Spruce budworm, destructive insect in the Tortricidae family. This insect (Choristoneura fumiferana) lives in the northern United States and Canada. It destroys evergreen trees—particularly the spruce—by feeding on the needles and pollen each spring for 3–6 years while in the caterpillar stage. Each summer the small moths that display dark markings lay their eggs in the trees, which in turn spin cocoons. Methods of forest management and other biological controls check the spread of these insects more effectively than do pesticides. In the past devastating outbreaks of these pests have occurred approximately once every half century.