Ranunculus canus
Ranunculus acris
Hartweg's buttercup, Sacramento Valley buttercup
acrid buttercup, bouton d'or, meadow buttercup, renoncule âcre, tall buttercup, tall crowfoot
never tuberous.
never tuberous.
erect to decumbent, never rooting nodally, hirsute, pilose, or glabrous, base not bulbous.
erect from short caudex or rhizome, never rooting nodally, hispid, 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 pentagonal in outline, deeply 3-5-parted, 1.8-5.2 × 2.7-9.8 cm, segments 1-2x-lobed or -parted, ultimate segments narrowly elliptic or oblong to lanceolate, margins toothed or lobulate, 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;
sepals spreading, 4-6(-9) × 2-5 mm, hispid;
petals 5, yellow, 8-11(-17) × 7-13 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, 5-7(-10) mm wide;
achenes 2-3 × 1.8-2.4 mm, glabrous, margin forming narrow rib 0.1-0.2 mm wide;
beak persistent, deltate, usually with tip short or long, straight or curved, subulate, 0.2-1 mm.
= 14.
Ranunculus canus
Ranunculus acris
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.)
Ranunculus acris is variable in form and division of leaves, size of achene beak, and form of indument on the proximal stem. Most North American plants are weedy and have poorly differentiated caudices; these forms probably were introduced from Eurasia. Rhizomatous plants with large flowers (parenthetic measurements above) found in the Aleutian Islands of Alaska and in Greenland are probably native. Aleutian populations of this form have been called R. acris var. frigidus Regel or R. grandis Honda var. austrokurilensis (Tatewaki) H. Hara. Both names were originally applied to Asiatic plants, and their applicability to American specimens is open to question.
Some Native American tribes used Ranunculus acris as an analgesic, a dermatological or oral aid, an antidiarrheal, antihermorrhagic, and a sedative (D. E. Moerman 1986).
(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 |
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
