Arnica griscomii

Fernald

Rhodora 26: 105, plate 143, fig. 7. 1924

Common names: Snow arnica
Synonyms: Arnica louiseana subsp. griscomii (Fernald) Maguire
Treatment appears in FNA Volume 21. Treatment on page 371. Mentioned on page 368.
Plants 5–40 cm. Stems usually simple, rarely branched. Leaves 1–4 pairs, mostly cauline; petiolate; blades elliptic, lanceolate, oblanceolate, ovate, or spatulate, 1.2–10 × 0.5–3.5 cm, margins usually denticulate to dentate, rarely entire, apices acute to obtuse or abruptly pointed, faces usually glabrous or sparingly hispidulous-puberulent, rarely stipitate-glandular. Heads usually 1, sometimes 2–3 (erect or nodding). Involucres hemispheric to campanulate-turbinate (bases sparsely to densely pilose, hairs white or yellow). Phyllaries 9–20, lanceolate to oblanceolate, not stipitate-glandular. Ray florets 6–17; corollas yellow. Disc florets: corollas yellow; anthers yellow. Cypselae brown, 2.5–6 mm, abaxially glabrous, adaxially sparsely hirsute or glabrous throughout, rarely glandular; pappi white, bristles barbellate.

Distribution

V21-925-distribution-map.gif

North America, Asia (e Russia).

Discussion

Subspecies 2 (2 in the flora).

References

None.

Key

1 Involucre bases sparsely to moderately white-pilose; Newfoundland, Québec Arnica griscomii subsp. griscomii
1 Involucre bases densely yellow-pilose; w North-west Territories to n British Columbia, Alaska Arnica griscomii subsp. frigida