Rhynchospora megalocarpa |
Rhynchospora harveyi |
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sandyfield beaksedge |
Harvey's beaksedge |
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Habit | Plants perennial, cespitose, to 130 cm, coarse; rhizomes scaly, stoloniferous, stout. | Plants perennial, cespitose, 70–110 cm; rhizomes absent. | ||||
Culms | erect to arching, leafy, trigonous, slender, firm. |
erect to excurved, leafy, obscurely trigonous, slender. |
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Leaves | overtopped by culms; blades linear, proximally flat, 3–7 mm wide, apex trigonous, subulate, tapering. |
spreading to ascending, shorter than culm, crowded toward culm base; blades linear, proximally flat, 1–3 mm wide, gradually involute, apically trigonous, subulate. |
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Inflorescences | spikelet clusters 2–6, sparse, widely spaced, turbinate; peduncles and branches ascending; leafy bracts exceeding proximal clusters. |
spikelet clusters 1–4, dense to open, mostly irregularly turbinate; peduncles ascending, branches spreading to erect, ultimate branches with many spikelets; leafy bracts setaceoustipped, usually exceeding all clusters, or at least all but the distal. |
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Spikelets | light redbrown, ovoid to ellipsoid, (4–)5–8(–9) mm, apex acute or acuminate; fertile scales ovate, (5.5–)6–6.5(–7) mm, midrib included or shortexcurrent. |
light redbrown or brown, broadly ellipsoid to lanceoloid, 3–4 mm, apex acute to acuminate; fertile scales ovate to obovate or suborbiculate, 2–3.5 mm apex acute to rounded or emarginate, midrib included or exserted as mucro. |
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Flowers | perianth bristles 6(–8), mostly reaching from fruit midbody to tubercle base, antrorsely barbellate. |
perianth bristles mostly 6, rarely reaching fruit midbody, antrorsely barbellate. |
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Fruits | 1–2 per spikelet, (3.5–)4–5 mm; body dark brown to mahogany or nearly black, broadly obovoid, tumid, nearly smooth, buttressed to tubercle; tubercle lowconic, rimmed, 0.7(–1) mm, apex apiculate. |
mostly 1 per spikelet, 2–2.5 mm, body dark brown, obovoid to subglobose, tumid or lenticular, 1.5–1.7 mm, transversely finely rugose to nearly level, intervals with very small, pitlike alveoli. |
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Rhynchospora megalocarpa |
Rhynchospora harveyi |
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Phenology | Fruiting summer–fall. | |||||
Habitat | White or yellow sandhills | |||||
Elevation | 0–300 m (0–1000 ft) | |||||
Distribution |
AL; FL; GA; MS; NC; SC
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AL; AR; FL; GA; KS; LA; MO; MS; NC; OK; SC; TN; TX; VA; se United States; Midwestern |
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Discussion | The perianth in Rhynchospora megalocarpa is unusual. The receptacular joint is stubby, bearing staggered cycles of bristles that vary extremely in length and number—on a par with R. alba, R. baldwinii, and R. macra in numbers of bristles. The greatest extreme is twelve, the fewest as low as two; usually if the number is low, the remaining sites for bristles will be dark-colored nubbins. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 2 (2 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 23, p. 230. | FNA vol. 23, p. 231. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Phaeocephalum dodecandrum, R. dodecrandra, R. pycnocarpa | |||||
Name authority | A. Gray: Ann. Lyceum Nat. Hist. New York 3: 208. (1835) | W. Boott: Bot. Gaz. 9: 85. (1884) | ||||
Web links |