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 denticulata Salix denticulata Salix denticulata is a species of shrub or small tree in the family Salicaceae. It is a mountain species endemic to the Himalayan region. "Salix denticulata" can reach a height of . The shoots are downy when young. The dull green leaves are paler underneath, obovate, lanceolate or elliptic, with toothed margins, long, with very short petioles. Like all willows this species is dioecious. Male catkins are long, with yellow anthers, and female catkins long, lengthening to in fruit. The flowers bloom in April and May. "Salix denticulata" is native to the mountainous regions of central Asia, being