Arnica viscosa

A. Gray

Proc. Amer. Acad. Arts 13: 374. 1878.

Common names: Mt. Shasta arnica
Endemic
Synonyms: Chrysopsis shastensis Jepson Raillardella paniculata Greene
Treatment appears in FNA Volume 21. Treatment on page 377. Mentioned on page 367.

Plants 20–50 cm. Stems branched (prominently ribbed, strongly stipitate-glandular; caudices woody). Leaves 5–10 pairs (main stems, 2–6 pairs on branches; basal withered by flowering), cauline; sessile; blades obovate-oblong to ovate-oblong, (1–)2–4(–5) × 1–3 cm, margins ± entire, apices acute, faces sparsely to densely pilose, densely stipitate-glandular. Heads 10–20. Involucres narrowly turbinate. Phyllaries 10–20, broadly lanceolate (stipitate-glandular). Ray florets 0. Disc florets 10–30; corollas cream; anthers yellow. Cypselae dark gray, 4.5–6.5 mm, stipitate-glandular; pappi usually white, rarely tawny, bristles barbellate to subplumose. 2n = 38.


Phenology: Flowering Aug–Sep.
Habitat: Open, rocky subalpine to alpine
Elevation: 1700–2500 m

Discussion

Selected References

None.

Lower Taxa

None.