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savannah beaksedge

Fernald's beaksedge

Habit Plants perennial, cespitose, 20–45 cm; rhizomes absent. Plants perennial, cespitose, 15–50 cm; rhizomes absent.
Culms

erect to arching or spreading, leafy, ± filiform, ± terete, stiff to rather lax.

erect or ascending, slender, leafy proximal to middle, somewhat stiff.

Leaves

exceeded by culm;

blades linearfiliform, proximally shallowly concave, 1 mm, apex tapering, trigonous, blunt or broadly acute.

overtopped by culm;

blades ascending, ± filiform, proximally flat or slightly concave, to 1 mm wide, apex narrowing, trigonous, abruptly blunt.

Inflorescences

spikelet clusters 1–2, mostly compact, turbinate to hemispheric; leafy bracts setaceous, exceeding spikelet clusters.

spikelet clusters 1–2, if 2 then close together, dense, broadly turbinate to hemispheric or even globose;

primary leafy bract setaceous, exceeding clusters.

Spikelets

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.

redbrown, ovoid, 2–2.5(–4) mm, apex acute;

fertile scales broadly ovate, 1.5–1.9(–2) mm, apex acute to acuminate, midrib excurrent as awn to 0.5 mm.

Flowers

bristles 6 or vestigial, rarely reaching fruit midbody, antrorsely barbellate.

bristles 6, some reaching to apex of fruit body.

Fruits

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.

2–3 per spikelet, 1–1.2(–1.4) mm;

body dull dark brown with paler brown center, lenticular, broadly obovoid to broadly ellipsoid, 1 × 0.8 mm, margins narrow, flowing to tubercle;

tubercle nearly equilaterally triangular, 0.2–0.3 mm.

Rhynchospora debilis

Rhynchospora fernaldii

Phenology Fruiting late spring–fall. Fruiting summer–fall.
Habitat Sands and peats in low, open fields, bogs, seeps, low pinelands, savannas, and ditch banks Sands and peats of low clearings in flatwoods, savannas, and bog edges
Elevation 0–200 m (0–700 ft) 0–100 m (0–300 ft)
Distribution
from FNA
AL; FL; GA; LA; MS; NC; SC; TX; VA
[BONAP county map]
from FNA
AL; FL; GA; MS
[BONAP county map]
Discussion

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. FNA vol. 23, p. 235.
Parent taxa Cyperaceae > Rhynchospora Cyperaceae > Rhynchospora
Sibling taxa
R. alba, R. baldwinii, R. brachychaeta, R. breviseta, R. caduca, R. californica, R. capillacea, R. capitellata, R. careyana, R. cephalantha, R. chalarocephala, R. chapmanii, R. ciliaris, R. colorata, R. compressa, R. corniculata, R. crinipes, R. curtissii, R. decurrens, R. divergens, R. elliottii, R. eximia, R. fascicularis, R. fernaldii, R. filifolia, R. floridensis, R. fusca, R. globularis, R. glomerata, R. gracilenta, R. grayi, R. harperi, R. harveyi, R. indianolensis, R. inexpansa, R. inundata, R. knieskernii, R. kunthii, R. latifolia, R. macra, R. macrostachya, R. megalocarpa, R. megaplumosa, R. microcarpa, R. microcephala, R. miliacea, R. mixta, R. nitens, R. nivea, R. odorata, R. oligantha, R. pallida, R. perplexa, R. pineticola, R. pleiantha, R. plumosa, R. punctata, R. pusilla, R. rariflora, R. recognita, R. scirpoides, R. solitaria, R. stenophylla, R. thornei, R. torreyana, R. tracyi, R. wrightiana
R. alba, R. baldwinii, R. brachychaeta, R. breviseta, R. caduca, R. californica, R. capillacea, R. capitellata, R. careyana, R. cephalantha, R. chalarocephala, R. chapmanii, R. ciliaris, R. colorata, R. compressa, R. corniculata, R. crinipes, R. curtissii, R. debilis, R. decurrens, R. divergens, R. elliottii, R. eximia, R. fascicularis, R. filifolia, R. floridensis, R. fusca, R. globularis, R. glomerata, R. gracilenta, R. grayi, R. harperi, R. harveyi, R. indianolensis, R. inexpansa, R. inundata, R. knieskernii, R. kunthii, R. latifolia, R. macra, R. macrostachya, R. megalocarpa, R. megaplumosa, R. microcarpa, R. microcephala, R. miliacea, R. mixta, R. nitens, R. nivea, R. odorata, R. oligantha, R. pallida, R. perplexa, R. pineticola, R. pleiantha, R. plumosa, R. punctata, R. pusilla, R. rariflora, R. recognita, R. scirpoides, R. solitaria, R. stenophylla, R. thornei, R. torreyana, R. tracyi, R. wrightiana
Synonyms R. fascicularis var. debilis R. fascicularis var. fernaldii
Name authority Gale: Rhodora 46: 194, plate 826, figs. 5A, B. (1944) Gale: Rhodora 46: 182, plate 825, figs. 3A, B. (1944)
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