The evergreen bagworm (Thyridopteryx ephemeraeformis), commonly known as bagworm, eastern bagworm, common bagworm, common basket worm, or North American bagworm, is a moth that spins its cocoon in its larval life, decorating it with bits of plant material from the trees on which it feeds. Arborvitae and red cedar are the favored host trees of the evergreen bagworm, but cypress, juniper, pine, spruce, apple, birch, black locust, elm, maple, poplar, oak, sycamore, willow, and over 100 other species are also attacked. Leaves and buds are both fair game for food.