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 matsudana female catkins on separate trees. The leaves are narrow, light green, around 4–10 cm long and 1–2 cm broad. The flowers are borne in catkins produced early in the spring The "Flora of China" recognizes three varieties within the species "Salix matsudana:" Many botanists, notably the Russian willow expert Alexei Konstantinovich Skvortsov, treat "Salix matsudana" as a synonym of the Peking willow "Salix babylonica", which, despite its botanical name, is also native to northern China. The only reported difference between the two is that "S. matsudana" has two nectaries in each female flower, whereas "S. babylonica" has only one; however