Cyperus drummondii |
Cyperus cuspidatus |
|
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Drummond's sedge |
coastal plain flatsedge |
|
Habit | Herbs, perennial, cespitose; rhizomes 0.5–2 cm, often absent. | Herbs, annual, cespitose. |
Culms | trigonous, 35–170 cm × 2–4.7 mm, scabrid on angles. |
1–6(–25), trigonous to roundly trigonous, (0.5–)2–5(–9) cm × 0.2–0.4–(0.6) mm, glabrous. |
Leaves | 4–12, with readily visible cross ribs especially on abaxial surface, flat to V-shaped, 25–100 cm × 2.4–11 mm. |
1–6, V-shaped, 1–6 cm × 0.3–1 mm. |
Inflorescences | heads digitate, globose, 1–1.7 cm diam.; rays 3–5, 1–7 cm; 2d order rays absent; bracts 3–5, horizontal to ascending at 30°, with prominent cross ribs, V-shaped, (4–)11–35(–48) cm × 1–6.7 mm (longest 1/2 as long as culm); 2d order bracts absent. |
heads digitate, loosely ovoid, 3–18 × 3–26 mm; rays (0–)1–6(–8), 2.5–20(–30) mm; bracts 2–3(–5), horizontal to ascending at 45(–60)°, V-shaped, 2–60 × 0.3–1.2 mm. |
Spikelets | 10–40, oblong to linear-lanceoloid, 5–1.8 × 1.5–2.2 mm; floral scales 18–42, pale grayish green, turning brownish, proximally greenish or brownish, 2-keeled, weakly to distinctly 1-ribbed, proximal 1/2 2-ribbed, ovate, 1.4–1.6 × 0.9–1.4 mm, acute (sometimes mucronulate), apically glabrous, occasionally scabridulous. |
(3–)10–20(–30), greenish to reddish brown, narrowly ellipsoid to oblong, 3–11 × (0.8–)1.2–1.5 mm; floral scales (3–)6–20(–28), laterally greenish to reddish brown, glossy, medially greenish to light reddish brown, strongly recurved, laterally ribless, medially strongly 3-ribbed, oblong-ovate, (0.8–)1–1.3 × 0.8–1(–1.2) mm, apex emarginate, cusp 0.6–1.2 mm. |
Flowers | stamens 1–2; anthers 0.8–1.2 mm; styles 0.8–1 mm; stigmas 0.6–0.8 mm. |
stamens 2 or 3; anthers oblong-ovoid, 0.1(–0.2) mm; styles (0.2–)0.4–0.6 mm; stigmas 0.3–0.5 mm. |
Achenes | brown, slightly stipitate, oblong-ellipsoid (2.4–3.9 times longer than wide), 1–1.2 × 0.3–0.5 mm, apical beak 0.1–0.5 mm, surfaces glabrous. |
brown, oblong-obovoid, (0.5–)0.6 × (0.3–)0.4 mm, base cuneate, apex blunt, surfaces coarsely papillose. |
Cyperus drummondii |
Cyperus cuspidatus |
|
Phenology | Fruiting late spring–summer. | Fruiting summer. |
Habitat | Wet, relatively undisturbed habitats, especially flatwoods, ponds, seepage slopes, coastal prairies | Damp, disturbed soils |
Elevation | 0–200 m (0–700 ft) | 0–300 m (0–1000 ft) |
Distribution |
AL; FL; GA; LA; MS; SC; TX; Central America; South America; West Indies |
AL; FL; GA; SC; Mexico; Central America; South America
|
Discussion | Cyperus drummondii has been treated as a synonym (G. C. Tucker 1994), or a variety (G. Kükenthal 1935–1936), or a subspecies of C. virens (M. F. Denton 1978b). Recent quantitative and field studies (J. R. Carter et al. 1999) provided compelling evidence that specific status is appropriate. Compared to Cyperus virens, C. drummondii is a taller species of less disturbed habitats and has narrower spikelets, ovate scales, and fewer inflorescence bracts. Cyperus virens and C. drummondii are readily distinguished from other Cyperus species in the United States by their sharply angled, scabrid culms and conspicuously septate leaf blades. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23. | FNA vol. 23, p. 158. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Pycnostachys |
Sibling taxa | ||
Synonyms | C. robustus, C. virens subsp. drummondii, C. virens var. drummondii, C. virens var. robustus | |
Name authority | Torrey & Hooker: Ann. Lyceum Nat. Hist. New York 3: 437, errata. (1836) | Kunth: in A. von Humboldt et al., Nov. Gen. Sp. 1: 204. (1816) |
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