Arnica, a genus of perennial herbs native to Asia, Europe, and North America. There are about 10 species. The plants are usually between six inches (15 cm) and two feet (60 cm) in height. They have a cluster of leaves at the base of the stem and yellow flowers that resemble those of the daisy. Arnicas are not commonly cultivated in the United States, although they are suited for garden borders and rock gardens. At one time a tincture made from the dried flower heads of one species of arnica was popular as a medicine to relieve the pain of sprains and bruises.
Arnica montana is the species once used in medicine. The genus Arnica belongs to the composite family, Compositae or Asteraceae.Arnicas are perennial herbs with yellow flowers and a cluster of leaves at the base of the stem.