View source for Trisetum

{{Treatment/ID
|accepted_name=Trisetum
|accepted_authority=Pers.
|publications=
|basionyms=
|synonyms=
|hierarchy=Poaceae;Poaceae subfam. Pooideae;Poaceae tribe Poeae;Trisetum
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Poaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Poaceae subfam. Pooideae]]</div><div class="higher-taxon"><small>tribe</small>[[Poaceae tribe Poeae]]</div><div class="higher-taxon"><small>genus</small>[[Trisetum]]</div></div>
|volume=Volume 24
|mention_page=
|treatment_page=page 744
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>annual or perennial; sometimes rhizomatous, sometimes cespitose. <b>Culms</b> 5-150 cm, glabrous or pubescent, basal branching extravaginal. <b>Sheaths</b> open the entire length or fused at the base; auricles absent; ligules membranous, often erose to lacerate, sometimes ciliolate; blades rolled in the bud. <b>Inflorescences</b> terminal panicles, open and diffuse to dense and spikelike; branches antrorsely scabrous. <b>Spikelets</b> 2.5-12 mm, usually subsessile to pedicellate, rarely sessile, laterally compressed, with 2-5 florets, reduced florets sometimes present distally; rachillas hairy, internodes evident, prolonged beyond the base of the distal bisexual florets; disarticulation usually initially above the glumes and beneath the florets, subsequently below the glumes, in some species initially below the glumes. <b>Glumes</b> subequal or unequal, keels scabrous, apices usually acute, unawned, often apiculate; lower glumes 1(3)-veined; upper glumes 3(5)-veined, lateral veins less than 1/2 the glume length; calluses hairy; lemmas 3-7-veined, margins hyaline, unawned or awned from above the middle with a single awn, apices usually bifid, sometimes entire; paleas from subequal to longer than the lemmas, membranous, 2-veined, veins usually extending as bristlelike tips; lodicules 2, shallowly and usually slenderly lobed to fimbriate; anthers 3; ovaries glabrous or pubescent; styles 2. <b>Caryopses</b> shorter than the lemmas, concealed at maturity, elongate-fusiform, compressed, brown; embryos elliptic, to 1/3 the length of the caryopses; endosperm milky, x = 7.</span><!--

-->{{Treatment/Body
|distribution=Conn.;Mass.;Maine;N.H.;Vt.;Wash.;Colo.;N.J.;Wis.;Pacific Islands (Hawaii);Wyo.;N.Mex.;Tex.;La.;N.C.;Alta.;B.C.;Greenland;Man.;N.B.;Nfld. and Labr.;N.S.;N.W.T.;Nunavut;Ont.;Que.;Sask.;Yukon;Tenn.;N.Y.;Pa.;Okla.;S.Dak.;Calif.;Nev.;Va.;Alaska;Ariz.;Idaho;Utah;Mo.;Minn.;Mich.;R.I.;Kans.;Mont.;Miss.;Oreg.
|discussion=<p><i>Trisetum</i>, a genus of approximately 75 species, occurs primarily in temperate, subarctic, and alpine regions. Eight species are native to the Flora region; two have been introduced, one of which is not known to have persisted. <i>Trisetum</i> usually differs from <i>Sphenopholis</i> in having longer awns that are inserted lower on the lemmas, and spikelets that disarticulate above the glumes. It differs from <i>Deschampsia</i> primarily in its more acute, bifid lemmas. In addition, all species of <i>Trisetum</i> have awns that are inserted at or above the midpoint of the lemmas; in <i>Deschampsia</i>, the awns are usually inserted at or below midlength, often near the base.</p><!--
--><p><i>Trisetum spicatum</i> is important as forage on native rangelands. Like other species of the genus, it is a significant component of natural food pyramids, especially in arctic and alpine regions and mountain parks. <i>Trisetum flavescens</i> was introduced from Europe as a pasture grass; <i>T. interruptum</i> is often weedy.</p><!--
--><p>Spikelet measurements do not include the awns.</p>
|tables=
|references={{Treatment/Reference
|id=dixon1995a
|text=Dixon, J.M. 1995. Trisetum flavescens (L.) Beauv. (T. pratense Pers., Avena flavescens L.). J. Ecol. 83:895-909
}}{{Treatment/Reference
|id=hitchcock1951a
|text=Hitchcock, A.S. 1951. Manual of the Grasses of the United States, ed. 2, rev. A. Chase. U.S.D.A. Miscellaneous Publication No. 200. U.S. Government Printing Office, Washington, D.C., U.S.A. 1051 pp.
}}{{Treatment/Reference
|id=hulten1959b
|text=Hulten, E. 1959. The Trisetum spicatum complex. Svensk. Bot. Tidskr. 53:203-228
}}{{Treatment/Reference
|id=knot2004a
|text=Knot, V.L., RM. Peterson, R.J. Soreng, and F.O. Zuloaga. 2004. A revision of Trisetum, Peyritschia, and Sphenopholis (Poaceae: Pooideae: Aveninae) in Mexico and Central America. Ann. Missouri Bot. Gard. 91:1-30
}}{{Treatment/Reference
|id=louis-marie1928a
|text=Louis-Marie, Father, O.C. 1928. The genus Trisetum in America. Rhodora 30:209-228, 231-245
}}{{Treatment/Reference
|id=shelly1987a
|text=Shelly, J.S. 1987. Rediscovery and preliminary studies of Trisetum orthochaetum, Missoula County, Montana. Proc. Montana Acad. Sci. 47:3-4 [abstract].
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Plants annual; without sterile shoots.
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Lower glumes 3-veined; spikelets 3-6 mm long; panicles 0.3-1.5 cm wide; plants native
|[[Trisetum interruptum|Trisetum interruptum]]
|-id=key-0-2
|2
|Lower glumes 1-veined; spikelets 2.5-3.5 mm long; panicles 0.5-3 cm wide; plants not native, not established
|[[Trisetum aureum|Trisetum aureum]]
|-id=key-0-1
|1
|Plants perennial; usually producing both fertile and sterile shoots.
|[[#key-0-3| > 3]]
|-id=key-0-3
|3
|Lemmas unawned or with inconspicuous straight awns up to 2 mm long that rarely exceed the lemma apices.
|[[#key-0-4| > 4]]
|-id=key-0-4
|4
|Panicles usually 2-4 cm wide, lax and nodding; callus and rachilla hairs 1.3-2 mm long; plants of eastern North America
|[[Trisetum melicoides|Trisetum melicoides]]
|-id=key-0-4
|4
|Panicles usually 1-1.5 cm wide, erect; callus hairs shorter than 0.5 mm; rachilla hairs up to 1 mm long; plants of western North America
|[[Trisetum wolfii|Trisetum wolfii]]
|-id=key-0-3
|3
|Lemmas with evident awns 3-14 mm long, these straight, curved, flexuous, or geniculate, exceeding the lemma apices.
|[[#key-0-5| > 5]]
|-id=key-0-5
|5
|Plants rhizomatous; culms usually solitary.
|[[#key-0-6| > 6]]
|-id=key-0-6
|6
|Lemma teeth usually 3-6 mm long; ligules 0.5-1(2) mm long
|[[Trisetum flavescens|Trisetum flavescens]]
|-id=key-0-6
|6
|Lemma teeth usually shorter than 1 mm; ligules 1-5 mm long.
|[[#key-0-7| > 7]]
|-id=key-0-7
|7
|Culms 15-65 cm tall; panicles 2-12(16) cm long; plants of Alaska and the Yukon Territory
|[[Trisetum sibiricum|Trisetum sibiricum]]
|-id=key-0-7
|7
|Culms 80-110 cm tall; panicles 13-20 cm long; known only from Montana
|[[Trisetum orthochaetum|Trisetum orthochaetum]]
|-id=key-0-5
|5
|Plants not rhizomatous; culms clumped.
|[[#key-0-8| > 8]]
|-id=key-0-8
|8
|Glumes usually subequal; both glumes lanceolate; upper glumes less than twice as wide as the lower glumes
|[[Trisetum spicatum|Trisetum spicatum]]
|-id=key-0-8
|8
|Glumes usually unequal, sometimes subequal; lower glumes subulate to linear-lanceolate or lance-elliptic; upper glumes broadly lanceolate to ovate or obovate, at least twice as wide as the lower glumes.
|[[#key-0-9| > 9]]
|-id=key-0-9
|9
|Upper glumes as long as or longer than the lowest florets; awns 3-9 mm long; rachilla hairs up to 1.5 mm long; ligules 0.5-2 mm long; panicles yellowish brown
|[[Trisetum flavescens|Trisetum flavescens]]
|-id=key-0-9
|9
|Upper glumes shorter than the lowest florets; awns 7-14 mm long; rachilla hairs 0.7-2.5 mm long; ligules 1.5-6 mm long; panicles green or tan.
|[[#key-0-10| > 10]]
|-id=key-0-10
|10
|Most panicle branches, except sometimes the lowermost, spikelet-bearing for their full length; panicles erect or nodding at the apices; branches ascending to somewhat divergent; upper glumes widest at or below the middle, tapering to the apices; lower glumes 3-5 mm long
|[[Trisetum canescens|Trisetum canescens]]
|-id=key-0-10
|10
|Most panicle branches, except sometimes the uppermost, spikelet-bearing only towards the apices; panicles nodding; branches of at least the lowest 1-3 whorls spreading or drooping; upper glumes widest at or above the middle, rounded to the apices; lower glumes 0.75-3 mm long
|[[Trisetum cernuum|Trisetum cernuum]]
|}
</div></div><!--

-->{{#Taxon:
name=Trisetum
|author=John H. Rumely;
|authority=Pers.
|rank=genus
|parent rank=tribe
|synonyms=
|basionyms=
|family=Poaceae
|distribution=Conn.;Mass.;Maine;N.H.;Vt.;Wash.;Colo.;N.J.;Wis.;Pacific Islands (Hawaii);Wyo.;N.Mex.;Tex.;La.;N.C.;Alta.;B.C.;Greenland;Man.;N.B.;Nfld. and Labr.;N.S.;N.W.T.;Nunavut;Ont.;Que.;Sask.;Yukon;Tenn.;N.Y.;Pa.;Okla.;S.Dak.;Calif.;Nev.;Va.;Alaska;Ariz.;Idaho;Utah;Mo.;Minn.;Mich.;R.I.;Kans.;Mont.;Miss.;Oreg.
|reference=dixon1995a;hitchcock1951a;hulten1959b;knot2004a;louis-marie1928a;shelly1987a
|publication title=
|publication year=
|special status=
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/200273ad09963decb8fc72550212de541d86569d/coarse_grained_fna_xml/V24/V24_1055.xml
|subfamily=Poaceae subfam. Pooideae
|tribe=Poaceae tribe Poeae
|genus=Trisetum
}}<!--

-->[[Category:Treatment]][[Category:Poaceae tribe Poeae]]