Northern Prairie Wildlife Research Center
Western Wetland Flora
Field Office Guide to Plant Species
Ranunculus subrigidus W. B. Drew
- Family: Butter-cup (Ranunculaceae)
- Flowering: May-July
- Field Marks: This is an aquatic, white-flowered butter-cup with much divided submersed leaves and no floating leaves. Its flower stalks become curved by fruiting time.
- Habitat: In ponds, in slow streams.
- Habit: Perennial herb with submersed stems.
- Stems: Submersed, smooth, up to 2 feet long.
- Leaves: All leaves submersed, up to 2 inches long, much divided into thread-like segments, smooth.
- Flowers: Several in clusters, up to 3/4 inch across, each flower on a stalk up to 2 inches long.
- Sepals: 5, green, free from each other, up to 1/4 inch long.
- Petals: 5, white, free from each other, up to nearly 1/2 inch long.
- Stamens: 5-10.
- Pistils: Many, each with a superior ovary, smooth.
- Fruits: Achenes 30 or more in clusters at the tip of a curved stalk, each achene obovoid, up to 1/16 inch long, smooth, with a minute beak.
- Notes: The achenes are eaten by waterfowl.
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