Arnica mollis |
Arnica acaulis |
|
---|---|---|
cordilleran arnica, cordilleran leopardbane, hairy arnica |
common leopardbane |
|
Habit | Plants 15–70 cm. | Plants 20–80 cm. |
Stems | (forming clumps) simple or branched among heads. |
simple. |
Leaves | (2–)3(–4) pairs, mostly cauline (basal sometimes present); petiolate (petioles relatively short, broad-winged) or subsessile; blades broadly elliptic, lance-elliptic, or narrowly to broadly lanceolate, 4–20 × 1–4 cm, margins entire or irregularly denticulate, apices acute, faces sparsely to moderately hairy (hairs relatively short to long, stipitate glands or soft, silky). |
2–4(–6) pairs, nearly all basal; sessile; blades (with 3, 5, or 7 prominent, subparallel veins) broadly elliptic, ovate, or rhombic, 4–15 × 1.5–8 cm, margins mostly entire, apices mostly obtuse, faces hirsute and stipitate-glandular (cauline leaves 0 or 1–2, distalmost often alternate, much reduced). |
Involucres | hemispheric to campanulate. |
campanulate. |
Ray florets | 10–22; corollas yellow. |
10–16; corollas yellow. |
Disc florets | corollas yellow; anthers yellow. |
corollas yellow; anthers yellow. |
Phyllaries | 10–22, usually broadly lanceolate, rarely narrowly lanceolate or oblanceolate. |
12–18, narrowly ovate. |
Heads | 1 or 3–7. |
3–20. |
Cypselae | grayish brown to black, 4–8 mm, mostly stipitate-glandular, sparsely hirsutulous (hairs white to brownish, simple or bifid); pappi tawny, bristles plumose (with deep, amberlike deposits). |
dark gray to dark brown, 5–7 mm, glabrous or sparsely stipitate-glandular; pappi white, bristles barbellate. |
2n | = 38, 57, 76, 95, 114, 133, 152. |
= 38. |
Arnica mollis |
Arnica acaulis |
|
Phenology | Flowering Jun–Sep. | Flowering Apr–Jun. |
Habitat | Moist meadows and conifer forests, stream banks, late snow-melt areas, montane to subalpine | Sandy pine woods and clearings, often in damp soils, chiefly on Coastal Plain |
Elevation | 1000–4000 m (3300–13100 ft) | 0–300 m (0–1000 ft) |
Distribution |
AK; CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC; NT; YT
|
DC; DE; FL; GA; MD; NC; NJ; PA; SC; VA
|
Source | FNA vol. 21, p. 372. | FNA vol. 21, p. 368. |
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Arnica | Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Arnica |
Sibling taxa | ||
Synonyms | Doronicum acaule | |
Name authority | Hooker: Fl. Bor.-Amer. 1: 331. (1834) | (Walter) Britton: Prelim. Cat., 30. (1888) |
Web links |