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green flatsedge

Drummond's sedge

Habit Herbs, perennial, cespitose; rhizomes 0.5–2 cm, often absent. Herbs, perennial, cespitose; rhizomes 0.5–2 cm, often absent.
Culms

trigonous, (20–)60–70(–100) cm × 2.4–6.9 mm, scabrid on angles.

trigonous, 35–170 cm × 2–4.7 mm, scabrid on angles.

Leaves

4–12, flat to V-shaped, with readily visible cross ribs especially on abaxial surface, 20–50 cm × 3–14 mm.

4–12, with readily visible cross ribs especially on abaxial surface, flat to V-shaped, 25–100 cm × 2.4–11 mm.

Inflorescences

heads digitate to hemispheric, 1–3.5 cm diam.;

rays 6–12, 1–9(–14) cm; 2d order rays often present, (0.5–)1–3 cm; 3d order rays occasionally present, 5–12 mm;

bracts 4–8, horizontal to ascending at 30°, with prominent cross ribs,V-shaped, (1.5–)3–50(–75) cm × 0.5–13 mm; 2d order bracts 3–10 × 1–2 mm.

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.

Spikelets

10–40(–50), oblong to linear-lanceoloid, 5–18 × 2–3.2 mm;

floral scales 10–40, pale grayish brown, or greenish, proximally greenish or brownish, oblanceolate, 2-keeled, weakly to distinctly 1-ribbed, proximal half 2-ribbed, (1.3–)1.5–2(–2.4) × 0.9–1.4 mm, apex acute (sometimes mucronulate), apically glabrous, occasionally scabridulous.

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.

Flowers

stamens 1–2;

anthers 0.8–1.4 mm;

styles 0.8–1 mm;

stigmas 0.6–0.8 mm.

stamens 1–2;

anthers 0.8–1.2 mm;

styles 0.8–1 mm;

stigmas 0.6–0.8 mm.

Achenes

brown, slightly to distinctly stipitate, ellipsoid (2.7–4.1 times as long as wide), (0.9–)1.2–1.5 × 0.3–0.4 mm, apical beak 0.1–0.5 mm, surfaces glabrous.

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.

Cyperus virens

Cyperus drummondii

Phenology Fruiting spring–fall. Fruiting late spring–summer.
Habitat Wet pastures, marshes, roadside ditches Wet, relatively undisturbed habitats, especially flatwoods, ponds, seepage slopes, coastal prairies
Elevation 0–200 m (0–700 ft)
Distribution
from FNA
AL; FL; GA; LA; MS; NC; SC; TX; Mexico; Central America; South America
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; FL; GA; LA; MS; SC; TX; Central America; South America; West Indies
[BONAP county map]
Discussion

Cyperus virens was found as waif in California in the 1800s (M. F. Denton 1978b; G. C. Tucker 1993b).

Cyperus virens is readily distinguished from other species of subg. Pycnostachys by its trigonous culms, scabrid angles, and leaves and inflorescence bracts conspicuously septate by numerous cross ribs between the main ribs.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

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, p. 153. FNA vol. 23.
Parent taxa Cyperaceae > Cyperus > subg. Pycnostachys Cyperaceae > Cyperus > subg. Pycnostachys
Sibling taxa
C. acuminatus, C. aggregatus, C. alopecuroides, C. amabilis, C. articulatus, C. bipartitus, C. cephalanthus, C. compressus, C. croceus, C. cuspidatus, C. dentatus, C. dentoniae, C. diandrus, C. difformis, C. digitatus, C. dipsaceus, C. distans, C. distinctus, C. drummondii, C. echinatus, C. elegans, C. entrerianus, C. eragrostis, C. erythrorhizos, C. esculentus, C. fendlerianus, C. filicinus, C. filiculmis, C. filiformis, C. flavescens, C. flavicomus, C. floribundus, C. fugax, C. fuligineus, C. fuscus, C. giganteus, C. gracilis, C. granitophilus, C. grayi, C. grayoides, C. haspan, C. hermaphroditus, C. houghtonii, C. hypopitys, C. hystricinus, C. involucratus, C. iria, C. laevigatus, C. lancastriensis, C. lanceolatus, C. lecontei, C. lentiginosus, C. ligularis, C. lupulinus, C. manimae, C. microiria, C. mutisii, C. niger, C. ochraceus, C. odoratus, C. onerosus, C. ovatus, C. owanii, C. oxylepis, C. pallidicolor, C. papyrus, C. parishii, C. pilosus, C. planifolius, C. plukenetii, C. polystachyos, C. prolifer, C. prolixus, C. pseudothyrsiflorus, C. pseudovegetus, C. pumilus, C. reflexus, C. refractus, C. retroflexus, C. retrofractus, C. retrorsus, C. rotundus, C. sanguinolentus, C. schweinitzii, C. serotinus, C. seslerioides, C. setigerus, C. spectabilis, C. sphacelatus, C. sphaerolepis, C. squarrosus, C. strigosus, C. surinamensis, C. tetragonus, C. thyrsiflorus
C. acuminatus, C. aggregatus, C. alopecuroides, C. amabilis, C. articulatus, C. bipartitus, C. cephalanthus, C. compressus, C. croceus, C. cuspidatus, C. dentatus, C. dentoniae, C. diandrus, C. difformis, C. digitatus, C. dipsaceus, C. distans, C. distinctus, C. echinatus, C. elegans, C. entrerianus, C. eragrostis, C. erythrorhizos, C. esculentus, C. fendlerianus, C. filicinus, C. filiculmis, C. filiformis, C. flavescens, C. flavicomus, C. floribundus, C. fugax, C. fuligineus, C. fuscus, C. giganteus, C. gracilis, C. granitophilus, C. grayi, C. grayoides, C. haspan, C. hermaphroditus, C. houghtonii, C. hypopitys, C. hystricinus, C. involucratus, C. iria, C. laevigatus, C. lancastriensis, C. lanceolatus, C. lecontei, C. lentiginosus, C. ligularis, C. lupulinus, C. manimae, C. microiria, C. mutisii, C. niger, C. ochraceus, C. odoratus, C. onerosus, C. ovatus, C. owanii, C. oxylepis, C. pallidicolor, C. papyrus, C. parishii, C. pilosus, C. planifolius, C. plukenetii, C. polystachyos, C. prolifer, C. prolixus, C. pseudothyrsiflorus, C. pseudovegetus, C. pumilus, C. reflexus, C. refractus, C. retroflexus, C. retrofractus, C. retrorsus, C. rotundus, C. sanguinolentus, C. schweinitzii, C. serotinus, C. seslerioides, C. setigerus, C. spectabilis, C. sphacelatus, C. sphaerolepis, C. squarrosus, C. strigosus, C. surinamensis, C. tetragonus, C. thyrsiflorus, C. virens
Synonyms C. robustus, C. virens subsp. drummondii, C. virens var. drummondii, C. virens var. robustus
Name authority Michaux: Fl. Bor.-Amer. 1: 28. (1803) Torrey & Hooker: Ann. Lyceum Nat. Hist. New York 3: 437, errata. (1836)
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