Streambank Arnica
Arnica amplexicaluis Nutt.
Perennial from rather course, stems upright, usually unbranched, up to 2 1/2 feet tall, glandular and hairy. Leave mostly 5-12 in pairs, lanceolate to narrowly ovate up to 4 1/2 inches long. not much reduced upwards. Pale yellow flowers crowded into heads up to 2 inches across, consisting of 8-14 rays and a yellow disk.. Flowers in July and August. Grows along stream banks and moist woods, 1600-3200 mountain elevation. Reported by Cronquist in southeast Idaho in the Bear River Range.