The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

globe flatsedge, teasel sedge

marsh flatsedge

Habit Herbs, perennial, single-stemmed to loosely cespitose. Herbs, perennial, cespitose; rhizomes upright, 5–8 mm diam., indurate.
Culms

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

trigonous, 30–50(–80) cm × 1.8–2.5 mm, glabrous.

Leaves

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

4–7(–10), V-shaped, (20–)40–60 cm × 4.5–8 mm.

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.

heads dense, hemispheric, 7–15(–18) mm diam;

or if rays absent, heads dense, irregularly lobate, 2–3.5 cm diam.;

rays 3–6, 1–30 mm; 2d order rays infrequently present, to 5 mm;

bracts (5–)10–15(–40), horizontal to ascending at 30(–45)°, V-shaped, 6–30(–40) cm × 5–8(–10) mm.

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.

40–100, greenish white, flattened, ovoid, 3.5–5 × 3–4 mm;

floral scales (8–)12–16, uniformly light greenish to light brown, laterally 1-ribbed, medially indistinctly 3-ribbed, basally 2-keeled, oblong-spatulate, widest at or above median, 2–2.5 × (0.7–)1–1.2 mm, apex minutely mucronate, scabridulous, infrequently glabrous.

Flowers

anthers 0.4–0.8 mm;

styles 0.5–0.6 mm;

stigmas 1 mm.

stamen 1;

anthers oblong, 0.7–1 mm, connective apex subulate, prolonged 0.1–0.2 mm;

styles thick, confluent with apex of, and persistent on, achene, 0.5–0.8 mm;

stigmas 0.6–1 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, stipitate, linear, slightly curved, 1.2–1.4 × 0.2(–0.3) mm, base whitish, stipe spongy, 0.1–0.2 × 0.2 mm, apex acute, surfaces papillose.

Cyperus echinatus

Cyperus pseudovegetus

Phenology Fruiting summer–early fall. Fruiting summer.
Habitat Disturbed, sunny sites, in mesic places, well-drained soils Damp places
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; AR; DC; DE; FL; GA; IL; IN; KS; KY; LA; MA; MD; MO; NC; NJ; OK; SC; TN; TX; VA
[WildflowerSearch map]
[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.)

Cyperus pseudovegetus has been called “Cyperus vegetus Willd.” (M. L. Fernald 1950). The var. megalanthus Kükenthal of eastern Mexico and Central America recognized by M. F. Denton (1978b) is now considered a distinct species, C. megalanthus (Kükenthal) G. C. Tucker (see G. C. Tucker 1994).

Cyperus pseudovegetus is introduced in Massachusetts.

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

Source FNA vol. 23, p. 182. FNA vol. 23, p. 156.
Parent taxa Cyperaceae > Cyperus > subg. Cyperus 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. 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. 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 Scirpus echinatus, C. ovularis, C. ovularis var. americanus, C. ovularis var. sphaericus, C. ovularis var. wolfii, C. wolfii, Kyllinga ovularis, Mariscus ovularis
Name authority (Linnaeus) Alph. Wood: Class-book Bot. ed. s.n.(b), 734. (1861) Steudel: Syn. Pl. Glumac. 2: 24. (1855)
Web links