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 bicolor Salix bicolor Salix bicolor is a species of flowering plant in the family Salicaceae (willows). "Salix bicolor" can reach a height of . This plant usually develop into a large shrub, but may grow as a multi branched tree of up to 4 m height. Branches are glabrous. brown-reddish or chestnut. Leaves are yellow-green, glabrous, elliptical or lanceolate with acute apex. They are long and wide. The catkins are produced in early spring, before the leaves. They reach 3 × 1 cm, on long peduncles with lanceolate bracts. Like all willows this species is dioecious. Flowers bloom from May to