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
Caloptilia stigmatella cone. Pupation takes place in a shiny cocoon at the underside of the leaf. Caloptilia stigmatella Caloptilia stigmatella is a moth of the Gracillariidae family. It is known from the Holarctic Region, including all of Europe (except the Balkan Peninsula). The wingspan is . Adults are on wing in late June and July, and again from September onwards. The larvae feed on "Myrica gale", "Populus alba", "Populus candicans", "Populus canescens", "Populus nigra", "Populus tremula", "Salix alba", "Salix aurita", "Salix babylonica", "Salix cinerea", "Salix dasyclados", "Salix elaeagnos", "Salix fragilis", "Salix glaucosericea", "Salix lanata", "Salix magnifica", "Salix myrsinifolia", "Salix pentandra", "Salix purpurea",