Camphor is not confined to any one species or even genus of plants. Rather, it is widely recognized by the U.S. Pharmacopia in various species, and also in the roots of cinnamon, cassia, sassafras and ginger. The camphor of commerce is derived exclusively from the Laurus Camphora and the Dryobalanops Camphora and is obtained by sublimation of branches, trunk and roots followed by distillation.