View source for Eleocharis obtusa

{{Treatment/ID
|accepted_name=Eleocharis obtusa
|accepted_authority=(Willdenow) Schultes
|publications={{Treatment/Publication
|title=Mant.
|place=2: 89. 1824
|year=1824
}}
|common_names=Blunt spike-rush;éléocharide obtuse
|basionyms={{Treatment/ID/Synonym
|name=Scirpus obtusus
|authority=Willdenow
}}
|synonyms={{Treatment/ID/Synonym
|name=Eleocharis obtusa var. ellipsoidales
|authority=Fernald
}} {{Treatment/ID/Synonym
|name=Eleocharis obtusa var. gigantea
|authority=Fernald
}} {{Treatment/ID/Synonym
|name=Eleocharis obtusa var. jejuna
|authority=Fernald
}} {{Treatment/ID/Synonym
|name=Eleocharis obtusa var. peasei
|authority=Svenson
}}
|hierarchy=Cyperaceae;Eleocharis;Eleocharis subg. Eleocharis;Eleocharis sect. Eleogenus;Eleocharis (sect. Eleogenus) ser. Ovatae;Eleocharis obtusa
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Cyperaceae]]</div><div class="higher-taxon"><small>genus</small>[[Eleocharis]]</div><div class="higher-taxon"><small>subgenus</small>[[Eleocharis subg. Eleocharis]]</div><div class="higher-taxon"><small>section</small>[[Eleocharis sect. Eleogenus]]</div><div class="higher-taxon"><small>series</small>[[Eleocharis (sect. Eleogenus) ser. Ovatae]]</div><div class="higher-taxon"><small>species</small>[[Eleocharis obtusa]]</div></div>
|volume=Volume 23
|mention_page=page 5, 64, 65, 97, 103, 104
|treatment_page=page 105
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Culms </b>3–50(–90) cm × 0.2–2 mm. <b>Leaves</b>: apex of distal leaf sheath obtuse to acute, tooth to 0.3 mm. <b>Spikelets</b> broadly ovoid (to ellipsoid or lanceoloid), apex rounded (to acute), (2–)5–13 × (2–)3–4 mm; floral scales 15–150+, 8–20 per mm of rachilla, orange-brown (to stramineous), elliptic, 1.5–2.5 × 1–1.5 mm, midribs seldom keeled, apex broadly rounded. <b>Flowers</b>: perianth bristles (5–)6–7, rarely 0, brown, stout, slightly to usually greatly exceeding tubercle; stamens usually 3; anthers brown to yellow, 0.3–0.6 mm; styles usually 3-fid and 2-fid in same spikelet. <b>Achenes</b> 0.9–1.2(–1.3) × 0.7–0.9 mm. <b>Tubercles</b> deltoid 0.35–0.5 × (0.4–)0.5–0.8 mm, 1/3–2/3 as high as wide, 1/3–1/2 as high and 2/3–9/10 as wide as achene. <b>2n</b> = 10.</span><!--

-->{{Treatment/Body
|phenology=Fruiting summer–fall.
|habitat=Fresh shores, marshes, disturbed places
|elevation=10–1600 m
|distribution=B.C.;N.S.;Ont.;P.E.I.;Que.;Ala.;Ark.;Calif.;Colo.;Conn.;Del.;D.C.;Fla.;Ga.;Idaho;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Maine;Mass.;Mich.;Minn.;Miss.;Mo.;Nebr.;N.H.;N.J.;N.Y.;N.C.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;Tenn.;Tex.;Vt.;Va.;Wash.;W.Va.;Wis.;Wyo.;Pacific Islands (Hawaii).
|discussion=<p>Extremely uncommon plants of <i>Eleocharis obtusa</i> without perianth bristles may be called <i>E. obtusa</i> var. peasei (type from New Hampshire). Robust plants with distinct caudices, floral scales 2.5 mm, and achenes 1.2–1.3 mm (<i>Eleocharis obtusa</i> <i></i>var.<i> gigantea</i> Fernald) are rare (specimens seen from the Washington-British Columbia border [type], Arkansas, and the Hawaiian Islands). Dwarf plants (<i>E. obtusa</i> var. jejuna Fernald, type from Maine), with unusually small achenes and floral scales, and tubercles often less than 0.5 mm wide, are occasional in the East and are easily confused with <i>E. ovata</i> and <i>E. aestuum</i>. A few specimens are intermediate with <i>E. engelmannii</i>. <i>Eleocharis obtusa</i> is sometimes treated as conspecific with <i>E. ovata</i>, which consistently differs in its mostly 2-fid styles, mostly two stamens, and especially its narrower tubercles (B. M. H. Larson and P. M. Catling 1996).</p><!--
--><p><i>Eleocharis</i> macounii Fernald has been treated as a synonym of E. obutsa (H. K. Svenson 1957) but is more probably a hybrid between <i>E. intermedia</i> and <i>E. obtusa</i> (P. M. Catling and S. G. Hay 1993; see 34. <i>E. intermedia</i>).</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Eleocharis obtusa
|author=
|authority=(Willdenow) Schultes
|rank=species
|parent rank=series
|synonyms=Eleocharis obtusa var. ellipsoidales;Eleocharis obtusa var. gigantea;Eleocharis obtusa var. jejuna;Eleocharis obtusa var. peasei
|basionyms=Scirpus obtusus
|family=Cyperaceae
|phenology=Fruiting summer–fall.
|habitat=Fresh shores, marshes, disturbed places
|elevation=10–1600 m
|distribution=B.C.;N.S.;Ont.;P.E.I.;Que.;Ala.;Ark.;Calif.;Colo.;Conn.;Del.;D.C.;Fla.;Ga.;Idaho;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Maine;Mass.;Mich.;Minn.;Miss.;Mo.;Nebr.;N.H.;N.J.;N.Y.;N.C.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;Tenn.;Tex.;Vt.;Va.;Wash.;W.Va.;Wis.;Wyo.;Pacific Islands (Hawaii).
|reference=None
|publication title=Mant.
|publication year=1824
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/8f726806613d60c220dc4493de13607dd3150896/coarse_grained_fna_xml/V23/V23_159.xml
|genus=Eleocharis
|subgenus=Eleocharis subg. Eleocharis
|section=Eleocharis sect. Eleogenus
|series=Eleocharis (sect. Eleogenus) ser. Ovatae
|species=Eleocharis obtusa
}}<!--

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