Pussy willow is a name given to many of the smaller species of the genus Salix (willows and sallows) when their furry catkins are young in early spring. These species include (among many others):

• Goat willow or goat sallow (Salix caprea), a small tree native to northern Europe and northwest Asia.
• Grey willow or grey sallow (Salix cinerea), a small tree native to northern Europe.
• American pussy willow (Salix discolor), native to northern North America.

Before the male catkins of these species come into full flower they are covered in fine, greyish fur, leading to a fancied likeness to tiny cats, also known as “pussies”. The catkins appear long before the leaves, and are one of the earliest signs of spring. At other times of year trees of most of these species are usually known by their ordinary names.