Northern Prairie Wildlife Research Center
Yellow Flatsedge (Cyperus flavescens)
- Family: Sedge (Cyperaceae)
- Flowering: July-October.
- Field Marks: This species is distinguished by its straw-colored scales, its 2 styles, and its black achenes.
- Habitat: Moist, sandy soil along rivers and streams.
- Habit: Annual herb with fibrous roots.
- Stems: Erect, slender, smooth, usually longer than the leaves, up to 1 foot tall.
- Leaves: Elongated, narrow, smooth, up to 1/10 inch broad.
- Flowers: Borne in spikelets, each flower subtended by a scale; spikelets several in radiating clusters; some clusters on stalks, others sessile; each spikelet straw-colored, flat, up to 1 inch long, about 1/10 inch broad.
- Scales: Ovate, obtuse but with a short mucro, straw-colored, smooth, up to 1/8 inch long.
- Sepals: 0.
- Petals: 0.
- Stamens: 3.
- Pistils: Stigmas 2-cleft; ovary superior.
- Fruits: Achenes obovoid, flat, black, shiny, about 1/20 inch long.
- Notes: The achenes are eaten by waterfowl.
Previous Species -- Rusty Flatsedge (Cyperus ferruginescens)
Return to Species List -- Group 3
Next Species -- Fragrant Flatsedge (Cyperus odoratus)