Arnica longifolia is a North American species of arnica in the sunflower family, known by the common names seep-spring arnica,Great Basin Wildflowers, Laird R. Blackwell, 2006, Morris Book Publishing LLC., longleaf arnica and spearleaf arnica.Calflora taxon report, University of California, Arnica longifolia D. Eaton longleaf arnica, seep spring arnica This flowering perennial is native to the forests of western Canada (British Columbia + Alberta) and the western United States (Rocky Mountains, Cascades, Coast Ranges, Sierra Nevada and other mountains of California, Oregon, Washington, Idaho, Nevada, Utah, Wyoming, Colorado, and Montana).Biota of North America Program 2014 county distribution map

Description Arnica longifolia is a rhizomatous plant forming large bunching patches of groundcover in moist, cool areas. The foliage is rough, mint-green, and sometimes sticky with glandular secretions. The stems are erect and bear daisylike flower heads with a diameter of 2 cm, with deep yellow ray florets and yellow to reddish or orange disc florets. The fruit is a reddish achene with a small pappus.Flora of North America Vol. 21 Page 374 Spearleaf arnica Arnica longifolia D. C. Eaton in S. Watson, Botany (Fortieth Parallel). 186. 1871.

References

External links Jepson Manual Treatment United States Department of Agriculture Plants Profile