Ranunculus acris
Ranunculus inamoenus
acrid buttercup, bouton d'or, meadow buttercup, renoncule âcre, tall buttercup, tall crowfoot
graceful buttercup, unlovely buttercup
never tuberous.
slender, 0.6-1.2 mm thick.
erect from short caudex or rhizome, never rooting nodally, hispid, strigose, or glabrous, base not bulbous.
erect, 5-33 cm, pilose or glabrous, each with 3-7 flowers.
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.
persistent, blades ovate, obovate or orbiculate, rarely reniform, undivided or innermost with 2 clefts or partings near apex, 1-3.7 × 1.1-3.5 cm, base acute to rounded, margins entire, apex rounded.
receptacle glabrous;
sepals spreading, 4-6(-9) × 2-5 mm, hispid;
petals 5, yellow, 8-11(-17) × 7-13 mm.
pedicels appressed-pubescent;
receptacle pilose or glabrous;
sepals 3-5 × 2-3 mm, abaxially pilose, hairs colorless;
petals 5, 4-9 × 2-5 mm;
nectary scale glabrous.
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.
cylindric, 7-17 × 5-8 mm;
achenes 1.5-2 × 1.3-1.8 mm, canescent or glabrous;
beak subulate, straight or hooked, 0.4-2 mm.
= 14.
Ranunculus acris
Ranunculus inamoenus
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.)
The Navaho-Ramah considered Ranunculus inamoenus to be an effective hunting medicine, used to protect hunters from their prey (D. E. Moerman 1986).
Varieties 2 (2 in the flora).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Sepals 3–5 mm; beaks of achenes 0.4–0.9 mm. | var. inamoenus |
1. Sepals 5–7 mm; beaks of achenes 1.4–2 mm. | var. subaffinis |
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