Cyperus echinatus |
Cyperus sphacelatus |
|
---|---|---|
globe flatsedge, teasel sedge |
roadside flatsedge |
|
Habit | Herbs, perennial, single-stemmed to loosely cespitose. | Herbs, annual or perennial, cespitose. |
Culms | basally cormlike, trigonous, (15–)30–100 cm × 0.5–3.5 mm, glabrous. |
trigonous, 15–60 cm × 1–3 mm, glabrous. |
Leaves | flat to V-shaped, 10–65 cm × 3–9 mm, adaxial surface, margins minutely scabridulous. |
2–6, flat to V-shaped, 6–30(–40) cm × 2–4 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. |
spikes broadly ellipsoid, 5–45 × 10–30(–45) mm; rays (2–)5–9, (0.3–)3–10 cm; rachis 4–17 mm; bracts 5–6, horizontal to ascending, V-shaped, 1.5–30 cm × 0.5–4 mm; rachilla persistent, wings hyaline, 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. |
5–30, pale greenish white or stramineous, compressed, linear-lanceoloid, 7–35 × (1.2–)1.4–2 mm; floral scales deciduous, 6–34, spreading or appressed, laterally greenish white, often reddish or brown speckled, medially green, laterally 3–5-ribbed, medially 3-ribbed, elliptic, (2.2–)3–4(–4.4) × (1.2–)1.8–2.2 mm, apex acute. |
Flowers | anthers 0.4–0.8 mm; styles 0.5–0.6 mm; stigmas 1 mm. |
anthers 0.6 mm; styles 0.6–1.2 mm; stigmas 1–1.4(–1.7) 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. |
reddish brown to dark brown, stipitate, narrowly ellipsoid, 1.4–2 × 0.6–0.9 mm, apex apiculate, surfaces puncticulate. |
Cyperus echinatus |
Cyperus sphacelatus |
|
Phenology | Fruiting summer–early fall. | Fruiting summer. |
Habitat | Disturbed, sunny sites, in mesic places, well-drained soils | Disturbed, wet soils |
Elevation | 0–500 m (0–1600 ft) | 0 m (0 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; Central America; South America; West Indies; Africa [Introduced in North 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. 170. |
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. balbisii |
Name authority | (Linnaeus) Alph. Wood: Class-book Bot. ed. s.n.(b), 734. (1861) | Rottbøll: Descr. Pl. Rar., 21. (1772) |
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