Fawns consume mothers' milk and are usually weaned by the time they are 3 months old. The green vegetation is most important to mature deer. Antlers are different from horns. Antlers are solid, composed of blood, protein, and minerals, and dropped off late each winter. Horns are composed of dense hair and retained through the life of animals like bighorn sheep and goats.
Antlers begin growing in the spring of each year when the days begin getting longer.
While growing, they are soft and tender and covered with a velvet material. The velvet loosens and the bucks rub it off on small trees and bushes. They keep the hard, white-colored antlers through the winter. Bucks may use antlers to leave visible rubs on trees or fight with other bucks to establish dominance. Antlers get larger each year, as the buck grows older.