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Douglas-Fir Tussock Moth Caterpillar

    Caterpillars of Douglas-fir tussock moth are very hairy. The hairs on the caterpillars as well as their egg masses and cocoons may cause allergic reactions to some people, called “tussockosis.” Itching is the most common complaint, but adverse health effects can include rashes (with welts or blisters), watery eyes, runny nose, cough and, less commonly, shortness of breath, wheezing, and chest tightness.


    One generation a year; the insect overwinters in an egg mass; caterpillars hatch from eggs at bud break and feed on needles throughout the early to mid-summer; adult male moths fly during the mid-summer. If you are camping the Sage Hen Reservoir area you will most likely see tussock moth’s in and around the campgrounds. If you have any questions regarding this outbreak, please call the Emmett District office 208-365-7000.    

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