Salix serpillifolia

Salix serpillifolia or Salix serpyllifolia is a species of flowering plant in the family Salicaceae.

Description
Salix serpillifolia, also known as thyme-leaved willow, can reach a height of 10 - 30 mm and a length of about 20 cm. This plant develop woody, dark brown, longitudinally striated, creeping stems. The leaves are tiny, simple, subsessile, spathulate to obovate, without stipules. The upper side is glabrous, glossy dark green covered with a thin waxy layer. Like all willows this species is dioecious. Catkins appear after the leaves. They are about 5 mm long, with yellow anthers. Flowers bloom from May to August.

Distribution
It is present in mountains of southern Europe, from the Iberian Peninsula, the Alps and the Balkans.

Habitat
This species can be found in stony alpine turf, rock crevices and screes at elevation of 1700 - 3200 m above sea level.

Uses
Salix serpillifolia contains salicin, the source of salicylic acid in aspirin.