Arnica discoidea

Bentham

Pl. Hartw., 319. 1849.

Common names: Rayless arnica
Endemic
Synonyms: Arnica alata Rydberg Arnica cordifolia var. eradiata A. Gray Arnica discoidea var. alata (Rydberg) Cronquist Arnica discoidea var. eradiata (A. Gray) Cronquist Arnica parviflora
Treatment appears in FNA Volume 21. Treatment on page 375. Mentioned on page 367.

Plants 15–60 cm. Stems mostly simple or distally branched. Leaves 3–7 pairs, sometimes crowded at stem-bases (basal leaves often persistent on sterile rosettes); petiolate (petioles narrow, 1.5–8 cm, often broadly winged on distal reduced leaves); blades usually ovate to broadly lanceolate, seldom subcordate, 2–12 × 1–7 cm, margins usually serrate to coarsely dentate or crenate, rarely subentire, faces glabrate to pilose, stipitate-glandular. Heads 3–10 (–30; erect). Involucres turbinate-campanulate. Phyllaries 8–15, ovatelanceolate to narrowly lanceolate. Ray-florets usually 0 (corollas of peripheral florets rarely dilated, resembling rays). Disc-florets 20–50; corollas yellow; anthers yellow. Cypselae dark gray, 6–8 mm, hirsute (hairs duplex) and stipitate-glandular; pappi white, bristles usually barbellate, sometimes subplumose. 2n = 38, 57, 76.


Phenology: Flowering May–Jul.
Habitat: Chaparral, oak and pine forests
Elevation: 100–1500 m

Distribution

V21-942-distribution-map.gif

Calif., Nev., Oreg., Wash.

Discussion

Selected References

None.

Lower Taxa

None.
... more about "Arnica discoidea"
76 +, 57 +  and 38 +
not tailed +, rounded +  and obtuse +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
corymbiform +  and cymiform +
indeterminate +  and determinate +
Steven J. Wolf +
Bentham +
decurrent +
compound +  and simple +
2 cm20 mm <br />0.02 m <br /> (12 cm120 mm <br />0.12 m <br />) +
subcordate;usually ovate;broadly lanceolate +
1 cm10 mm <br />0.01 m <br /> (7 cm70 mm <br />0.07 m <br />) +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
subplumose +  and barbellate +
connate +  and distinct +
Rayless arnica +
stipitate-glandular +  and hairy +
stipitate-glandular +  and hirsute +
obovoid-cylindric +, fusiform +  and conic +
fertile +  and bisexual +
fertile +  and bisexual +
Calif. +, Nev. +, Oreg. +  and Wash. +
100–1500 m +
glabrate +  and pilose +
scabrellous +
subentire;crenate;dentate +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
campanulate +  and cylindric +
Chaparral, oak and pine forests +
discoid +  and radiate +
in cymiform or corymbiform arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.6 cm6 mm <br />0.006 m <br /> (2 cm20 mm <br />0.02 m <br />) +
turbinate-campanulate +
cauline +  and basal +
3 (?) +  and 7 (?) +
deltate +
stipitate-glandular +
toothed +  and entire +
2-carpellate +
subplumose +  and barbellate +
persistent +
10 +  and 50 +
aristate +
Flowering May–Jul. +
8 +  and 15 +
Pl. Hartw., +
bearing subulate enations +, hairy +  and bristly +
pitted +  and smooth +
distinct +
4 +  and 20 +
exalbuminous +
branched +  and simple +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Arnica alata +, Arnica cordifolia var. eradiata +, Arnica discoidea var. alata +, Arnica discoidea var. eradiata +  and Arnica parviflora +
Arnica discoidea +
species +
campanulate +  and cylindric +
80 cm800 mm <br />0.8 m <br /> (300 cm3,000 mm <br />3 m <br />) +
1 cm10 mm <br />0.01 m <br /> (80 cm800 mm <br />0.8 m <br />) +
toothed +  and entire +
80 cm800 mm <br />0.8 m <br /> (300 cm3,000 mm <br />3 m <br />) +
5 cm50 mm <br />0.05 m <br /> (100 cm1,000 mm <br />1 m <br />) +
80 cm800 mm <br />0.8 m <br /> (300 cm3,000 mm <br />3 m <br />) +