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globe flatsedge, teasel sedge

southern flatsedge

Habit Herbs, perennial, single-stemmed to loosely cespitose. Herbs, perennial, rhizomatous.
Culms

basally cormlike, trigonous, (15–)30–100 cm × 0.5–3.5 mm, glabrous.

trigonous, (15–) 20–40(–65) cm × 0.5–1 mm, glabrous.

Leaves

flat to V-shaped, 10–65 cm × 3–9 mm, adaxial surface, margins minutely scabridulous.

V-shaped, (10–)20–40 cm × 0.8–2.8(–3) mm, glabrous.

Inflorescences

spikes densely globose to globose-ovoid, 8–17 mm wide;

rays 3–12, 2–12 cm, scaberous adaxially especially distally;

rachis 4–8 mm;

bracts (3–)4–7, ascending at 30(–45)°, flat, 5–35 cm × 2–9 mm;

rachilla persistent, wings 0.5–0.7 mm wide.

spike 1, densely oblong-cylindric, (15–)25–35(–40) × 12–18(–22) mm, (spikelets loosely spaced, 7–9 per 5 mm of rachis);

rays (5–)6–8(–11), 0.5–4(–7.5) cm;

bracts (4–)5–7(–8), ascending at 30º, (4–)10–30(–35) cm × (1–)2–4(–7) mm;

rachilla deciduous, wings persistent, 0.4–0.5 mm wide.

Spikelets

50–100, oblong-lanceoloid, ± terete-quadrangular, (3.5–)4–7 × 1–1.4 mm;

distal spikelet spreading or ascending;

floral scales persistent, 3–5, appressed, stramineous to brownish, 4-ribbed laterally, oblong-elliptic, 3.5–4.5 × 1–1.8 mm, membranous, apex entire or emarginate with mucro to 0.3 mm.

(20–)40–80(–100), linear, ± cylindric, scarcely compressed, (4.5–)6–9(–11) × (0.5–) 0.6–0.7(–1) mm;

floral scales persistent, (1–)2–3(–4), appressed, medially green, laterally light brown to tawny or bronze, medially (1–)3-ribbed, laterally 3-ribbed, oblong, (2.6–)2.8–3.2(–3.4) × (1–)1.2(–1.4) mm, apex acute, mucronulate, mucro to 0.1(–0.2) mm.

Flowers

anthers 0.4–0.8 mm;

styles 0.5–0.6 mm;

stigmas 1 mm.

anthers 0.6–0.8 mm;

styles (0.4–)0.6–1(–1.2) mm;

stigmas persistent on achenes, prominently exserted from floral scales, (1.5–)2–3(–4) mm.

Achenes

brown, ± stipitate, oblong, (1.5–)1.8–2.3 × 0.5–0.6(–0.7) mm (1/2 length of floral scales), apex obtuse, surfaces puncticulate.

brown to reddish brown, stipitate, narrowly oblong, 1.8–2.1 × (0.4–)0.5(–0.7) mm, stipe 0.1–0.2 × 0.1–0.2 mm, apex apiculate, acute, surfaces puncticulate.

Cyperus echinatus

Cyperus thyrsiflorus

Phenology Fruiting summer–early fall. Fruiting summer.
Habitat Disturbed, sunny sites, in mesic places, well-drained soils Dry, open woods
Elevation 0–500 m (0–1600 ft) 0–200 m (0–700 ft)
Distribution
from FNA
AL; AR; DC; DE; FL; GA; IL; IN; KS; KY; LA; MD; MO; MS; NC; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; WI; WV; West Indies
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; FL; GA; LA; TX; Mexico; South America; West Indies
[BONAP county map]
Discussion

The records for Rhode Island and Wisconsin are according to M. L. Horvat (1941); we have not seen specimens from those states.

Cyperus echinatus is usually recognized by its tight, nearly spheric spikes; it may occasionally be hard to distinguish from C. croceus and C. retrorsus. Compared to C. retrorsus, C. echinatus has larger spikelets and longer floral scales, anthers, and achenes. In contrast to C. echinatus, C. croceus has looser spikes, shorter, broader, greenish or yellowish floral scales, shorter, more ovoid achenes, and shorter anthers. Furthermore, C. echinatus is predominantly an inland species of roadsides, pastures, and other disturbed ground; C. retrorsus is primarily a coastal species and occurs in drier, sandier sites.

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

Source FNA vol. 23, p. 182. FNA vol. 23, p. 185.
Parent taxa Cyperaceae > Cyperus > subg. Cyperus Cyperaceae > Cyperus > subg. Cyperus
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. 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
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. virens
Synonyms Scirpus echinatus, C. ovularis, C. ovularis var. americanus, C. ovularis var. sphaericus, C. ovularis var. wolfii, C. wolfii, Kyllinga ovularis, Mariscus ovularis C. anceps, C. dissitiflorus, C. pallens, C. regiomontanus var. pallens, C. tribrachiatus, Mariscus dissitiflorus, Mariscus pallens, Mariscus tribrachiatus
Name authority (Linnaeus) Alph. Wood: Class-book Bot. ed. s.n.(b), 734. (1861) Junghuhn: Linnaea 6: 24. (1831)
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