Pure Populus nigra absolute. Poplar bud absolute is extracted from the buds of the Populus nigra, commonly known as black poplar, a species of cottonwood poplar native to Europe, southwest and central Asia, and northwest Africa. The buds produce a sticky fragrant resin that protects the tree over the winter and are harvested in early spring. The resin of several North American species of poplar has been used historically by North America’s indigenous population for many healing purposes. Christi