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savannah beaksedge

indianola beaksedge

Habit Plants perennial, cespitose, 20–45 cm; rhizomes absent. Plants perennial, cespitose, to 100 cm; rhizomes absent.
Culms

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

stiffly erect or ascending, leafy-based, triangular, multiribbed.

Leaves

exceeded by culm;

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

ascending or erect, crowded toward culm base, shorter, more widely spaced distally, longest overtopping or equaling subtended inflorescences;

principal blades flat, trigonous distally, 4–6 mm wide, apex attenuate, trigonous.

Inflorescences

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

terminal and axillary, compounds of fascicles, nearly umbellate;

clusters hemispheric to nearly capitate, 1.5–2 cm wide; 1 cluster nearly sessile, others on slender rays to 7 cm, sometimes penultimate node with single cluster on peduncle 7–12 cm.

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.

light redbrown, lanceoloid, 6–7 mm, apex acute;

fertile scales lance-ovate, 5 mm, apex acute to blunt, midrib shortexcurrent or not.

Flowers

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

perianth bristles 6, overtopping tubercle base, antrorsely barbellate.

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.

1 per spikelet, (5.5–)6–7 mm;

body obovoid, 3–4 × 2–2.5 mm, margins thick, crimped, surfaces level or concave, minutely pebbled;

tubercle narrowly conic, 2grooved, 3–4 mm, base blunt, stout, capping fruit apex, tip barely exserted.

Rhynchospora debilis

Rhynchospora indianolensis

Phenology Fruiting late spring–fall. Fruiting early summer–fall.
Habitat Sands and peats in low, open fields, bogs, seeps, low pinelands, savannas, and ditch banks Silty shallows of pools, prairie swales, ditches
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
TX
[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.)

Rhynchospora indianolensis was considered by G. Kükenthal to be closely related to, if not the same as, the Cuban R. scutellata Grisebach but with fruit of different dimensions and sculpture. W. W. Thomas (1984) believed the two to be conspecific.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 23. FNA vol. 23, p. 207.
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. fernaldii, R. filifolia, R. floridensis, R. fusca, R. globularis, R. glomerata, R. gracilenta, R. grayi, R. harperi, R. harveyi, 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
Name authority Gale: Rhodora 46: 194, plate 826, figs. 5A, B. (1944) Small: Fl. S.E. U.S., 193, 1327. (1903)
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