Salix richardsonii is a species of flowering plant in the Salicaceae, or willow family. It is known by the common names Richardson's willow and woolly willow. It is native to Russia and northern North America, where it occurs in Alaska and northern Canada. This plant provides food for many animals, such as moose, caribou, and beavers. The thickets provide cover, and beavers use the branches to build their dams. Thickets of the plant on streambanks allow the water to undercut the bank, providing overhangs for fish to hide under.