Rhynchospora fernaldii |
Rhynchospora alba |
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Fernald's beaksedge |
rhynchospore blanc, white beak-rush, white beaksedge |
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Habit | Plants perennial, cespitose, 15–50 cm; rhizomes absent. | Plants perennial, densely cespitose, 6–75 cm; rhizomes mostly absent. |
Culms | erect or ascending, slender, leafy proximal to middle, somewhat stiff. |
erect to curved, leafy, obscurely trigonous to nearly terete, few ribbed, slender. |
Leaves | overtopped by culm; blades ascending, ± filiform, proximally flat or slightly concave, to 1 mm wide, apex narrowing, trigonous, abruptly blunt. |
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Inflorescences | spikelet clusters 1–2, if 2 then close together, dense, broadly turbinate to hemispheric or even globose; primary leafy bract setaceous, exceeding clusters. |
clusters 1 or 2–3, then widely spaced, narrowly turbinate to hemispheric, 1.5–2.5 cm wide; subtending leafy bracts often exceeded by distal cluster. |
Spikelets | redbrown, ovoid, 2–2.5(–4) mm, apex acute; fertile scales broadly ovate, 1.5–1.9(–2) mm, apex acute to acuminate, midrib excurrent as awn to 0.5 mm. |
pale brown to nearly white, ellipsoid, 3.5–5.5 mm, apex acute; fertile scales elliptic, 3–3.5(–4) mm, apex acute or acuminate, midrib excurrent as mucro. |
Flowers | bristles 6, some reaching to apex of fruit body. |
perianth bristles 10–12, slightly overtopping tubercle, retrorsely barbellate or rarely smooth, base often setose. |
Fruits | 2–3 per spikelet, 1–1.2(–1.4) mm; body dull dark brown with paler brown center, lenticular, broadly obovoid to broadly ellipsoid, 1 × 0.8 mm, margins narrow, flowing to tubercle; tubercle nearly equilaterally triangular, 0.2–0.3 mm. |
1(–2) per spikelet, (2.3–)2.5–3 mm; body pale brown with paler center, stipitateobovoid, lenticular, 1.5–1.8(–2) × 0.9–1.2 mm; surfaces transversely striate, relatively smooth, rim narrow, flowing to tubercle base; tubercle narrowly triangularsubulate, 0.5–1.2 mm. |
Principal | leaves mostly overtopped by culm; blades narrowly linear to filiform, proximally flat, 0.5–1.5 mm, apex tapering, trigonous. |
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Rhynchospora fernaldii |
Rhynchospora alba |
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Phenology | Fruiting summer–fall. | Fruiting summer–fall. |
Habitat | Sands and peats of low clearings in flatwoods, savannas, and bog edges | Acid, sphagnous, boggy, open sites, poor fens, often on floating mats or peaty interstices of rocky shores |
Elevation | 0–100 m (0–300 ft) | 0–2000 m (0–6600 ft) |
Distribution |
AL; FL; GA; MS |
AK; CA; CT; DE; GA; ID; IL; IN; MA; MD; ME; MI; MN; NC; NH; NJ; NY; OH; OR; PA; RI; SC; TN; VA; VT; WA; WI; WV; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK; Fla(?); West Indies (Puerto Rico); South America(?); Eurasia
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Discussion | The smooth-bristled Rhynchospora alba forma laeviseta Gale mostly occurs with the typical antrorsely barbellate type in Pennsylvania, the Great Lakes, British Columbia, Newfoundland, and Nova Scotia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 235. | FNA vol. 23, p. 214. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | R. fascicularis var. fernaldii | Schoenus albus, Dichromena alba, Phaeocephalum album, R. luguillensis, Triodon albus |
Name authority | Gale: Rhodora 46: 182, plate 825, figs. 3A, B. (1944) | (Linnaeus) Vahl: Enum. Pl. 2: 236. (1805) |
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