A flowering plant about 18–60 cm (7.1–23.6 in) tall aromatic fragrant, perennial herb. Its basal green ovate-cilitate leaves with rounded tips are bright coloured and level to the ground. In addition, they are somewhat downy on their upper surface, veined and aggregated in rosettes. By contrast, the upper leaves are opposed, spear-shaped and smaller which is an exception within the Asteraceae.The main constituents of Arnica montana are essential oils, fatty acids, thymol, pseudoguaianolide sesquiterpene lactones and flavanone glycosides. Pseudoguaianolide sesquiterpenes constitute 0.2-0.8 % of the flower head of Arnica montana. They are the toxin helenalinand their fatty esters. Historically has been used as an herbal medicine. It has been used in herbal medicine for centuries for its restorative bloodflow and analgesic properties.
The flowering season is between May and August (Central Europe). The hairy flowers are composed of yellow disc florets in the center and orange-yellow ray florets at the external part. The achenes have a one-piece rough pappus which opens in dry conditions. Arnica montana is a hemicryptophyte, which helps the plant to survive the extreme overwintering condition of its habitat. In addition, Arnica forms rhizomes, which grow in a two year cycle: the rosette part grows at its front while its tail is slowy dying.