American Dagger Moth (Acronicta americana) Caterpillar
American dagger moths (Acronicta americana) are a fairly nondescript gray moth, perfect for camouflaging itself against mottled tree trunks during the day (see this BugGuide link for pictures of adult American dagger moths). The caterpillar of the species, on the other hand, is one of the fluffiest larval lepidopterans I’ve ever encountered. It is covered in dense hairs, called setae, which are yellow in younger instars and turn white as the caterpillar ages. There are also longer pairs of black…