Key Points
- Most of the caterpillars that are called stinging caterpillars don't sting like wasps or hornets do. They have hairs or spines that sometimes have a poison gland at the base.
- When touched, the hairs break off and the poison is injected, causing an inflammation of the skin and a burning sensation that may feel like a bee sting.
- The reaction can be more severe if the eyes, nose or mouth are affected.
- Stinging caterpillars are not that commonly found around home and yards. Most feed on native trees and shrubs in wooded areas.
The saddleback caterpillar is not fuzzy, but has a striking green saddlecloth on its back with a purplish brown saddle in the middle. It also has irritating spines.
The puss caterpillar (below) is about 1 inch long, when fully grown, furry, and gray to reddish brown in color.
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The Io moth caterpillar is about 2 1/2 inches long when fully grown. It is bright green with red and white stripes and four rows of short, stinging spines.
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It is not necessary to control any of these caterpillars. They cause minimal damage to trees and shrubs.
Rev. 2020