Arnica sororia
| Arnica sororia | |
|---|---|
 | |
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Tribe: | Heliantheae |
| Genus: | Arnica |
| Species: | A. sororia |
| Binomial name | |
| Arnica sororia Greene | |
Arnica sororia is a North American species of arnica known by the common name twin arnica.[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]
Arnica sororia is a rhizomatous perennial herb producing one or more hairy, glandular stems 10 to 50 centimeters tall. There are several pairs of broadly lance-shaped leaves along the stem, the lower ones borne on petioles. Leaves may reach up to 14 centimeters long.[4]
The inflorescence holds one to five daisy-like flower heads lined with phyllaries coated in glandular hairs. The flower head has a center of glandular yellow disc florets and a fringe of yellow ray florets. The fruit is an achene a few millimeters long with a white pappus.[4]
References
External links
- Jepson Manual Treatment
- United States Department of Agriculture Plants Profile
- Calphotos Photo gallery, University of California