Cyperus retrorsus |
Cyperus fendlerianus |
|
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pine barren flatsedge |
Fendler flatsedge, Fendler's flatsedge, Fendler's nutgrass, Fendler's sedge |
|
Habit | Herbs, perennial, cespitose, shortly rhizomatous. | Herbs, perennial, rhizomatous. |
Culms | trigonous, 20–50(–85) cm × 1–2(–4) mm, glabrous. |
trigonous, (7–)20–70(–85) cm × (0.5–)1–1.8(–2.6) mm, glabrous or sparsely to densely scabridulous on surfaces or on angles immediately proximal to inflorescence in distal 3–6 cm. |
Leaves | 3–6(–10), 10–40(–55) cm × 1.5–4(–5) mm, V- to inversely W-shaped. |
2–3, flat to V-shaped, (12–)20–40(–55) cm × (2–)3–5(–7) mm. |
Inflorescence(s) | spike 1, densely oblong-ovoid often with small basal branches, 8–16 × 4–12(–16) mm; rays 4–8(–11), 0.5–3.5(–8.5) cm; bracts (3–)4–6(–10), ascending at (30–)45°, flat to broadly V-shaped, (4–)14–30(–55) cm × 1–5 mm, scabridulous along margins only; rachilla deciduous, wings persistent, 0.2–0.3 mm wide. |
spikes (1–)3–4(–6), largest erect, others at base of central spike, erect spike sessile, loosely to densely cylindric to ovoid-cylindric, (12–)18–30 × (6–)12–20 mm, remaining spikes 1/2 as large; rays absent; bracts (2–)3–6(–10), ± horizontal to reflexed parallel to culm, (2–)6–16(–25) cm × (1.5–)2–4(–7) mm; rachilla ± deciduous, wingless. |
Spikelets | 40–120, oblong-lanceoloid, subterete, 2.2–4(–4.5) × 0.8–1.6 mm; distal spikelet spreading or ascending; floral scales persistent, 2–5, appressed, brown to stramineous, or fuscous and lustrous, medially greenish and 1(–3)-ribbed, laterally greenish to yellowish white and 3–4-ribbed, oblong to oblong-lanceolate, 1.8–2.5 × 1–1.5 mm, subcoriacous. |
(8–)15–30, spreading to ascending-appressed, oblong-lanceoloid, quadrangular, slightly compressed, 5–8(–10) × (2–)2.4–3.4(–4.2) mm; floral scales (2–)4–6(–8), yellowish, reddish, or greenish brown, medially greenish, straight to excurved, laterally (2–)3–4(–5)-ribbed, medially (1–)3–(–5)-ribbed, ovate-orbiculate, 2.4–2.8(–3.4) × 2.4–2.8(–3.4) mm, apex obtuse, mucronate to cuspidate, stout, (0.1–)0.3–0.6 mm, medially glabrous. |
Flowers | anthers 0.3–0.5 mm; styles 0.5–0.8 mm; stigmas 0.6–0.9 mm. |
anthers 0.4–0.8 mm; styles 0.7–1.3 mm; stigmas 0.7–1.2 mm. |
Achenes | brown, oblong-ellipsoid, 1.2–1.7 × 0.5–0.6 mm, base cuneate, apex subacute, surfaces papillose. |
finely reticulate, brown to reddish brown, ± stipelike, obovoid, 1.6–1.9 × 1.1–1.4(–1.6) mm, base attenuate to cuneate, 0.1–0.2 × 0.2 mm, apex obtuse, apiculate, surfaces glabrous. |
Cyperus retrorsus |
Cyperus fendlerianus |
|
Phenology | Fruiting summer (Jun–Aug). | Fruiting summer. |
Habitat | Open woods and thickets in moist to dry, sandy soils | Clearings in montane forests |
Elevation | 0–1000 m (0–3300 ft) | 500–1800 m (1600–5900 ft) |
Distribution |
AL; AR; DC; DE; FL; GA; LA; MD; MO; MS; NC; NJ; NY; OK; SC; TN; TX; VA; Mexico (Tamaulipas)
|
AZ; CO; NM; TX; WY; Mexico
|
Discussion | Cyperus retrorsus was reported in Indiana (M. L. Horvat 1941); we have been unable to confirm the report. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Hybridization between Cyperus fendlerianus and C. sphaerolepis occurs occasionally in the southwestern United States and northern Mexico (B. G. Marcks 1972). The unnamed hybrid appears to be fully fertile and can be recognized by morphologic intermediacy. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 187. | FNA vol. 23, p. 177. |
Parent taxa | Cyperaceae > Cyperus > subg. Cyperus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | Mariscus cylindricus, C. cylindricus, Mariscus retrorsus | Chlorocyperus fendlerianus |
Name authority | Chapman: Bot. Gaz. 3: 17. (1878) | Boeckeler: Linnaea 35: 520. (1868) |
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