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
Micrurapteryx salicifoliella arbusculoides", "Salix babylonica", "Salix bebbiana", "Salix brachycarpa", "Salix exigua", "Salix glauca", "Salix integra", "Salix interior", "Salix lasiandra", "Salix longifolia", "Salix monticola", "Salix novae-angliae", "Salix planifolia" and "Salix scouleriana"). They mine the leaves of their host plant. The mine is found on the upperside of the leaf, sometimes covering the entire leaf area. It is a flat upperside blotch, initially greenish but later turning brown. The larva chews a hole through the bottom of the mine and exits through it to pupate. The cocoon is often spun on the upperside of a leaf, parallel to its long axis. Micrurapteryx salicifoliella Micrurapteryx