Salix babylonica but beyond China, it has not generally been as successfully cultivated as some of its hybrid derivatives, being sensitive to late-spring frosts. In the more humid climates of much of Europe and eastern North America, it is susceptible to a canker disease, willow anthracnose ("Marssonina salicicola"), which makes infected trees very short-lived and unsightly. "Salix babylonica" (Babylon willow) has many cultivars, including: Various cultivars of "Salix matsudana" (Chinese willow) are now often included within "Salix babylonica", treated more broadly, including: Yet other weeping willow cultivars are derived from interspecific "Salix" hybrids, including "S. babylonica" in their parentage. The most widely
Salix myrtilloides new leaves appear. The leaves resemble bilberry ("Vaccinium uliginosum") leaves in shape, hence the name in the Finnish and Swedish languages, which translates as "bog bilberry willow". A very similar, closely related species, "Salix pedicellaris" (bog willow), occurs in northern North America; it is classified as a variety of swamp willow "S. myrtilloides" var. "pedicellaris" by some botanists. Salix myrtilloides Salix myrtilloides, the swamp willow, is a willow native to boglands in cool temperate to subarctic regions of northeastern Europe and northern Asia from central Norway and Poland eastwards to the Pacific Ocean coasts, with isolated populations further south in