View source for Schoenoplectus americanus

{{Treatment/ID
|accepted_name=Schoenoplectus americanus
|accepted_authority=(Persoon) Volkart ex Schinz & R. Keller
|publications={{Treatment/Publication
|title=Fl. Schweiz ed.
|place=2, 1: 75. 1905
|year=1905
}}
|common_names=Olney’s three-square bulrush
|special_status={{Treatment/ID/Special_status
|code=W2
|label=
}}{{Treatment/ID/Special_status
|code=W1
|label=
}}{{Treatment/ID/Special_status
|code=F
|label=Illustrated
}}
|basionyms={{Treatment/ID/Basionym
|name=Scirpus americanus
|authority=Persoon
|rank=species
|publication_title=Syn. Pl.
|publication_place=1: 68. 1805
}}
|synonyms={{Treatment/ID/Synonym
|name=Scirpus olneyi
|authority=A. Gray
|rank=species
}}
|hierarchy=Cyperaceae;Schoenoplectus;Schoenoplectus sect. Schoenoplectus;Schoenoplectus americanus
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Cyperaceae]]</div><div class="higher-taxon"><small>genus</small>[[Schoenoplectus]]</div><div class="higher-taxon"><small>section</small>[[Schoenoplectus sect. Schoenoplectus]]</div><div class="higher-taxon"><small>species</small>[[Schoenoplectus americanus]]</div></div>
|volume=Volume 23
|mention_page=page 46, 51, 53
|treatment_page=page 52
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Rhizomes </b>2–5 mm diam. <b>Culms</b> sharply trigonous, sides deeply concave throughout to rarely nearly flat, 0.4–2.5 m × 3–10 mm. <b>Leaves</b> ca. 3, basal, less than 1/2 culm length; sheath fronts not pinnate-fibrillose; blades 1–3, V-shaped near base, otherwise laterally flattened-trigonous in cross section; distal blade 0.2–1.5 times as long as sheath, 25–200 × 2–8 mm. <b>Inflorescences</b> capitate or very rarely with 1 branch to 5 mm; proximal bract usually erect, resembling leaf blade, 1–6 cm. <b>Spikelets</b> 2–20, 5–15 × 3–5 mm; scales bright orange- to red- or purple-brown to straw-colored, often partly translucent, usually clearly lineolate-spotted, broadly ovate, 2.7–4 × 2–3 mm, smooth or awn sparsely spinulose, margins deciduously ciliolate, flanks of proximal scale often with several ribs, apex rounded to acute, notch 0.1–0.4 mm deep, awn not contorted, 0.2–0.6 mm. <b>Flowers</b>: perianth members (2–)5–6(–7), yellow-brown, bristlelike, slender to stout, often unequal to equaling 1/2 achene body, retrorsely spinulose; anthers 1.5–3 mm; styles 2-fid or 2-fid and 3-fid. <b>Achenes</b> brown when ripe, thickly plano-convex or unequally biconvex or compressed obtusely trigonous, obovoid, 1.8–2.8 × 1.3–2 mm; beak 0.1–0.3 mm. <b>2n</b> = 78.</span><!--

-->{{Treatment/Body
|phenology=Fruiting spring–summer (south), summer (north).
|habitat=Brackish or mineral-rich shores, marshes, fens
|elevation=0–2200 m
|distribution=B.C.;N.S.;Ala.;Ariz.;Calif.;Conn.;Del.;Fla.;Ga.;Idaho;Kans.;La.;Maine;Md.;Mass.;Mich.;Miss.;Mo.;Nev.;N.H.;N.J.;N.Mex.;N.Y.;N.C.;Okla.;Oreg.;R.I.;S.C.;Tex.;Utah;Vt.;Va.;Wash.;Wyo.;Mexico;West Indies (Puerto Rico);Central America;South America.
|discussion=<p>The secondary involucral bracts of <i>Schoenoplectus americanus</i> lack blades and closely resemble floral scales, in contrast to <i>S. pungens</i> and <i>S. deltarum</i>. Although mostly very locally distributed, <i>S. americanus</i> is ecologically important in many coastal marshes. In recent years it has seriously declined (e.g., in Maryland and Louisiana). It may occur in southwestern Kansas; I have not seen a specimen. It probably has been extirpated from the Missouri station, based on one collection from 1886 (G. Yatskievych, pers. comm.). The report from New Hampshire is based on M. L. Fernald (1950). The stations on the Maine and Connecticut coasts, at Lake Champlain in Vermont, and in Oklahoma are based on putative <i>S. americanus</i> × <i>S. pungens</i> specimens. Some plants in the southwest are atypical in having nearly flat culm sides and leaf blades to 1.5 times as long as their sheaths as in the type of <i>Scirpus</i> monophyllus J. Presl & C. Presl from Peru. The name Scirpes americanus was long misapplied to <i>Schoenoplectus pungens</i>; <i>Schoenoplectus americanus</i> was known as <i>Scirpus</i> olneyi (A. E. Schuyler 1974).</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Schoenoplectus americanus
|authority=(Persoon) Volkart ex Schinz & R. Keller
|rank=species
|parent rank=section
|synonyms=Scirpus olneyi
|basionyms=Scirpus americanus
|family=Cyperaceae
|phenology=Fruiting spring–summer (south), summer (north).
|habitat=Brackish or mineral-rich shores, marshes, fens
|elevation=0–2200 m
|distribution=B.C.;N.S.;Ala.;Ariz.;Calif.;Conn.;Del.;Fla.;Ga.;Idaho;Kans.;La.;Maine;Md.;Mass.;Mich.;Miss.;Mo.;Nev.;N.H.;N.J.;N.Mex.;N.Y.;N.C.;Okla.;Oreg.;R.I.;S.C.;Tex.;Utah;Vt.;Va.;Wash.;Wyo.;Mexico;West Indies (Puerto Rico);Central America;South America.
|reference=None
|publication title=Fl. Schweiz ed.
|publication year=1905
|special status=W2;W1;Illustrated
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V23/V23_73.xml
|genus=Schoenoplectus
|section=Schoenoplectus sect. Schoenoplectus
|species=Schoenoplectus americanus
}}<!--

-->[[Category:Treatment]][[Category:Schoenoplectus sect. Schoenoplectus]]