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Photo is of parent taxon

western buttercup

Photo is of parent taxon

Nelson's buttercup

Stems

erect to reclining, 1-3(-4) mm thick, hirsute or sometimes glabrous.

erect or spreading, 4-8 mm thick, hirsute.

Basal leaf blades

3-parted or -foliolate, ultimate segments oblong or elliptic to lanceolate or oblanceolate, margins dentate or dentate-lobulate.

3-parted, rarely 3-foliolate, ultimate segments elliptic, margins dentate.

Flowers

sepals 5, 4-7 mm;

petals 5-6, 5-10 × 3-6 mm.

sepals 5, 4-9 mm;

petals 5-6, 7-15 × 4-11 mm.

Achenes

2.6-3.6(-4) × 1.8-3(-3.2) mm, glabrous or hispid;

beak lanceolate, curved, (0.6-)1-1.4 mm.

3-4 × 2.2-2.8 mm, glabrous;

beak lanceolate, curved, 1.8-2.4 mm.

Ranunculus occidentalis var. occidentalis

Ranunculus occidentalis var. nelsonii

Phenology Flowering late winter–spring (Mar–Jun). Flowering spring (May–Jun).
Habitat Grassy slopes of meadows or open woodlands Moist places near coast
Elevation 0-1500 m (0-4900 ft) 0 m (0 ft)
Distribution
from FNA
CA; NV; OR; WA; BC
[BONAP county map]
from FNA
AK
[BONAP county map]
Discussion

L. D. Benson (1948) divided Ranunculus occidentalis var. occidentalis into three varieties. The name R. occidentalis var. occidentalis was applied only to plants from Oregon northward, in which leaves are rarely compound and never have lanceolate ultimate segments, and achenes are always glabrous and have beaks over 1 mm. California plants were treated as R. occidentalis var. rattanii (plants with small [5-8 mm] petals from the Coast Ranges) and R. occidentalis var. eisenii (plants with larger petals from the foothills surrounding the Central Valley). Most of those plants from California, however, cannot be distinguished from more northern plants, and forms with small petals are found throughout the range of the variety.

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

Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Ranunculus > Ranunculus occidentalis Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Ranunculus > Ranunculus occidentalis
Sibling taxa
R. occidentalis var. brevistylis, R. occidentalis var. dissectus, R. occidentalis var. hexasepalus, R. occidentalis var. howellii, R. occidentalis var. nelsonii, R. occidentalis var. ultramontanus
R. occidentalis var. brevistylis, R. occidentalis var. dissectus, R. occidentalis var. hexasepalus, R. occidentalis var. howellii, R. occidentalis var. occidentalis, R. occidentalis var. ultramontanus
Synonyms R. occidentalis var. eisenii, R. occidentalis var. rattanii R. recurvatus var. (ß), R. occidentalis subsp. nelsonii
Name authority unknown (de Candolle) L. D. Benson: Bull. Torrey Bot. Club 68: 166. (1941)
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