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nodding arnica, Parry's arnica

cordilleran arnica, cordilleran leopardbane, hairy arnica

Habit Plants 15–50(–60) cm. Plants 15–70 cm.
Stems

simple or branched among heads.

(forming clumps) simple or branched among heads.

Leaves

(2–)3–4 pairs, basal and cauline (basal usually withered by flowering, petiolate or subsessile, blades ovate or nearly round to oblong-ovate, much smaller than cauline; sterile rosettes often present, proximal cauline often crowded toward stems bases);

petiolate;

blades broadly to narrowly lanceolate, oblong-ovate, ovate-lanceolate, or round, 4–22 × 1–6 cm, (bases obtuse or cuneate to truncate) margins usually entire, sometimes sparsely denticulate, faces scantily to moderately pilose (hairs white), adaxial sparsely stipitate-glandular (distal cauline leaves sessile, extremely reduced, nearly linear to narrowly elliptic-lanceolate).

(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).

Involucres

turbinate to narrowly campanulate.

hemispheric to campanulate.

Ray florets

usually 0 (sometimes peripheral florets pistillate; corollas yellow, laminae rudimentary).

10–22;

corollas yellow.

Disc florets

20–50;

corollas yellow (1 or more lobes sometimes expanded, giving appearance of laminae);

anthers yellow.

corollas yellow;

anthers yellow.

Phyllaries

8–20, linear to narrowly lanceolate.

10–22, usually broadly lanceolate, rarely narrowly lanceolate or oblanceolate.

Heads

(1–)3–9(–14; often nodding in bud).

1 or 3–7.

Cypselae

brown to black, 4–7 mm, glabrous or sparsely stipitate-glandular to densely hirsute;

pappi usually stramineous, rarely tawny, bristles barbellate to ± subplumose.

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).

2n

= 38, 57, 76.

= 38, 57, 76, 95, 114, 133, 152.

Arnica parryi

Arnica mollis

Phenology Flowering May–Sep. Flowering Jun–Sep.
Habitat Open conifer forests to alpine meadows Moist meadows and conifer forests, stream banks, late snow-melt areas, montane to subalpine
Elevation 500–3800 m [1600–12500 ft] 1000–4000 m [3300–13100 ft]
Distribution
from FNA
CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC; NT; YT
[WildflowerSearch map]
[BONAP county map]
Source FNA vol. 21, p. 373. FNA vol. 21, p. 372.
Parent taxa Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Arnica Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Arnica
Sibling taxa
A. acaulis, A. angustifolia, A. cernua, A. chamissonis, A. cordifolia, A. dealbata, A. discoidea, A. fulgens, A. gracilis, A. griscomii, A. lanceolata, A. latifolia, A. lessingii, A. lonchophylla, A. longifolia, A. louiseana, A. mollis, A. nevadensis, A. ovata, A. rydbergii, A. sororia, A. spathulata, A. unalaschcensis, A. venosa, A. viscosa
A. acaulis, A. angustifolia, A. cernua, A. chamissonis, A. cordifolia, A. dealbata, A. discoidea, A. fulgens, A. gracilis, A. griscomii, A. lanceolata, A. latifolia, A. lessingii, A. lonchophylla, A. longifolia, A. louiseana, A. nevadensis, A. ovata, A. parryi, A. rydbergii, A. sororia, A. spathulata, A. unalaschcensis, A. venosa, A. viscosa
Synonyms A. angustifolia subsp. eradiata, A. parryi subsp. sonnei, A. parryi var. sonnei
Name authority A. Gray: Amer. Naturalist 8: 213. (1874) Hooker: Fl. Bor.-Amer. 1: 331. (1834)
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