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nodding arnica, Parry's arnica

alpine arnica, arctic arnica, narrow-leaf arnica

Habit Plants 15–50(–60) cm. Plants 5–40 cm.
Stems

simple or branched among heads.

usually simple, rarely branched.

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).

1–5 pairs, mostly cauline;

petiolate (petioles broadly to narrowly winged, shorter than blades);

blades broadly lanceolate to linear, 2–20 × 0.3–4 cm, margins entire or irregularly denticulate or dentate, apices acute or acuminate, faces glabrous or densely woolly-villous and stipitate-glandular.

Involucres

turbinate to narrowly campanulate.

hemispheric.

Ray florets

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

6–16;

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.

9–22, usually narrowly to broadly lanceolate, sometimes oblanceolate.

Heads

(1–)3–9(–14; often nodding in bud).

1–3(–5; erect).

Cypselae

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

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

brown, 3–8 mm, densely hirsute, rarely glandular;

pappi white, bristles barbellate.

2n

= 38, 57, 76.

Arnica parryi

Arnica angustifolia

Phenology Flowering May–Sep.
Habitat Open conifer forests to alpine meadows
Elevation 500–3800 m [1600–12500 ft]
Distribution
from FNA
CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; MT; AB; BC; MB; NF; NT; NU; ON; QC; SK; YT; Europe; Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 2 (2 in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Leaves linear to broadly lanceolate, faces glabrousor moderately villous
subsp. angustifolia
1. Leaves narrowly lanceolate, faces densely white-woolly-villous
subsp. tomentosa
Source FNA vol. 21, p. 373. FNA vol. 21, p. 369.
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. 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. parryi, A. rydbergii, A. sororia, A. spathulata, A. unalaschcensis, A. venosa, A. viscosa
Subordinate taxa
A. angustifolia subsp. angustifolia, A. angustifolia subsp. tomentosa
Synonyms A. angustifolia subsp. eradiata, A. parryi subsp. sonnei, A. parryi var. sonnei A. alpina subsp. angustifolia, A. alpina var. angustifolia
Name authority A. Gray: Amer. Naturalist 8: 213. (1874) Vahl: in G. C. Oeder et al., Fl. Dan. 9(26): 5, plate 1524. (1816)
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