Rhynchospora tracyi |
Rhynchospora caduca |
|
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Tracy's beaksedge |
anglestem beaksedge |
|
Habit | Plants perennial, clonal, to 120 cm; rhizomes scaly, slender, less than 2 mm thick. | Plants perennial, cespitose, 70–150 cm; rhizomes often present, short, scaly. |
Culms | erect, leafybased, wandlike, nearly terete, multiribbed. |
erect or ascending, leafy, trigonous. |
Leaves | ascending or erect, longest nearly equaling culm; principal blades linear, involutecylindric, to 3 mm wide, apex tapering, subulate. |
exceeded by culm; blades linear, proximally 4–7 mm wide, apex trigonous, tapering. |
Inflorescences | terminal, heads 1–4, dense, macelike, 1–1.5 mm thick; involucral bracts leafy, proximalmost overtopping inflorescence. |
terminal and axillary; clusters 3–6, mostly dense, narrowly to broadly turbinate, branches ascending; leafy bracts exceeeding proximalmost inflorescences. |
Spikelets | greenish, lanceovoid, 5–6 mm, apex acuminate; fertile scales boat-shaped, 5 mm, apex acute to shortacuminate, midrib slightly excurrent or not. |
rich brown, ovoid, (3–)4–5 mm, apex acuminate; fertile scales ovate, 2.5–3.5 mm, apex acuminate, midrib included or shortexcurrent. |
Flowers | perianth bristles 6, exceeding fruit body, antrorsely barbellate. |
perianth bristles mostly 6, exceeding tubercle tip. |
Fruits | 1 per spikelet, 6–8(–8.7) mm; body pale greenbrown, laterally compressed, obcordiform, 2.5–3(–4) mm, margins thick, rounded, not crimped, apex barely exserted, setulose, surfaces nearly plane, minutely cancellate (latticed); tubercle (style base) linear, angled, 4–6 mm, much narrower than fruit summit, setulose. |
mostly 3–4 per spikelet, 2–2.2 mm; body brown on short pedicellar (to 0.3 mm) stalk, broadly obovoid, lenticular, 1.3–1.5 × 1–1.5 mm, surfaces transversely rugulose, vertically finely striate and rectangularalveolate; tubercle compressed, triangular acuminate, 0.5–0.8 mm, edges setulose. |
Rhynchospora tracyi |
Rhynchospora caduca |
|
Phenology | Fruiting late spring–fall. | Fruiting summer–fall. |
Habitat | Emergent in shallows of cypress domes, marshes and swales, ditches and ponds | Low meadows, clearings, marshes, marsh borders, seeps, bog moats, savannas, ditches, pine flatwoods, swamps |
Elevation | 0–100 m (0–300 ft) | 0–400 m (0–1300 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; West Indies; Central America (Belize)
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AL; AR; FL; GA; LA; MS; NC; OK; SC; TN; TX; VA
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Discussion | Rhynchospora tracyi frequently forms clones extending for acres by means of its long slender rhizomes. Its wandlike, terete, supple culms, and round-capitate clusters of spikelets suggest a rush more than a sedge. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Rhynchospora caduca has its closest relationships with the even more robust R. odorata Grisebach, on the one hand, and the swampinhabiting, more slender, and rhizomatous R. mixta Britton ex Small, on the other. Intergrades with R. odorata appear in Alabama and northwest Florida; intergrades with R. mixta appear where ranges overlap in both the Atlantic and Gulf coastal plains. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 207. | FNA vol. 23, p. 223. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Ceratoschoenus capitatus, Phaeocephalum tracyi, Schoenus triceps | Phaeocephalum caducum, R. patula |
Name authority | Britton: Trans. New York Acad. Sci. 11: 84. (1892) | Elliott: Sketch Bot. S. Carolina 1: 62. (1816) |
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