Cyperus diandrus
Cat. Pl. New York, 90. 1819.
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
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
"shortened" is not a number.