Salix babylonica a gold-yellow in autumn. The flowers are arranged in catkins produced early in the spring; it is dioecious, with the male and female catkins on separate trees. "Salix babylonica" was described and named scientifically by Carolus Linnaeus in 1736, who knew the species as the pendulous-branched ("weeping") variant then recently introduced into the Clifford garden in Hartekamp in The Netherlands. Early Chinese cultivar selections include the original weeping willow, "Salix babylonica" 'Pendula', in which the branches and twigs are strongly pendulous, which was presumably spread along ancient trade routes. These distinctive trees were subsequently introduced into England from Aleppo in
Salix glauca Salix glauca Salix glauca is a species of flowering plant in the willow family known by the common names gray willow, gray-leaf willow, white willow, and glaucous willow. It is native to North America, where it occurs throughout much of Alaska, northern and western Canada, and the contiguous United States south through the Rocky Mountains to northern New Mexico. It can also be found in Greenland, northwestern Europe, and Siberia. This willow is usually a shrub growing up to tall, but in appropriate habitat it becomes a tree up to tall. The smooth gray bark becomes furrowed with age. The