Rhynchospora miliacea |
Rhynchospora alba |
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millet beaksedge |
rhynchospore blanc, white beak-rush, white beaksedge |
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Habit | Plants perennial, cespitose, to 150 cm; rhizomes stoloniferous, slender. | Plants perennial, densely cespitose, 6–75 cm; rhizomes mostly absent. |
Culms | lax, leafy, wandlike, ± terete to obscurely angled, slender. |
erect to curved, leafy, obscurely trigonous to nearly terete, few ribbed, slender. |
Leaves | ascending, exceeded by culms; blades flat, 4–7(–10) mm wide, apex trigonous, shortacuminate, tapering. |
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Inflorescences | spikelet clusters 4–6 or more, equidistant along culm on ascending peduncles, branches capillary, divaricate, clusters loose, diffuse, rounded. |
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 | light brown, ellipsoid to lanceoloid or ovoid, 2.5–3.5 mm, apex acute; fertile scales ovate, (1.5–)2–3 mm, apex rounded or acute, midrib forming apiculus. |
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 | perianth bristles 6, longest exceeding tubercle, antrorsely barbellate. |
perianth bristles 10–12, slightly overtopping tubercle, retrorsely barbellate or rarely smooth, base often setose. |
Fruits | 2–several per spikelet, 1.3–1.5 mm; body pale brown, broadly obovoid, tumidly biconvex, 1.1–1.2 × 1–1.1 mm; surfaces transversely sharply wavyrugulose, intervals with vertical, rectangular, shallow alveolae; tubercle depressedconic, slightly compressed, 0.2–0.3(–0.4) mm, edges setulose. |
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 miliacea |
Rhynchospora alba |
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Phenology | Fruiting summer–fall. | Fruiting summer–fall. |
Habitat | Sandy alluvium of swamp forests and gallery forests, low clearings forests | Acid, sphagnous, boggy, open sites, poor fens, often on floating mats or peaty interstices of rocky shores |
Elevation | 0–400 m (0–1300 ft) | 0–2000 m (0–6600 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; VA; West Indies
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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 ultimate branches in Rhynchospora miliacea typically terminate in only one or two spikelets, the scales of which fall quickly, and the exposed fruits look like short miniature strings of beads. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 23, p. 226. | FNA vol. 23, p. 214. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Schoenus miliaceus, Phaeocephalum miliaceum, R. sparsa, Schoenus sparsus | Schoenus albus, Dichromena alba, Phaeocephalum album, R. luguillensis, Triodon albus |
Name authority | (Lamarck) A. Gray: Ann. Lyceum Nat. Hist. New York 3: 198. (1835) | (Linnaeus) Vahl: Enum. Pl. 2: 236. (1805) |
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