Cyperus diandrus

Illustrator: Yevonn Wilson-Ramsey

Copyright: Flora of North America Association

Herbs, annual, cespitose, with fibrous roots. Culms trigonous, 4–25(–35) cm, glabrous. Leaves flat, 5–20 cm × 1.5–3 mm. Inflorescences: heads ± digitate, 12–22 mm diam.; rays 3–6, 1–6 cm; bracts 1–4, ± horizontal, flat, 1.5–15 cm × 1.5–3 mm. Spikelets 6–12, oblong-lanceoloid, compressed, 5–10 × 2.8–3.2 mm; floral scales 8–28, closely imbricate, stramineous to light brown or clear (marginal band bright red, spikelet thus appearing dark margined), laterally ribless, oblong to ovate, 2.5–3 × 1.6–1.9 mm. Flowers: stamens 2(–3); anthers 0.3 mm, connective apex reddish, subulate, 0.1–0.2 mm; styles 0.3–0.5 mm; stigmas 2.2–3.1 mm. Achenes brown, network of ridges forming isodiametric or square cells, sessile or stipitate, obovoid to ovoid, 1–1.2 × 0.5–0.6 mm, stipe, if present, 0.1 mm, apex obtuse, apiculate, surfaces minutely punctate.

Phenology: Fruiting summer.
Habitat: Emergent shorelines, in sandy, peaty, or slightly brackish areas (though seldom where disturbed)
Elevation: 0–600 m

Distribution

• Generated Map
• Legacy Map

N.B., N.S., Ont., Que., Conn., Del., Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., Mo., Nebr., N.H., N.J., N.Y., Pa., R.I., Vt., Va.

Discussion

Selected References

None.

Lower Taxa

None.