Northern Prairie Wildlife Research Center
Aquatic and Wetland Vascular Plants of the Northern Great Plains
9. Ranunculaceae, the Buttercup Family
4. Ranunculus L. -- Buttercup, crowfoot
9. Ranunculus pensylvanicus L. f. -- Bristly crowfoot
Hirsute annual or shortlived perennial 4-10 dm tall, resembling the preceding.
Stems hollow, erect, branching and flowering like R. macounii.
Basal leaves often withering early, larger and longer-petioled than the
cauline leaves; blades of basal and cauline leaves pinnately compound, 4-12
cm long, 4-15 cm wide, appressed-hairy to rarely glabrous, the leaflets lobed
and coarsely toothed, tapered to the slender bases, the terminal one 3-parted,
the lateral ones 2- or 3-parted; stipular bases 1-4 cm long. Sepals 5,
yellowish, reflexed, (3)4-5 mm long, deciduous, sparsely hirsute; petals
5, pale yellow, fading whitish, distinctly shorter than the sepals, (1.5)2-3
mm long; stamens 15-20, anthers less than 1 mm long; receptacle
2 mm long in flower, 5-13 mm long in fruit, short-pubescent. Achenes
60-80 in an ovoid-cylindric to cylindric head 10-15 mm long, 6-9 mm thick; achene
body flattened, obovate, (1.5)2-2.5 mm long, smooth and glabrous, keeled on
the margin; beak stout, deltoid, 0.6-0.9 mm long. Jun--Aug. Occurring in the
same habitats as R. macounii but intolerant of brackish conditions; common
in the e part, less frequent w; (Newf. to AK, s to NJ, PA, OH, n IN, n IL, n
IA, NE, CO, AZ and OR; also e Asia).
Previous Species -- Ranunculus macounii Britt.
-- Macoun's buttercup
Return to Family -- Ranunculaceae -
The Buttercup Family
Next Species -- Ranunculus sceleratus L. --