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 bonplandiana Salix bonplandiana Salix bonplandiana (Bonpland willow), (Span.: "ahuejote", "sauce", "ahujote", and "huejote"), is a perennial species of willow tree native to southern and southwest Mexico and extending into central Guatemala; in western Mexico it is a tree of the Sierra Madre Occidental cordillera, but also occurring in other small locales, for example Baja California Sur, northern Sonora, San Luis Potosi, etc. A core disjunct area occurs in central and southeast Arizona, in advantageous locales, especially associated with higher elevations and water. In Mexico, the Bonpland willow is associated with the Pacific Coast, and in southern Mexico, the range extends into