Poisonous Caterpillars: What to Know

Just when you thought it was safe to grab your pruning shears and head into your backyard, you start hearing stories straight out of a horror movie: venomous caterpillars that not only damage your landscaping but could send you to the hospital if you accidentally touch them.

Four so-called stinging caterpillars call Southwest Florida home: the puss caterpillar, saddleback caterpillar, io moth caterpillar, and the hag caterpillar. According to research by the University of Florida, these nuisance pests don’t sting their victims but poke them with spines that are connected to poison glands. Most people just experience itching or burning when they touch one of these caterpillars, but others may have more severe reactions and need to visit an emergency room.

Because each of these caterpillars feasts on a wide variety of flowers, bushes, and trees, it is a good idea to know what they look like and where they are found. Sometimes, they are hard to avoid. The University of Florida recommends that anyone spending time in their garden, trimming trees or pruning bushes, should wear gloves as a precaution against accidentally touching one of these toxic caterpillars.

Pay attention to railings, benches, and the lawn beneath some of these plants as well because these caterpillars might have dropped down there. How can you tell if you have caterpillars? The main way is to examine the leaves on your plants for holes. Caterpillars love to munch through leaves.

Saddleback caterpillar

The saddleback caterpillar, which is the larval form of a fuzzy dark brown moth, looks just like it sounds, like a beautiful furry brown saddle with a lime green blanket over the top. Fully grown saddlebacks get to be about 2 cm long, but they pack a punch. Both ends of the saddle and a row along each side of the insect are covered with stinging hairs that when touched can break off and embed themselves into the skin. These caterpillars love to feed on maples, hibiscus, palms and crape myrtle, according to the University of Florida/Institute of Food & Agricultural Sciences.

Puss caterpillar/Southern Flannel Moth

UF/IFAS warns that the Puss caterpillar looks hairy and soft, like a miniature toupee, which is why so many people try to touch them or pick them up, but don’t. Beneath the soft hairs are stiff spines attached to poison glands, which can break off and cause severe pain when embedded in your skin. Puss caterpillars get to be 2.5 cm long and are covered in gray and brown hairs. They love to feed on citrus, oak, and elm trees.

Io Moth caterpillar

Io moth caterpillars are pale green with a red and white stripe down the length of their bodies. These caterpillars are longer than the others at 6.5 cm. People should be careful not to touch the yellow or green bulbs tipped in black that protrude from the back end of the io moth caterpillar because they have stinging spines that can break off under the skin causing burning and itching. These caterpillars love to feed on hibiscus, elms, maples, wisteria, roses, azaleas, and willows.

Hag caterpillar

The Hag caterpillar looks like something straight out of Harry Potter’s monster manual. They come in various shades of brown and have curved spines, covered in hairs that are attached to toxin glands at the base. Touching the spines can cause itching, redness, burning, stinging, and inflammation, according to the University of Florida. Hag caterpillars like to feed on woody plants such as dogwood, apple, and oak.

What can you do if you are stung by one?

The first thing someone should do if they touch a poisonous caterpillar is to place tape over the affected area to remove the spines. Continue to place new pieces of sticky tape on the area until you believe the stickers are all gone. Then you should wash the area thoroughly with soap and water. If it itches, try putting hydrocortisone cream or a paste made from water and baking soda on the area. If that doesn’t work, take an antihistamine or use an antihistamine cream. If the area blisters up, seek out medical help, according to Poison Control.

Coastal Lawn & Pest is the premier lawn and pest control service in Southwest Florida, and while we don’t specialize in poisonous caterpillars, we can certainly help you eradicate other garden pests that can destroy your grass. Give us a call for a free estimate today.