Fir Tussock Caterpillar

We recently received five photos from a reader containing images of different caterpillars. He hopes we will identify them. We will be writing an article for each of these different organisms! This is the third of the caterpillar posts.

This caterpillar has two distinct black antennas and a tail, as well as long white hairs surrounding its body. The most prominent features are the 4 yellow horns on the anterior end. We believe this is an Orgyia detrital, or a fir tussock caterpillar. There are several different species of Orgyia moths and caterpillars. However many species show the four prominent bumps, including this one. While this caterpillar is very interesting to look at, if you touch it you might feel like you are touching fiberglass, and it may even leave you with a painful rash. These caterpillars and moths are distributed around some parts of Canada and the United States. Fir Tussock caterpillars eat the foliage of both deciduous and coniferous trees.

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Overall, we think that the fir tussock moth caterpillars are very intriguing, but we hope we don’t accidentally touch one!

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Caterpillar Post 3- Fir Tussock Caterpillar
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Caterpillar Post 3- Fir Tussock Caterpillar
We recently received five photos from a reader containing images of different caterpillars, this is a fir tussock.

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