Monday, September 26, 2016

Ever see a Saddleback caterpillar?


Most people know that bees, wasps, hornets and some ants can sting to defend themselves or their nests. Only a few people realize, usually from first hand experience, that handling some caterpillars can produce some painful results. Recognizing the few stinging caterpillar species, including the saddleback, may prevent irritating encounters.
  1. Saddleback Caterpillar

Saddleback Caterpillar Description

The saddleback caterpillar measures about an inch long, and has poisonous spines on four large projections (tubercles) and many smaller ones projecting from the sides of its body. The “saddle” consists of an oval purplish-brown spot in the middle of a green patch on the back. Here are more photos of the saddleback as well as other stinging caterpillars.
The saddleback caterpillar is a general feeder and is generally found on many hosts including corn foliage, apple, pear, cherry, rose, Pawpaw, basswood, chestnut, oak, plum and other trees in late summer.

Diagnosing and Treating Stings

Diagnosis is usually simple since a rash generally breaks out where the hairs or spines have made skin contact. Contacting the hollow poisonous hairs or spines (connected to underlying poison glands) causes a burning sensation and inflammation that can be as painful as a bee sting. The irritation can last for a day or two and may be accompanied by nausea during the first few hours. Usually the site of contact reddens and swells much like a bee sting.
Immediate application and repeated stripping with adhesive or transparent tape over the sting site may be helpful in removing broken hairs or spines. Washing the affected skin area thoroughly with soap and water may help remove irritating venom. Prompt application of an ice pack and a baking soda poultice should help reduce pain and swelling. Household analgesics, such as aspirin, appear to be ineffective for reducing pain and headache. However, oral administration of antihistamines may help relieve itching and burning. Topical corticosteriods may reduce the intensity of inflammatory reaction. Desoximetasone gel applied twice daily to affected areas may also help. Prompt referral to and treatment by a physician should be made when severe reactions are evident. Very young, aged or unhealthy persons are more likely to suffer severe reaction symptoms.

Sting Prevention

Occasionally, these stinging hair caterpillars may drop out of trees onto people, crawl into clothing on the ground, occur on outdoor furniture or sting when brushed against on plant foliage. Be careful when attempting to brush them off. Never swat or crush by hand. Remove them carefully and slowly with a stick or other object.
Individuals, especially children, should be cautioned about handling or playing with any colorful, hairy-like, fuzzy caterpillars since it is sometimes difficult to distinguish between harmless and venomous insect larvae. Never handpick these hairy, fuzzy or spiny caterpillars except with heavy leather gloves if necessary. Wear long sleeve shirts, trousers and gloves when harvesting sweet corn or working in the landscape in late-summer and early-autumn to reduce possible stings.

Chemical Control

Usually, these stinging hair caterpillars do not occur in sufficient numbers to warrant the use of pesticide sprays. Should potential hazards exist around residences or schools, infested shrubs and trees may be sprayed to reduce or eliminate these caterpillars. Sprays of carbaryl (Sevin), or Bacillus thuringiensis (Biotrol WP, Sok-bt, or Thuricide) as well as various pyrethroids (bifenthrin, cyfluthrin, cypermethrin, deltamethrin, lambda-cyhalothin, permethrin and tralomethrin) in formulations labeled for bushes, shrubs and trees, can be helpful, if practical. Be sure to read the label, follow directions and safety precautions.


  1. I've been the 'victim' of some pretty nasty caterpillars down here in Texas (not saddlebacks, however). They look like the Northern bag caterpillars, and some years they are everywhere. I picked up a piece of plywood and held it against my 'belly', not knowing they were on the reverse side. I had a perfect imprint of 5 caterpillars on my abdomen. Hurt for a couple of days. I was also nauseated for that whole time. It took a couple weeks for the sting marks to fade! Buckmoth caterpillar. Haven't seen any bad ones this year!! Hope you can steer clear of them.

    When I was a kid I don't remember ever getting stung by a caterpillar.

    Fair Winds,

    Cap'n Jan

    1. Good heavens, Cap'n Jan - that's just awful! I even hate to get bit by a skeeter - I just itch and itch and where they bite, the whole area swells!

    2. Hey Chickenmom! Just a lesson I learned when I moved to Texas - almost everything here bites, stings, sticks, scratches, or just makes you itch, or an infinite combination of the above.

      I'll say one of the most prolific nasties we HAD was fire-ants. They are all gone now, been driven out by Argentinian Crazy-ants. Doesn't seem likely as fire-ants are so war-like, but, I think the Argentines just keep sending in troops and eventually 'win'. A war of attrition against the fast breeders wins every time. Any road, we haven't seen a fire-ant mound in about 3 years now. We were at war with them full time for 20 years or more. Talk about a horror show! If you are standing near their mound, they secretly cover you feet and legs, and then send a chemical signal where they all start stinging. They don't bite, they STING! And the sting is bad enough that it can hospitalize some folks. My first lesson was about 100 welts that I had to tame with cortisone.

      Anyway, gone on too long! But I love your little interest stories!! Your place looks great and such fun!!! I have a tractor too - small Kubota BX-25, front end loader and back hoe. The most USEFUL thing I have ever purchased! I'll bet your husband feels that way about his tractor!

      -Cap'n Jan

    3. Whew! Glad we don't have those nasty critters here in Joisey! Lots of yellow jackets and mosquitoes, though. My arms all all bitten by them.
      Apple cider vinegar seems to help the itch for some strange reason. Hubby just loves his - it does the work of an extra three men around here!

  2. what is the bug that arises from this caterpillar?

    1. It's definitely not as colorful, Deborah - you can it see here:

  3. Did some research to find out where they live and copied this:


    1. Thanks, T.W. - that was a good article! Haven't seen any here in Coopville. And I don't want to! :o)