A deciduous tree and shrub of the genus Salix, order Salicales, common along streams and in wet places in the United States, Europe, and China. The twigs are often yellow-green and bear alternate leaves which are characteristically long, narrow, and pointed, usually with fine teeth along the margins. Flowers occur in catkins. The fruit contains several silky seeds.

Willow lumber is used for fuel and in making charcoal, excelsior, ball bats, boxes, crates, boats, waterwheels, and wicker furniture. The tough, pliable shoots of many species are used to make baskets; the bark of other species is used for tanning. Willows are of great value in checking soil erosion. A few species are ornamental shade trees.