Rhynchospora pusilla |
Rhynchospora chapmanii |
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Chapman's beaksedge |
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Habit | Plants perennial, densely cespitose, 15–50(–60) cm; rhizomes absent. | Plants perennial, densely cespitose, 30–50(–70) cm; rhizomes absent. |
Culms | erect or arching, leafy toward base, filiform, terete, wiry. |
erect to excurved, filiform, leafy, stiff to lax. |
Leaves | overtopped by culm; blades linear to filiform, channeled, 0.3–0.5 mm wide, margins deeply involute, apex setaceous. |
mostly slightly exceeded by culm; blades ± filiform, proximally flat to concave, distally tapering, to 1 mm wide, margins involute, apex trigonous, subulate. |
Inflorescences | spikelet clusters 1–2(–3), dense to open, narrowly to broadly turbinate; branches capillary, variously elongate; leafy bracts setaceous, equaling or exceeding clusters. |
terminal; spikelet clusters 1(–2), dense, broadly turbinate to hemispheric; longer leafy bracts 1–2(–several), setaceous, overtopping inflorescence. |
Spikelets | variously brown, ellipsoid, 2–3 mm, apex sharply acute; fertile scales ovate to nearly orbiculate, rounded, 1.2–1.8 mm, apiculate, convexcupulate, midrib slender, mostly included. |
light brown, narrowly ovoid, 2–2.5(–3) mm, apex acute or acuminate; fertile scales 1.5–2(–2.5) mm, apex acute, midrib excurrent as cusp or awn 0.5–0.9 mm. |
Flowers | perianth absent. |
bristles absent, rarely reduced to nubbins, or rarely 1, then shorter than fruit body. |
Fruits | 2–3 per spikelet, 0.7–0.9(–1) mm; body pale, obovoid-lenticular, (0.5–)0.6–0.9 × 0.4–0.5 mm, margin wirelike; surfaces transversely rugulose; tubercle buttonlike, depressed triangular, 0.05–0.1 mm, base lunate atop rounded fruit body. |
1 per spikelet, 1–1.8 mm; body with dark brown ends, broad pale midzone, lenticular, ± orbicular, 1–1.2 × 0.8–1 mm, surfaces smooth; margins sharp, flowing to tubercle; tubercle lowtriangular, 0.2–0.3(–0.5) mm, sometimes apiculate. |
Rhynchospora pusilla |
Rhynchospora chapmanii |
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Phenology | Fruiting summer–fall. | Fruiting summer–fall; |
Habitat | Moist sands, peats and silts of low meadows, savannas, bogs, seeps, pond shores | |
Elevation | 0–300 m (0–1000 ft) | 0–200 m (0–700 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; Mexico; Central America; West Indies |
AL; FL; GA; LA; MS; NC; SC
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Discussion | Rhynchospora chapmanii is a frequent invader of logged or otherwise disturbed pine savannas, often an aspect dominant. Its pale inflorescences are conspicuous masses in autumn. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 220. | FNA vol. 23, p. 234. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Phaeocephalum pusillum, R. intermixta | Phaeocephalum chapmanii |
Name authority | Chapman ex M. A. Curtis: Amer. J. Sci. Arts, ser. 2, 7: 409. (1849) | M. A. Curtis: Amer. J. Sci. Arts, ser. 2, 7: 409. (1849) |
Web links |