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 arbusculoides Salix arbusculoides Salix arbusculoides is a species of flowering plant in the willow family known by the common name littletree willow. It is native to northern North America, where its distribution extends across Alaska and most of Canada. This willow is a shrub or tree growing up to 9 meters tall. It has many branches with smooth gray or reddish brown bark. The leaves are up to 7.5 centimeters long and often have a thin coat of hairs on the undersides. Immature leaves have thicker coats of hair and are paler and yellowish in color. The leaves have toothed edges