Willow, common name for about 300 species of trees of the genus Salix, which occur from the tropics to the Arctic. The leaves are generally swordlike, and male and female catkins are borne on separate plants. The willows of the temperate zone are large, but the dwarf willow, found beyond the tree lines of the Arctic, grows to only about 6 in (15.2 cm). The long, pliable twigs of some species are cut regularly for use in making wicker baskets and furniture. Other species are used for tannins or for their light and durable wood. The ornamental weeping willow is a native of China and southwest Asia.