

With spring excitement and summer nearing, many families may spend more time outside. Everyone should be cautious and aware of what could be enjoying the outdoors too.

Avoid going anywhere barefoot, to avoid innocently stepping on an asp. Also, check playground equipment to make sure there are no creepy tree asps hiding somewhere unseen.

Protecting Furry Friends

Our furry friends may also be attracted to the asps. If your dog does get stung, websites say to apply an ice pack to the area and/or a baking soda paste to treat the swelling. Just like with humans, always try to safely remove the stingers. Tape is helpful. Seek the advice of a veterinarian with any concerns.

Cautioning Children

The Headleys certainly don't want a repeat of this experience.

"I am telling my kids not to kiss any more animals, especially ones they haven’t seen,” warns Andrea. “They need to find us before they get close to any critters - especially small ones."


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