It is a medium to large deciduous tree growing up to 10-30 m tall, with a trunk up to 1 m in diameter and an irregular, often oblique crown. The bark is grey-brown and deeply fissured in older trees. The leaves are more paler than most other willows because they are covered with very thin, silky white hairs, especially on the underside; they are 5-10 cm long and 0.5-1.5 cm wide. It is dioecious with male and female flowers on separate trees; male flowers are 4-5 cm long, female flowers are 3-4 cm long during pollination and become longer as the fruit ripens. When ripe in mid-summer, the female flowers contain numerous small (4 mm) capsules, each of which contains numerous small seeds embedded in silky white hairs that help disperse the wind.

Other compounds: flavones, flavonols, flavanones, dihydroflavonols, isoflavones, chalcones, dihydrochalcones, flavan-3-ols and anthocyanins