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

teasel-flatsedge, Wright's flatsedge

annual sedge, poorland flatsedge

Habit Herbs, perennial, rhizomatous. Herbs, annual, cespitose with fibrous roots.
Culms

trigonous, (30–)45–80 cm × (0.8–)1.2–2.2 mm, glabrous.

trigonous, (2–)6–15(–35) cm × (0.3–)1–1.8 mm, glabrous.

Leaves

flat to V-shaped, becoming trigonous apically, 15–30 cm × 0.5–3.2 mm.

1–5, flat to V-shaped, (1–)5–15(–22) cm × (0.5–)1.5–3 mm.

Inflorescences

spikes oblong-cylindric, densely spicate, ± truncate at base, (9–)12–22 × (4–)6–12 mm;

rays 2–4(–5), (1.5–)2.5–6 cm;

bracts 4–6, longest erect or nearly so, larger ones flat or V-shaped, smaller capillary, trigonous, 3–24 cm × 0.4–3.6 mm;

rachilla ± deciduous, wings 0.2–0.4 mm wide.

spikes ± digitate, ± globose, 7–40 × 10–20 mm;

rays (0–)1–6, 2–12 cm;

if absent, inflorescence a sessile cluster of (1–)3–10 spikelets;

rachis 2–5 mm;

bracts (1–)4–5(–6), ascending, V-shaped, 1–15(–20) cm × 0.5–3.5 mm;

rachilla persistent, wingless.

Spikelets

(10–)20–60, oblong to linear-lanceoloid, compressed-quadrangular, 3–9 × 2–3.4 mm;

floral scales deciduous, 2–4(–8), spreading, medially green, laterally stramineous, dull whitish or pale reddish brown, often red-dotted laterally, (3–)7–9-ribbed, ovate-lanceolate, (2–)2.2–2.8(–3) × (1–)1.2–1.8 mm, apex acute, weakly 3-dentate, mucro 0.2–0.6 mm, with apical tuft of crystalline prickles.

(1–)3–12(–16), greenish white, linear to linear-lanceoloid, compressed-quadrangular, 6–34(–40) × 2–3(–3.6) mm;

floral scales deciduous, (8–)16–36(–42), spreading, laterally whitish, greenish, or pale brownish, medially green, weakly 7–9-ribbed, laterally weakly 1–2-ribbed, most ribs medial, ovate, (2.4–)2.6–3 × (1.9–)2–2.4(–2.5) mm, apex acute to ± acute, cuspidate tip (0.3–)0.5–0.7(–0.8) mm.

Flowers

anthers 0.4–0.9 mm;

styles 1–1.4 mm;

stigmas 1–1.6 mm.

anthers 0.6–0.7 mm;

styles 0.9–1.3 mm;

stigmas 0.5–0.8 mm.

Achenes

brown, ± stipitate, broadly ellipsoid, 1.4–1.5(–1.6) × 0.8–0.9 mm, 0.1 × 0.1–0.2 mm, apex ± truncate, apiculate, surfaces papillose.

brown, stipitate to sessile, obovoid, (1–)1.2–1.4(–1.5) × 0.9–1(–1.1) mm, apex obtuse to emarginate, surfaces very finely puncticulate.

Cyperus dipsaceus

Cyperus compressus

Phenology Fruiting late summer. Fruiting summer–early fall.
Habitat Seepage slopes in montane forests Various disturbed soils
Elevation 1000–1500 m (3300–4900 ft) 0–900 m (0–3000 ft)
Distribution
from FNA
AZ; NM; Mexico
[BONAP county map]
from FNA
AL; AR; DE; FL; GA; IL; LA; MD; MO; MS; NC; NY; OH; PA; SC; TX; VA; Mexico; Central America; South America; Asia; Africa
[WildflowerSearch map]
[BONAP county map]
Source FNA vol. 23, p. 174. FNA vol. 23, p. 171.
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. 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. virens
C. acuminatus, C. aggregatus, C. alopecuroides, C. amabilis, C. articulatus, C. bipartitus, C. cephalanthus, 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. virens
Synonyms C. wrightii C. compressus var. pectiniformis, C. pectinatus, C. pectiniformis
Name authority Liebmann: Kongel. Danske Vidensk. Selsk. Skr., Naturvidensk. Math. Afd., ser. 5, 2: 219. (1850) Linnaeus: Sp. Pl. 1: 46. (1753)
Web links