They are mainly black with a red crest, and have a white line down the sides of the throat. They show white on the wings in flight. The flight of these birds is strong and direct but has an undulating quality, similar to the relatively unique flight-style of all woodpeckers. Adult males have a red line from the bill to the throat, in adult females these are black.
These birds mainly eat insects, especially carpenter ants and wood-boring beetle larvae. They also eat fruits, nuts, and berries, including poison ivy berries. Pileated Woodpeckers will often chip out large and roughly rectangular holes in trees while searching out insects, especially ant galleries. They also will lap up ants by reaching with their long tongue into crevices. They are self-assured on the vertical surfaces of large trees but can seem awkward while feeding on small branches and vines. Pileated woodpeckers may also forage on or near the ground, especially around fallen, dead trees, which can contain a smorgasbord of insect life. They may forage around the sides of human homes or even cars and can occasionally be attracted to suet-type feeders. Although they are less likely feeder visitors than smaller woodpeckers, Pileateds may regularly be attracted to them in areas experiencing harsh winter conditions.
Usually, Pileated Woodpeckers excavate their large nests in the cavities of dead trees. Woodpeckers make such large holes in dead trees that the holes can cause a small tree to break in half. The roost of a Pileated Woodpecker usually has multiple entrance holes. Pileated Woodpeckers raise their young every year in a hole in a tree. In April, the hole made by the male attracts a female for mating and raising their young. Once the brood is raised, the Pileated Woodpeckers abandon the hole and will not use it the next year. When abandoned, these holes—made similarly by all woodpeckers—provide good homes in future years for many forest song birds and a wide variety of other animals. Owls and tree-nesting ducks may largely rely on holes made by Pileateds in which to lay their nests. Even mammals such as raccoons may use them. Other woodpeckers and smaller birds such as wrens may be attracted to Pileated holes to feed on the insects found in them. Ecologically, the entire woodpecker family is important to the well being of many other bird species. The Pileated Woodpecker will also nest in nest boxes about 4.6 m (15 ft) off the ground.