Question
Recently a Catawba worm landed on my neck. I immediately swiped it off but it left a very irritating rash. Is this normal? It happened last year on the other side of my neck. Are they poisonous?

Answer
Melissa,

Many moths have what are called "urticating" hairs on the larvae, or caterpillars. These hairs cause irritation if touched or rubbed onto skin. However, I've found no reference to urticating hairs in catawba worms. So my guess is that either it was another type of caterpillar, one that has urticating hairs, or the rash was caused by something else.

Post a follow up if you have questions. You might also google the term "urticating hairs".

Jack DeAngelis
http://www.livingwithbugs.com