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western buttercup

hook fruit buttercup, little buttercup, woodland buttercup

Roots

never tuberous.

never tuberous.

Stems

erect to reclining, not rooting nodally, hirsute or sometimes pilose or glabrous, base not bulbous.

erect, never rooting nodally, hispid or glabrous, base not bulbous.

Basal leaf blades

broadly ovate to semicircular or reniform in outline, 3-parted or -foliolate, 1.5-5.3 × 2.2-8 cm, segments usually again 1(-2)×-lobed, ultimate segments oblong or elliptic to lanceolate or oblanceolate, margins dentate (sometimes dentate-lobulate or entire), apex acute to rounded-obtuse.

cordate to reniform in outline, 3-parted or sometimes 3-foliolate, 1.8-5.6 × 2.8-8.3 cm, segments again lobed, ultimate segments elliptic to lanceolate, margins toothed or crenate-toothed, apex acute to rounded-obtuse.

Flowers

receptacle glabrous;

sepals reflexed 2-3 mm above base, 4-7(-9) × 2-4 mm, hirsute;

petals 5-14, yellow, 5-13 × 1.5-8 mm.

receptacle glabrous;

sepals reflexed or sometimes spreading, 2-3.5 × 1-2 mm, pubescent;

petals 5, yellow, 2-4(-6) × 1-2(-3) mm.

Heads of achenes

hemispheric, 3-7 × 5-9 mm;

achenes 2.6-3.6(-4.8) × 1.8-3(-3.2) mm, glabrous, rarely hispid, margin forming narrow rib 0.1-0.2 mm wide;

beak persistent, lanceolate to lance-subulate, straight or curved, 0.4-2.2 mm.

globose or hemispheric, 4-7 × 4-7 mm;

achenes 2-2.8 × 1.6-2 mm, glabrous or sparsely hispid, margin forming narrow rib 0.1-0.2 mm wide;

beak persistent, lanceolate, curved, hooked, 1.2-2.5 mm.

2n

= 28.

Ranunculus occidentalis

Ranunculus uncinatus

Phenology Flowering spring–summer (Apr–Aug).
Habitat Moist meadows or woods, often along streams
Elevation 0-3400 m (0-11200 ft)
Distribution
from FNA
AK; CA; NV; OR; WA; AB; BC; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 7

The seeds of Ranunculus occidentalis were eaten by some Californian Indians. D. E. Moerman (1986) identified this taxon as an Aleut poison: juice of the flowers could be slipped into food to poison the person who ate it.

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

Plants with hispid stems and achenes are often separated as Ranunculus uncinatus var. parviflorus; these two characters are poorly correlated, however, and sometimes vary between plants in a single collection. Ranunculus uncinatus was reported from northeastern Alberta and adjacent Northwest Territories by H. J. Scoggan (1978-1979, part 3). The specimens have hairy receptacles and straight, broad achene beaks; they apparently represent small individuals of R. macounii.

Some Native Americans used Ranunculus uncinatus as an antrirheumatic, a diaphoretic, a disinfectant, and an orthopedic aid, as well as in herbal steam baths intended to soothe sore muscles and rheumatism (D. E. Moerman 1986).

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

Key
1. Petals 8-14; Queen Charlotte Islands, B.C.
var. hexasepalus
1. Petals 5-6; widespread.
→ 2
2. Stem 4-8 mm thick; beak of achene 1.8-2.4 mm, curved; coastal Alaska.
var. nelsonii
2. Stem 1-3(-4) mm thick; beak of achene either 0.4-1.4 mm and curved, or 1.2-2.2 mm and straight; widespread.
→ 3
3. Beak of achene straight, 1.2-2.2 mm; Oregon and northernmost California.
→ 4
3. Beak of achene curved, 0.4-1.4 mm; widespread.
→ 5
4. Ultimate segments of leaves lanceolate to oblanceolate.
var. dissectus
4. Ultimate segments of leaves elliptic.
var. howellii
5. Petals 1.5-2.5 mm wide; beak of achene 0.4-1.2 mm; stems ± reclining; Sierra Nevada, above 1000m.
var. ultramontanus
5. Petals 3-8 mm wide; beak of achene (0.6-)1-1.4 mm; stems erect or reclining; widespread.
→ 6
6. Stems pilose or glabrous; Alaska to c British Columbia and Alberta.
var. brevistylis
6. Stems hirsute, sometimes glabrous; California to sw British Columbia.
var. occidentalis
Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Ranunculus Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Ranunculus
Sibling taxa
R. abortivus, R. acriformis, R. acris, R. adoneus, R. alismifolius, R. allegheniensis, R. allenii, R. ambigens, R. andersonii, R. aquatilis, R. arizonicus, R. arvensis, R. auricomus, R. austro-oreganus, R. bonariensis, R. bulbosus, R. californicus, R. canus, R. cardiophyllus, R. cooleyae, R. cymbalaria, R. eschscholtzii, R. fascicularis, R. fasciculatus, R. ficaria, R. flabellaris, R. flammula, R. gelidus, R. glaberrimus, R. glacialis, R. gmelinii, R. gormanii, R. harveyi, R. hebecarpus, R. hederaceus, R. hispidus, R. hydrocharoides, R. hyperboreus, R. hystriculus, R. inamoenus, R. jovis, R. kamtschaticus, R. lapponicus, R. laxicaulis, R. lobbii, R. macauleyi, R. macounii, R. macranthus, R. marginatus, R. micranthus, R. muricatus, R. nivalis, R. oresterus, R. orthorhynchus, R. pacificus, R. pallasii, R. parviflorus, R. pedatifidus, R. pensylvanicus, R. platensis, R. populago, R. pusillus, R. pygmaeus, R. ranunculinus, R. recurvatus, R. repens, R. rhomboideus, R. sabinei, R. sardous, R. sceleratus, R. sulphureus, R. testiculatus, R. trilobus, R. triternatus, R. turneri, R. uncinatus
R. abortivus, R. acriformis, R. acris, R. adoneus, R. alismifolius, R. allegheniensis, R. allenii, R. ambigens, R. andersonii, R. aquatilis, R. arizonicus, R. arvensis, R. auricomus, R. austro-oreganus, R. bonariensis, R. bulbosus, R. californicus, R. canus, R. cardiophyllus, R. cooleyae, R. cymbalaria, R. eschscholtzii, R. fascicularis, R. fasciculatus, R. ficaria, R. flabellaris, R. flammula, R. gelidus, R. glaberrimus, R. glacialis, R. gmelinii, R. gormanii, R. harveyi, R. hebecarpus, R. hederaceus, R. hispidus, R. hydrocharoides, R. hyperboreus, R. hystriculus, R. inamoenus, R. jovis, R. kamtschaticus, R. lapponicus, R. laxicaulis, R. lobbii, R. macauleyi, R. macounii, R. macranthus, R. marginatus, R. micranthus, R. muricatus, R. nivalis, R. occidentalis, R. oresterus, R. orthorhynchus, R. pacificus, R. pallasii, R. parviflorus, R. pedatifidus, R. pensylvanicus, R. platensis, R. populago, R. pusillus, R. pygmaeus, R. ranunculinus, R. recurvatus, R. repens, R. rhomboideus, R. sabinei, R. sardous, R. sceleratus, R. sulphureus, R. testiculatus, R. trilobus, R. triternatus, R. turneri
Subordinate taxa
R. occidentalis var. brevistylis, R. occidentalis var. dissectus, R. occidentalis var. hexasepalus, R. occidentalis var. howellii, R. occidentalis var. nelsonii, R. occidentalis var. occidentalis, R. occidentalis var. ultramontanus
Synonyms R. bongardii, R. bongardii var. tenellus, R. uncinatus var. earlei, R. uncinatus var. parviflorus
Name authority Nuttall: in J. Torrey & A. Gray, Fl. N. Amer. 1: 22. (1838) D. Don: in G. Don, Gen. Hist. 1: 35. (1831)
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