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ovate spike-rush, ovoid spike-rush, ovoid spikesedge, éléocharide ovale

black-fruit spike-rush, black-fruit spikesedge

Culms

2–35 cm × 0.3–1 mm.

to 2 times wider than thick, 35–60(–70) cm × 0.5–1.3 mm, hard, usually with to 10 blunt ribs, at 20X often finely ridged and minutely granular.

Leaves

apex of distal leaf sheath obtuse to acute, tooth to 0.2 mm.

distal leaf sheaths brown to reddish.

Spikelets

ovoid, 2–8 × 2–4 mm, apex acute (to blunt);

floral scales 25–100+, ca. 10 per mm of rachilla, orange-brown, rarely stramineous, ovate, 1.5–2 × 1 mm, midribs often keeled in distal part of spikelet, apex rounded to subacute.

3–12 × 3–4 mm;

proximal scale amplexicaulous, 3.5–4 mm, midrib region very broad and fleshy, apex entire;

subproximal scale with a flower;

floral scales 30–40, 8–10 per mm of rachilla, orange-brown to stramineous, midrib region stramineous, broadly ovate, papery or sometimes membranous, 3–4 × 2 mm, apex entire, rounded.

Flowers

perianth bristles present, rarely absent, (5–)6–7, brown, fairly slender, exceeding tubercle;

stamens 2(–3);

anthers brown, 0.3 mm;

styles 2-fid or some 3-fid.

perianth bristles present, sometimes rudimentary, brown, length variable, obscurely retrorsely spinulose;

anthers brown, 1.7–2.2 mm.

Achenes

0.75–1 × 0.6–0.85 mm.

subdeltoid in outline, sometimes broadly obpyriform, equilaterally trigonous, angles prominent, 0.9–1.2 × 0.7–1.1 mm, apex truncate.

Tubercles

deltoid, 0.3–0.5 × 0.3–0.5 mm, 3/5 of to as high as wide, 1/3–2/3 as high and 1/2–3/4 as wide as achene.

sessile, depressed-pyramidal, often apiculate, as wide as achene, 0.3–0.5 × 0.7–1.1 mm.

2n

= 10.

Eleocharis ovata

Eleocharis melanocarpa

Phenology Fruiting summer–fall. Fruiting summer.
Habitat Fresh, often drying shores, lake and stream beds, bogs, tidal estuaries, disturbed places Fresh, oligotrophic, acid, sandy or peaty, often drying shores, ponds, ditches
Elevation 10–700 m (East), 1500–2000 m (Arizona) (0–2300 ft (East), 4900–6600 ft (Arizona)) 10–300 m (0–1000 ft)
Distribution
from FNA
AZ; CT; IA; IL; IN; KY; MA; ME; MI; MN; MO; NH; NJ; NY; OH; OK; OR; PA; VA; VT; WA; WI; WV; AB; BC; NB; NL; NS; ON; PE; QC; Eurasia
[WildflowerSearch map]
from FNA
AL; FL; GA; IN; MA; MI; NC; NY; RI; SC; TX; VA
[WildflowerSearch map]
[BONAP county map]
Discussion

Although Eleocharis ovata has often been confused with E. obtusa, B. M. H. Larson and P. M. Catling (1996) showed that these species may be distinguished by non-overlapping widths of the tubercles, at least in Canada. The records of E. ovata in New Brunswick, Newfoundland, Nova Scotia, and Prince Edward Island are based on B. M. H. Larson and P. M. Catling (1996) and the records in Illinois, Indiana, Missouri, Montana, New Jersey, Oregon, and Washington are based on D. M. Hines (1975). Eleocharis ovata probably also occurs in Manitoba and Saskatchewan.

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

Eleocharis melanocarpa is reported from Rhode Island; I have not seen a voucher specimen.

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

Source FNA vol. 23, p. 103. FNA vol. 23, p. 89.
Parent taxa Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleogenus > ser. Ovatae Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Melanocarpae
Sibling taxa
E. acicularis, E. aestuum, E. albida, E. ambigens, E. atropurpurea, E. baldwinii, E. bella, E. bernardina, E. bicolor, E. bifida, E. bolanderi, E. brachycarpa, E. brittonii, E. cancellata, E. cellulosa, E. coloradoensis, E. compressa, E. cylindrica, E. decumbens, E. diandra, E. elliptica, E. elongata, E. engelmannii, E. equisetoides, E. erythropoda, E. fallax, E. flavescens, E. geniculata, E. intermedia, E. interstincta, E. kamtschatica, E. lanceolata, E. macrostachya, E. mamillata, E. melanocarpa, E. microcarpa, E. minima, E. montana, E. montevidensis, E. nana, E. nigrescens, E. nitida, E. obtusa, E. obtusetrigona, E. occulta, E. pachycarpa, E. palustris, E. parishii, E. parvula, E. quadrangulata, E. quinqueflora, E. radicans, E. ravenelii, E. retroflexa, E. reverchonii, E. robbinsii, E. rostellata, E. suksdorfiana, E. tenuis, E. torticulmis, E. tortilis, E. tricostata, E. tuberculosa, E. uniglumis, E. vivipara, E. wolfii
E. acicularis, E. aestuum, E. albida, E. ambigens, E. atropurpurea, E. baldwinii, E. bella, E. bernardina, E. bicolor, E. bifida, E. bolanderi, E. brachycarpa, E. brittonii, E. cancellata, E. cellulosa, E. coloradoensis, E. compressa, E. cylindrica, E. decumbens, E. diandra, E. elliptica, E. elongata, E. engelmannii, E. equisetoides, E. erythropoda, E. fallax, E. flavescens, E. geniculata, E. intermedia, E. interstincta, E. kamtschatica, E. lanceolata, E. macrostachya, E. mamillata, E. microcarpa, E. minima, E. montana, E. montevidensis, E. nana, E. nigrescens, E. nitida, E. obtusa, E. obtusetrigona, E. occulta, E. ovata, E. pachycarpa, E. palustris, E. parishii, E. parvula, E. quadrangulata, E. quinqueflora, E. radicans, E. ravenelii, E. retroflexa, E. reverchonii, E. robbinsii, E. rostellata, E. suksdorfiana, E. tenuis, E. torticulmis, E. tortilis, E. tricostata, E. tuberculosa, E. uniglumis, E. vivipara, E. wolfii
Synonyms Scirpus ovatus, E. obtusa var. ovata, E. ovata var. heuseri
Name authority (Roth) Roemer & Schultes: in J. J. Roemer et al., Syst. Veg. 2: 152. (1817) Torrey: Ann. Lyceum Nat. Hist. New York 3: 311. (1836)
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