Texas is home to over 50 species of stinging caterpillars, with encounters peaking from April through June. Among the most common species in the Houston area is the asp caterpillar, also known as the puss caterpillar.
Wizzie Brown, a senior extension program specialist with Texas A&M AgriLife Extension Service, described the asp caterpillar as having a soft, fur-like covering that may tempt people to touch it.
“They are a teardrop shape and look very, very soft, like you should touch them, but you should not,” Brown warned.
These caterpillars predominately inhabit locations west of I-35 and extend eastward across Texas, covering a vast region.
In addition to the asp caterpillar, other stinging species encountered in Texas include buck moth caterpillars, io moth caterpillars, hag moths, and saddleback caterpillars.
Brown noted that these species are not invasive; they typically reside in large trees, living quietly and often going unnoticed.
“A lot of them are going to be in broadleaf trees, and most of the time, if it’s a mature tree, you don’t really know that they’re there,” she said.
Brown explained that stinging caterpillars usually come to the forefront when there are large numbers of them or when a person unwittingly sits beneath a tree and one falls onto them.
The majority of these caterpillars share a common method for delivering their venom.
“Generally, stinging caterpillars have some sort of spine on their body that is attached to a venom gland,” Brown elaborated.
When contact is made with the spine, it may either inject venom or break off, dispersing venom on the skin, which can spark a reaction.
The severity of the sting varies from individual to individual, influenced by factors such as personal health and sensitivity to the particular venom.
“Depending on who you are and how your body reacts to that particular venom, it could manifest as localized pain, swelling, redness, or even more severe reactions if you have an allergic reaction to it,” Brown stated.
She urged individuals to keep an eye on their health and that of their children.
If abnormal swelling, excruciating pain, heart palpitations, or breathing difficulties arise, Brown encourages seeking medical attention promptly.
Homeowners may confront challenges in managing caterpillar infestations, especially when they are snugly nested in large, mature trees.
A specific bacterium called Bacillus thuringiensis kurstaki can be utilized to combat these caterpillars.
“They do have to ingest enough of the product while feeding on the foliage, but it will only kill caterpillars,” Brown explained.
This method provides a solution for controlling caterpillar populations without harming beneficial insects.
Ultimately, Brown reassured that these caterpillars generally do not pose a threat to people.
All stinging caterpillars cease to be venomous once they transform into moths.
“They’re just doing their thing,” she remarked.
Concerns regarding stinging caterpillars primarily arise in areas such as school grounds and playgrounds where children play.
As warmer months approach, awareness of these intriguing yet potentially harmful creatures is vital for safety.
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