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 alba Pliny the Elder and others believed willow bark could ease aches and pains and reduce fevers. It has long been used in Europe and China for the attempted treatment of these conditions. This remedy is also mentioned in texts from ancient Egypt, Sumer, and Assyria. The first "clinical trial" was reported by Reverend Edward Stone, a vicar from Chipping Norton in Oxfordshire, England, in 1763 with a successful treatment of malarial fever with the willow bark. The bark is often macerated in ethanol to produce a tincture. The active extract of the bark, called salicin, after the Latin name "Salix",