Willow are very cross-compatible, and numerous hybrids occur, both naturally and in cultivation. A well-known ornamental example is the weeping willow ("Salix × sepulcralis"), which is a hybrid of Peking willow ("Salix babylonica") from China and white willow ("Salix alba") from Europe. The hybrid cultivar 'Boydii' has gained the Royal Horticultural Society's Award of Garden Merit. Numerous cultivars of "Salix" L. have been developed and named over the centuries. New selections of cultivars with superior technical and ornamental characteristics have been chosen deliberately and applied to various purposes. Most recently, "Salix" has become an important source for bioenergy production and for
Salix bonplandiana Occidental cordillera northwest to southwest Durango. "S. taxifolia" occurs west of the Occidental cordillera in the south Pacific Coast north to southern Sinaloa–southwest Durango. "B. bonplandiana" has a few locales on the Mexican Plateau, (with both occurring in central Chihuahua, west of Chihuahua, Chihuahua). Other minor locale differences occur in central New Mexico, far west Texas, Coahuila, Nuevo Leon, and Tamaulipas. Spanish: Salix bonplandiana Salix bonplandiana (Bonpland willow), (Span.: "ahuejote", "sauce", "ahujote", and "huejote"), is a perennial species of willow tree native to southern and southwest Mexico and extending into central Guatemala; in western Mexico it is a tree of