Northern Prairie Wildlife Research Center
Northeast Wetland Flora
Field Office Guide to Plant Species
Cyperus polystachyos Rottb.
- Family: Sedge (Cyperaceae)
- Flowering: July-October
- Field Marks: This annual or sometimes perennial flatsedge is distinguished by its lenticular,
oblongoid achenes, 2-cleft style, more or less rounded scales, and linear spikelets only 1/12-1/10 inch wide.
- Habitat: Wet soil, shores, wet pine woods.
- Habit: Annual or perennial herb with fibrous roots.
- Stems: Sprawling and matted to upright, smooth, up to 1 1/2 feet tall.
- Leaves: Elongated, smooth, 1/8-1/6 inch wide, shorter than the stems.
- Flowers: Borne in spikelets, the spikelets arranged in an umbel subtended by 1-4 leaf-like
bracts; spikelets flattened, several-flowered, yellowish to rusty, linear, up to 1 inch long,
1/12-1/10 inch wide; scales narrowly ovate to elliptic, 1/12-1/10 inch long, more or less rounded
at the tip.
- Sepals: 0.
- Petals: 0.
- Stamens: 2.
- Pistils: Ovary superior; styles deeply 2-cleft.
- Fruits: Achenes lenticular, oblongoid, pale brown, only about 1/24 inch long.
- Notes: The minute seeds are eaten by waterfowl. In our range, all the individuals of this
species are considered to be of the var. texensis.
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