rub

A mark left on a tree trunk or sapling by a deer or elk rubbing its antlers against the bark — stripping it away, polishing the wood beneath, and depositing scent from the forehead glands. Rubs appear in early autumn when bucks shed their velvet, and fresh rubs are one of the most reliable signs of a buck's presence and size. A rub on a sapling the diameter of a thumb was made by a small deer; a rub on a tree the diameter of a forearm was not. Bears also rub trees — standing upright and working their back against the bark, leaving behind coarse hair and a polished, resinous patch that can persist for years.