Poisonous Caterpillars

— Written By NC Cooperative Extension


Last Monday a lady and her young daughter came into my office wanting me to identify a bug. Little did I know that this bug had sent the young daughter to the hospital last week. The bug in question was a Puss caterpillar. These folks like most people did not know that limited numbers of caterpillars are poisonous. Now I am not saying this to scare or frighten anyone, these caterpillars are very rare and are generally seldom seen.

Puss caterpillars appear harmless. They are teardrop-shaped with long silky hair that resembles a tuft of cotton or fur. They range in color from yellow/grey to reddish brown. The head and legs are not visible. These caterpillars feed on common trees and shrubs including: oak, wild cherry, pecan, plum, maple and elm. Unfortunately, the Puss caterpillar is one of the most toxic caterpillars found in North America. Hidden beneath the silky hair of the caterpillar are venomous setae (poison glands). When someone comes in contact with a Puss caterpillar several reactions may occur: intense burning, inflammation and development of pustules and lesions, numbness and swelling, intense pain and nausea. The severity is greatly effected by a persons tolerance to the sting. To some it may be no worse than a bee sting, whereas to others immediate medical attention may be needed.

Another venomous caterpillar that I have seen in our county is the Saddleback caterpillar. These caterpillars have a purple/brown colored head and rear. Their midsection is lime green with one brown patch on its midsection which gives the appearance of a saddle and a blanket. In addition to the lime green saddle on their back the also have "horns" on their head and rear which makes them very easy to identify. These caterpillars feed on the same broadleaf vegetation as the Puss caterpillar. They are often found in late summer and fall. The sting of the Saddleback caterpillar is painful, but usually the reaction is less severe than that of the Puss caterpillar.

Once again, this article was not written to scare or frighten anyone I simply wanted to inform people of these caterpillars. If you do come in contact with one of these caterpillars, treat it like a bee sting and if it starts to worsen seek medical help. For more information on stinging caterpillars you may call me at the Cleveland County Cooperative Extension office at 704-482-4365.

This article was written by Daniel Shires, Extension Agent – Horticulture, for these and other Lawn & Garden type questions call 704-482-4365 or e-mail Daniel Shires.

Posted on Sep 29, 2006
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