In summer, they are reddish-brown to tan above; the winter the colors are grayish to grayish brown. Fawns are reddish, brown or reddish-yellow spotted with white; they lose their spots and acquire uniform coloration at 3–5 months of age. Antlers normally occur only in males and are formed and shed each year. Antler growth starts in April or May. During the growth period, the soft skin and short hair covering the antlers have a plush quality, giving this stage the name of "velvet." The white-tailed deer is aptly named because the white undersurface of its flaglike tail is about all that we see in the fleeting glimpse we get as it bounds across an opening in the woods.