Northern Prairie Wildlife Research Center
BUTTERCUP FAMILY (Ranunculaceae)
IND. STATUS: OBL
FIELD CHARACTERISTICS: An aquatic herb, either floating or submerged. The stem is hollow, smooth and elongate. Leaves are highly variable. The submerged leaves are flattened and dissected into many segments 1-2 mm. wide. The emergent leaves, if present, are 3-parted. Flowers are on emergent, long, thick stalks. Petals number 5 and are (6.5)7-14(16) mm. long and golden yellow. Nutlets are 1.7-2.2 mm. long and are arranged in a densely-packed, fruiting head. The nutlets have a corky margin at maturity. In flower from April to June.
ECOLOGICAL NOTES: Yellow water crowfoot is found in shallow, open water and in marshes; sometimes stranded on muddy shores. A similar species with white flowers is white water crowfoot (R. longirostris).
SOURCE: Fernald (1970); Gleason and Cronquist (1991); and Voss (1985).