The genus name Salix is the old Latin name for willow; the species name caprea is the Latin for goat, its foliage browsed by them on the Continent. The earliest reference to this is in the herbal by Hieronymus Bock which shows the species being eaten by a goat.
The female flowers are similarly simple. They too have a hairy bract at the base and a small nectary on the inside surface. The ovary is has a short stalk (i.e. the ovary is stipitate). It is hairy and asymmetrical at the base and contains two cavities, each containing several ovules. At the tip of the ovary are four stigmas which are shrivelled and brown in the photos.
The floral formula is
This shows that the sexes are separate. There is a single bract and the calyx and corolla are absent. The male flowers have two anthers and the female flowers two carpels which are fused together into a single ovary. The ovary is superior.