willow

Any shrub or tree of the genus Salix, family Salicaceae, native mostly to northern temperate regions, and common in lowland and marshy areas. Willows are valued as ornamentals and for their shade, erosion control, and timber. Certain species yield salicin, the source of salicylic acid used in pain relievers. All species have alternate, usually narrow leaves, catkins, and seeds with long, silky hairs. Pussy willows, the male form of several shrubby species, have woolly catkins that form before the leaves appear and are considered one of the first signs of spring. Weeping willows have long drooping branches and leaves. Several species grow as small matted woody plants on the tundra.

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