Cyperus articulatus

Illustrator: Yevonn Wilson-Ramsey

Copyright: Flora of North America Association

Herbs perennial; rhizomes to 200 cm. Culms to 25 cm apart, 1(–3) together, terete (scarcely compressed in drying), occasionally trigonous for apical 1/3, 40–140(–200) cm, 4–12 mm thick at base, (1.2–)1.5–2.5 mm thick at apex (with conspicuous transverse septa ca. 3 cm apart basally, to 3–5 mm apart apically), glabrous or infrequently scabrid on angles apically; sheaths at base of culm, 2–3, (5–)10–25 cm, loose, papery. Leaves usually bladeless, blades when present, cross ribs prominent, especially adaxially, (1–)10–20(–40) cm × 4–6(–9) mm. Inflorescences: spikes 1(–5), broadly ovoid to ± umbellate, 15–45 × 10–30 mm; rays 5–7(–10), 0.3–8(–12) cm; 2d order rays occasionally present, 5–20 mm; bracts 2(–4), erect, longest appearing to be continuation of culm, deltate to lance-linear, 0.2–2(–9) cm × 1.5–4.5 mm; rachilla persistent, wings translucent, whitish, or stramineous, 0.4 mm wide. Spikelets (1–)5–10, linear, compressed, 10–35(–45) × 1.1–2 mm; floral scales deciduous, 15–45, spreading or appressed, laterally light brown, medially green to brown, laterally 1–2-ribbed, medially 3-ribbed, oblong-elliptic to ovate, 2.9–3.7 × 1.1–1.6(–1.8) mm, apex acute. Flowers: anthers 1.7–2.4 mm; styles 1.2–3.6 mm; stigmas 1.7–6 mm. Achenes brown, stipitate, obovoid-ellipsoid, 1.2–1.6 × 0.4–0.6 mm, stipe 0.1 mm, apex markedly apiculate, surfaces puncticulate.

Phenology: Fruiting summer.
Habitat: Marshes, shallow water, ditches
Elevation: 0–100 m

Distribution

• Generated Map
• Legacy Map

Ala., Fla., Ga., La., Miss., S.C., Tex., Mexico, Central America, South America, Asia, Africa.

Discussion

In habit, Cyperus articulatus is reminscent of larger plants of Juncus or Schoenoplectus and is the only North American Cyperus with such a reedlike appearance.

Selected References

None.

Lower Taxa

None.