Arnica sororia

[1] It is native to Western Canada (British Columbia, Alberta, Saskatchewan) and the Western United States (Washington, Oregon, California, Nevada, Utah, Idaho, Montana, Wyoming, South Dakota).

[2] It grows in grasslands and in conifer forests,[3] as well as the sagebrush steppe.

[4] Arnica sororia is a rhizomatous perennial herb producing one or more hairy, glandular stems 10 to 50 centimeters (4 to 19+1⁄2 in) tall.

There are a few to several pairs of broadly lance-shaped leaves along the stem,[4] the lower ones borne on petioles.

[5] The inflorescence consists of a daisy-like flower head, rarely more than one per stem.