Cyperus retrofractus
in J. Carey, Carices North. U.S., 519. 1847.
Herbs, perennial, cespitose. Culms with cormlike bases, sharply trigonous, 25–90 cm, glabrous proximally, minutely scabridulous distally. Leaves V-shaped, 14–40 cm × 3.5–8 mm, (pubescent on adaxial side of midrib). Inflorescences: spikes loose, obtrulloid to obdeltoid (broadest near apex, nearly as long as wide), 20–28(–34) × (12–)15–30 mm; rays 4–13, (1–)4–24 cm (longest ray shorter than bracts), glabrous; bracts 3–12, ascending at 30–45°, flat, 3–25 cm × 3–7 mm; rachilla persistent, wings 0.4–0.6 mm wide, covering 3/4 of mature achene. Spikelets 30–50, proximal one reflexed, distal ones divaricate, linear-lanceoloid, ± terete, (6.5–) 8–10(–17) × 0.5–0.7 mm; floral scales persistent, 3–6(–8), appressed, stramineous (suffused with reddish purple), 4–5-ribbed laterally, ovate-lanceolate, (4–)4.4–4.9(–5.4) × 1.3–1.5 mm; terminal scale not spinose, apex straight, excurved mucronate, or cuspidate. Flowers: anthers 0.7–1.2 mm; styles 1.5–2 mm; stigmas 2–2.5 mm. Achenes brown to brownish black, narrowly oblong, (2.2–)2.5–3 × 0.6–0.7 mm, base cuneate, apex obtuse, apiculate, surfaces puncticulate.
Phenology: Fruiting summer.
Habitat: Roadsides, pastures, disturbed sites in sandy or clayey soils
Elevation: 0–300 m
Distribution
![V23 307-distribution-map.jpg](/w/images/2/22/V23_307-distribution-map.jpg)
Ala., Ark., Del., D.C., Ga., Ky., Mo., N.J., N.C., Ohio, Pa., S.C., Tenn., Va.
Discussion
For information concerning nomenclature of Cyperus retrofractus, see J. R. Carter and C. E. Jarvis (1986).
Selected References
None.