In this image you can see that the antlers still have their soft vellum covering. However,"by late August, a bull's antlers become hardened bone, having completed their remarkable annual growth. The velvet tissue that covered and nurtured the antlers as they grew has now dried tight to the rack and is no longer functional. Velvet shedding is usually quick, with even the biggest bulls stripping their racks within a day or two by rubbing and thrashing them on shrubs and evergreen saplings." -- Outdoor Canada.