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Ranunculus triternatus

Dalles Mountain buttercup, obscure buttercup

Ranunculus austro-oreganus

southern Oregon buttercup

Roots

cylindric, 2-3 mm thick.

never tuberous.

Stems

prostrate or ascending, 5-20 cm, glabrous, each with 1-6 flowers.

erect or ascending, never rooting nodally, crisped-pilose, base not bulbous.

Basal leaves

persistent, blades rhombic to deltate or reniform in outline, 3-4x-dissected, 1.1-3.4 × 2-3.1 cm, segments linear, base obtuse, margins crenate, apices of segments narrowly rounded.

Basal leaf blades

broadly rhombic to semicircular in outline, 3-parted, 2.8-4.3 × 3-5.5 cm, segments 3-lobed, ultimate segments lanceolate, margins entire or toothed, apex narrowly acute or acuminate.

Flowers

pedicels glabrous;

receptacle short-pubescent;

sepals 4-8 × 2-5 mm, abaxially glabrous or nearly so;

petals 5, 6-15 × 4-10 mm;

nectary scale glabrous.

receptacle glabrous;

sepals reflexed 1 mm above base, 4-6 × 1.5-3 mm, densely pilose;

petals 5, abaxially red, adaxially yellow, 10-12 × 4-6 mm.

Heads of achenes

depressed-globose, 4-6 × 5-8 mm;

achenes 1.8-2.2 × 1.2-1.8 mm, finely pubescent;

beak subulate, straight, 0.8-1.5 mm.

hemispheric, 4-7 × 7-10 mm;

achenes 3.4-4.2 × 2.8-3.2 mm, sometimes basally pilose, margin forming narrow rib 0.1-0.2 mm wide;

beak persistent, lance-subulate, straight or somewhat curved distally, 1.6-2.6 mm.

Ranunculus triternatus

Ranunculus austro-oreganus

Phenology Flowering spring (Apr–May). Flowering spring (May).
Habitat Grassland or sagebrush Grassy hillsides
Elevation 900-1700 m (3000-5600 ft) 500 m (1600 ft)
Distribution
from FNA
ID; NV; OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
OR
Discussion

Of conservation concern.

C. L. Hitchcock et al. (1955-1969, vol. 2) considered the name Ranunculus triternatus A. Gray to be an illegitemate homonym and used the illegitimate (superfluous) name R. reconditus A. Nelson & J. F. Macbride for this species. The name Ranunculus triternatus Poiret was not validly published (not accepted by Poiret) and does not invalidate R. triternatus A. Gray.

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

Of conservation concern.

Ranunculus austro-oreganus is doubtfully distinct from R. occidentalis var. howellii. L. D. Benson (1954) described the stem as bulbous-based and similar to that of R. bulbosus, but a differentiated base is not evident in material I have seen (some of which was cited by Benson).

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

Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Epirotes 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. 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. 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. 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, R. uncinatus
Synonyms R. glaberrimus var. reconditus
Name authority A. Gray: Proc. Amer. Acad. Arts 21: 370. (1886) L. D. Benson: Amer. Midl. Naturalist 52: 341. (1954)
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