The adult Acorn Woodpecker has a brownish-black head, back, wings and tail, white forehead, throat, belly and rump. There is a small part on their backs were there are some green feathers. The adult male has a red cap starting at the forehead, whereas females have a black area between the forehead and the cap.
Fun Fact Acorn Woodpeckers have a call that is almost like they are laughing, as parodied by the cartoon character "Woody Woodpecker".