Arnica is a low-growing perennial with daisy-like flowers that have a yellow center and lighter-colored petals. The flowers are separated from the receptacles and the bract so that arnica herb consists of the florets. Bristly white hairs attached to the ovary give the herb a somewhat fuzzy appearance. Arnica is most widely used in topical skin applications.
To make an herbal compress, pour 1/4 cup boiling water over 2 teaspoons of arnica and steep for 10 to 15 minutes. Strain and dip cotton or wool cloth or gauze in the liquid.