Salix mucronata (Cape willow) is a fast-growing, semi-deciduous tree found along riverbanks across KwaZulu-Natal, Free State, Gauteng, Mpumalanga, Limpopo and North West. In garden settings it reaches a mature height around 5 m, while specimens in their natural riverine habitat can grow considerably taller, up to around 15 m. The tree has an open crown and softly drooping branches that give it a weeping habit.

The leaves are simple and alternate, tapering at both ends, dark green above and paler beneath, with margins that are smooth or lightly serrated. Even a slight breeze sets the foliage moving. Flowering happens in early spring, from August into September. The species is dioecious, meaning male and female flowers appear on separate trees. Male spikes are dense, yellow, and up to 50 mm long, while female spikes are shorter, thicker, and greenish.

Cape willow is hardy and fast-growing, tolerating both frost and drought, though it performs best with reliable moisture. Its root system is vigorous and actively seeks out water, which makes it a poor choice near pipes, foundations, or paving. The vigorous roots help stabilise eroding banks and buffer water sources from livestock damage.

The tree also has a longstanding place in traditional medicine. Its roots, bark, and leaves contain salicin, the compound from which aspirin was originally derived, and it has long been used to treat headaches, fevers, and inflammation.

Ecologically, it serves as a larval host plant for the common orange-and-black (Acraea) butterfly and its leaves are readily browsed by livestock. When planted near water, it offers cooling shade, draws butterflies and other beneficial insects.