Ranunculus canus
Ranunculus californicus
Hartweg's buttercup, Sacramento Valley buttercup
California buttercup, common buttercup
never tuberous.
never tuberous.
erect to decumbent, never rooting nodally, hirsute, pilose, or glabrous, base not bulbous.
erect to prostrate, never rooting nodally, hirsute, strigose, or glabrous, base not bulbous.
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.
blades broadly ovate or cordate in outline, 3-lobed or -parted to 3-foliolate, 1.8-5.8 × 2.3-7.6 cm, leaflets or segments undivided or 1-2x-lobed or -parted, ultimate segments linear to orbiculate, margins toothed, crenate, or entire, apex acute to rounded.
receptacle glabrous;
sepals reflexed 1-2 mm above base, 3-8 × 2-4 mm, hirsute;
petals 5-17, yellow, 6-12 × 3-6 mm.
receptacle glabrous or rarely hispid;
sepals reflexed 2-3 mm above base, 4-8 × 2-4 mm, pilose;
petals 9-17, yellow, (6-)7-14 × 2-6 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.
globose or hemispheric, 3-7 × 4-9 mm;
achenes 1.8-3.2 × 1.4-3.2 mm, glabrous, rarely hispid, margin forming narrow rib 0.1-0.2 mm wide;
beak persistent, lanceolate, curved, 0.2-0.8 mm.
Ranunculus canus
Ranunculus californicus
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.)
Varieties 2 (2 in the flora).
In addition to the range given, localized populations of Ranunculus californicus have been reported recently from a few islands in the vicinity of Victoria (British Columbia and Washington) (M. F. Denton 1978; T. C. Brayshaw 1989). Those populations are small and introgress freely with R. occidentalis wherever they come together. Denton referred her specimens to R. californicus var. cuneatus; Brayshaw reported both varieties from the same small populations, but his data are consistent with populations of R. californicus var. cuneatus that are introgressing extensively with R. occidentalis. Although both Denton and Brayshaw treat R. californicus as a native species in that region, several reasons support the belief that it is introduced there. No reports of R. californicus in the area occur prior to 1978, although the area is quite well collected (especially Victoria, B. C. and the San Juan Islands, Washington); a long history of extensive marine trade between Victoria and San Francisco has resulted in the introduction of a number of other California species to the area; and for scattered small populations of R. californicus to have persisted for long periods in the face of free introgression from R. occidentalis seems unlikely. Given the small population size and the introgression from R. occidentalis, it is questionable whether R. californicus can persist in the area.
(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 |
1. Stems erect to decumbent, hirsute or glabrous; ultimate segments of basal leaf blades acute to rounded-acute at apex. | var. californicus |
1. Stems prostrate, strigose; ultimate segments of basal leaf blades rounded to obtuse at apex. | var. cuneatus |
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
