Nest: These woodpeckers prefer living pines infected with red heart rot for nesting. These trees have a soft, easily excavated interior with a living exterior, leaving the tree less susceptible to destruction by fire than a dead tree. Cavities can often be reused for at least 20 years and for several years by the same pair (Ligon 1971). The height of cavity is influenced by the location of red heart infection and the height and density of undergrowth (Crosby 1971). The majority of cavities face west, and, when found in leaning trees, are generally on the low side (Beckett 1971, Baker 1971). Food: Insects make up the major portion of the diet of red-cockaded woodpeckers. Beal (1911) and Beal et al. (1916) examined 99 stomachs and found 86 percent insects and 14 percent vegetable matter, mostly mast. Beetle larvae (16 percent) and ants made up an important part of the year-round diet. The corn earworm can be a major food source during several weeks where conditions are suitable (Ward 1930). Plant material recorded being eaten includes wax myrtle, magnolia, poison ivy, wild grape, pokeberry, blueberry, wild cherry, black gum, and pecan (Beal 1911, Baker 1971, Ligon 1971). White-headed woodpecker _Picoides albolarvatus_ L 7¾″ [Illustration] Habitat: Open ponderosa pine forest from Washington to central California is the primary habitat of the white-headed woodpecker, but it also occurs in sugar pine, Jeffrey pine, and red and white fir forests (Grinnell and Miller 1944). Nest: This woodpecker seems to prefer dead pines, but nests have also been found in live and dead fir, oak, and aspen. White-headed woodpeckers usually excavate a new nest cavity every year and often excavate several holes before selecting one to nest in (Bent 1939). Average nest height is 8 feet above ground. Food: White-headed woodpeckers feed primarily on pine seeds during the winter and early spring, and on insects during the summer. Tevis (1953) determined that 60 percent of the annual diet was pine seeds and 40 percent was insects. Ants made up half of the insect food; other insects taken were woodboring beetles, spiders, and fly larvae (Beal 1911, Grinnell and Storer 1924, Ligon 1973). Black-backed three-toed woodpecker _Picoides arcticus_ L 8″ [Illustration] Habitat: The conifer forests of the north are preferred, but this three-toed woodpecker is not abundant even in its favorite habitat. Forest types include mixed conifer, lodgepole pine, white fir, subalpine fir, tamarack swamps, boreal spruce-balsam fir, Douglas-fir, and mixed hardwood-conifer. Nest: This species usually excavates its cavities in snags or live trees with dead heartwood, especially in areas that have been burned or logged (Bent 1939). Nests are usually in spruce, balsam fir, pines, or Douglas-fir, although maple, birch, and cedar have been used.