Rhynchospora fascicularis |
Rhynchospora debilis |
|
---|---|---|
fascicled beaksedge |
savannah beaksedge |
|
Habit | Plants perennial, cespitose, 100–150 cm; rhizomes absent. | Plants perennial, cespitose, 20–45 cm; rhizomes absent. |
Culms | erect to excurvedascending, narrowly linear to ± filiform, terete to obscurely trigonous, leafy, densely so toward base, stiff to rather lax. |
erect to arching or spreading, leafy, ± filiform, ± terete, stiff to rather lax. |
Leaves | overtopped by culm; blades linear, ascending, proximally flat, 1–4 mm wide, apex trigonous, subulate, tapering gradually. |
exceeded by culm; blades linearfiliform, proximally shallowly concave, 1 mm, apex tapering, trigonous, blunt or broadly acute. |
Inflorescences | spikelet clusters 1–3(–4), proximal mostly widely spaced, dense, broadly turbinate to hemispheric, to 2 cm broad; leafy bracts subulate, exceeding proximal spikelets, slightly or not exceeding most distal clusters. |
spikelet clusters 1–2, mostly compact, turbinate to hemispheric; leafy bracts setaceous, exceeding spikelet clusters. |
Spikelets | redbrown, narrowly ovoid, (3–)3.5–5 mm, apex acute; fertile scales ovate, 3–3.5(–4) mm, apex acute, mostly with cusp or mucro 0.5–1 mm. |
dark redbrown, ovoid, 2–3 mm, apex acute; fertile scales obovate, 1.5–1.7(–2) mm, apex broadly rounded or retuse, midrib excurrent as cusp or mucro to 0.5 mm. |
Flowers | bristles 5–6, from rudimentary to reaching tubercle tip, or (rarely) beyond, antrorsely barbellate. |
bristles 6 or vestigial, rarely reaching fruit midbody, antrorsely barbellate. |
Fruits | 1–3 per spikelet, (1.5–)2–2.2(–2.5) mm; body dark brown with pale center, lenticular, broadly ellipsoid to ± orbicular, (1.3–)1.5–1.7(–1.9) × 1–1.5 mm, margins pale, narrow or narrowly rounded, flowing to tubercle; surfaces dull, minutely longitudinally striate; tubercle compressed, triangular to triangularsubulate, 0.5–0.7(–0.9) mm. |
1–2 per spikelet,1.7–2 mm; body brown with large pale center, lenticular, broadly obovoid to ± orbicular, 1.2–1.5 × 1.4–1.6 mm; tubercle flat, triangular, concave-sided, 0.4–0.6 mm, sometimes apiculate. |
Rhynchospora fascicularis |
Rhynchospora debilis |
|
Phenology | Fruiting late spring–fall or all year (south). | Fruiting late spring–fall. |
Habitat | Sands and peats of interdunal swales, depressions in savannas, open flatwoods, and seep-bog edges | Sands and peats in low, open fields, bogs, seeps, low pinelands, savannas, and ditch banks |
Elevation | 0–100 m (0–300 ft) | 0–200 m (0–700 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; VA; Central America; Bermuda
|
AL; FL; GA; LA; MS; NC; SC; TX; VA |
Discussion | In her revision, S. Gale (1944) treated var. distans as the more slender version of the species, one with a smaller inflorescence, more distinctly margined fruit body, and consistently elongate perianth bristles. All those character states appear to vary independently over the total range of the species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Rhynchospora debilis is very similar to R. wrightiana except it has smaller spikelet clusters and more depressed fruit tubercles. It is a common invader of cutover and bulldozed low pineland where it assumes a lowspreading habit, its many culms radiating from the common center much like spokes in a wheel. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 239. | FNA vol. 23. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Schoenus fascicularis, Dichromena distans, Phaeocephalum fasciculare, Phaeocephalum distans, R. distans, R. distans var. fascicularis, R. dommucensis, R. fascicularis var. distans, Schoenus distans | R. fascicularis var. debilis |
Name authority | (Michaux) Vahl: Enum. Pl. 2: 234. (1805) | Gale: Rhodora 46: 194, plate 826, figs. 5A, B. (1944) |
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