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
10. Ranunculus sceleratus L. -- Cursed crowfoot
Weedy annual, glabrous or rarely hirsute, 1-5 dm tall or the stem to 10 dm long
when submersed. Stems erect, inflated and hollow, sparsely to profusely
branched, especially above. Leaves basal and cauline, the basal leaves
often longer-petioled and less deeply dissected than the cauline ones, often
floating when submersed; blades deeply 3-parted or divided, broadly truncate
or cordate at the base, distally rounded, 1-6 cm long, 3-8 cm wide, the primary
lobes or divisions lobed or divided, the ultimate lobes obtuse to rounded; petioles
2-15 cm long or much longer when submersed; stipular bases dilated, membranous,
5-12 mm long. Flowers numerous; sepals 5, yellowish-green, reflexed,
2-3 mm long, deciduous with the petals, glabrous; petals 5, light yellow,
fading white, 3-5 mm long; stamens usually 10-25; receptacle 1.5-3
mm long in flower, 3-10 mm long in fruit. Achenes 40-300 in a cylindric-ovoid
or rarely globose head 4-11 mm long, 3.5-7 mm thick; achene body obovoid, 0.8-1.2
mm long, glabrous, obscurely keeled on the margins, somewhat corky-thickened
around the edges; beak minute and blunt. Jun--Sep. Shores, stream banks, mud
flats, wet meadows, ditches, marshes and other wet places; very common; (Circumboreal,
in N.Amer. s to FL, AR, LA, TX, NM and CA).
Two varieties of R. sceleratus are found in the northern Great Plains.
R. sceleratus var. multifidus Nutt. is prevalent throughout.
It has the achenes smooth in the central area of each face except for
pinprick depressions surrounding the smooth area. The var. sceleratus
has achenes cross-corrugated or reticulate in the central area of each
face. The latter is more common in the e part.
Previous Species -- Ranunculus pensylvanicus
L. f. -- Bristly crowfoot
Return to Family -- Ranunculaceae -
The Buttercup Family
Next Species -- Ranunculus subrigidus W.B.
Drew -- White water-crowfoot