Ranunculus adoneus
Ranunculus canus
alpine buttercup
Hartweg's buttercup, Sacramento Valley buttercup
slender, 0.8-1.4 mm thick.
never tuberous.
erect from large caudices, 9-25 cm, glabrous, each with 1-3 flowers.
erect to decumbent, never rooting nodally, hirsute, pilose, or glabrous, base not bulbous.
persistent, blades circular to reniform in outline, 2-3x-dissected into linear segments, 0.9-2.5 × 1.1-2.8 cm, base obtuse, margins entire, apices of segments narrowly rounded to acute.
blades ovate to narrowly ovate in outline, 3-parted or -foliolate, 3.3-9.5 ×3.5-9.4 cm, leaflets or segments 1-3x-lobed, ultimate segments ovate or oblong-ovate to lanceolate, margins toothed, apex acute or obtuse.
pedicels glabrous;
receptacle glabrous;
sepals 4-11 × 3-7 mm, abaxially sparsely pilose, hairs colorless;
petals 5-10, 8-15 × 8-19 mm;
nectary scale glabrous.
receptacle glabrous;
sepals reflexed 1-2 mm above base, 3-8 × 2-4 mm, hirsute;
petals 5-17, yellow, 6-12 × 3-6 mm.
ovoid, 6-12 × 5-9 mm;
achenes 1.8-2.4 × 1-1.4 mm, glabrous or nearly so;
beak subulate, straight, 1.2-1.7 mm.
hemispheric to globose, 6-9 × 7-10 mm;
achenes 3.4-4.4 × 2.4-3.6 mm, glabrous or rarely hispid, margin forming narrow rib 0.1-0.2 mm wide;
beak persistent, deltate or lance-deltate, curved, 0.2-1.2 mm.
n = 16.
Ranunculus adoneus
Ranunculus canus
Most collections of Ranunculus adoneus from Colorado, including the type specimen, tend to be small, with narrow leaf segments (only 0.5-1 mm wide) and large flowers. The more widespread form, with leaf segments 1-2 mm wide and more variable flowers, has been called R. adoneus var. alpinus. The leaf and flower characteristics are very poorly correlated, however, and specimens referable to var. alpinus vary greatly in stature and flower size, so the two forms scarcely merit formal recognition.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Varieties 2 (2 in the flora).
Ranunculus canus intergrades with R. occidentalis var. occidentalis and R. californicus, and some populations can be difficult to assign to species. The deltate or lance-deltate achene beak of R. canus, however, which is usually 0.8-1.2 mm wide at the base and less than 1.5 times as long as wide, contrasts with the narrower beaks of the other two species, which are usually less than 0.6 mm wide and at least twice as long as wide.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Petals 5–7; Sacramento Valley and adjacent foothills. | var. canus |
1. Petals 13–17; Transverse Ranges. | var. ludovicianus |
CalFlora
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
