Cyperus echinatus |
Cyperus elegans |
|
---|---|---|
globe flatsedge, teasel sedge |
royal flatsedge, sticky flatsedge |
|
Habit | Herbs, perennial, single-stemmed to loosely cespitose. | Herbs, perennial, cespitose, shortly rhizomatous, coarse, viscous. |
Culms | basally cormlike, trigonous, (15–)30–100 cm × 0.5–3.5 mm, glabrous. |
round to roundly trigonous, 15–80 cm × 2–4 mm, glabrous. |
Leaves | flat to V-shaped, 10–65 cm × 3–9 mm, adaxial surface, margins minutely scabridulous. |
adaxial face concave, becoming trigonous apically, 15–75 cm × 1–4 mm, margins involute. |
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. |
spikes ovoid, 10–20 mm wide; rays 3–8(–10), 0.5–12 cm; 2d order rays 0–3, 1–3 cm; bracts 3–7, horizontal to vertical, 2.5–5.5 cm × 1–4 mm, margins involute; 2d order bracts 0–3, 1–3 cm; rachilla persistent, wingless. |
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. |
3–20(–30), beige to greenish or reddish brown, strongly compressed, oblong-ellipsoid to oblong-lanceoloid, 3–15 × 2.5–3.5 mm; floral scales deciduous, 6–22, laterally pale greenish white to stramineous or reddish brown, medially pale green to yellowish green, laterally 2-ribbed, medially 3–5-ribbed, broadly ovate, (2–)2.8–3.6 × 2.4–2.6 mm, apex with slightly excurved mucro 0.2–0.3 mm, apically scabrid. |
Flowers | anthers 0.4–0.8 mm; styles 0.5–0.6 mm; stigmas 1 mm. |
anthers 0.6–1.4 mm; styles 1.2–1.5 mm; stigmas 1–1.5(–3) 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. |
dark reddish brown to black, stipitate, obovoid, faces concave, flat or subtly convex, (1.4–)1.8–2 × 0.9–1 mm, base cuneate, stipe (sometimes absent) spongy, 0.1–0.2 × 0.2–0.4 mm, apex truncate, apiculate, surfaces coarsely papillose. |
Cyperus echinatus |
Cyperus elegans |
|
Phenology | Fruiting summer–early fall. | Fruiting summer. |
Habitat | Disturbed, sunny sites, in mesic places, well-drained soils | Ditches, damp pastures, pond shores, riverbanks |
Elevation | 0–500 m (0–1600 ft) | 0–500 m (0–1600 ft) |
Distribution |
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
|
FL; LA; NM; TX; Mexico; Central America; South America
|
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. 172. |
Parent taxa | Cyperaceae > Cyperus > subg. Cyperus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | Scirpus echinatus, C. ovularis, C. ovularis var. americanus, C. ovularis var. sphaericus, C. ovularis var. wolfii, C. wolfii, Kyllinga ovularis, Mariscus ovularis | C. trachynotus |
Name authority | (Linnaeus) Alph. Wood: Class-book Bot. ed. s.n.(b), 734. (1861) | Linnaeus: Sp. Pl. 1: 45. (1753) |
Web links |