View source for Agrostis gigantea

{{Treatment/ID
|accepted_name=Agrostis gigantea
|accepted_authority=Roth
|publications=
|common_names=Redtop;Agrostide blanche
|special_status={{Treatment/ID/Special_status
|code=I
|label=Introduced
}}
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Agrostis stolonifera var. major
|authority=
|rank=variety
}} {{Treatment/ID/Synonym
|name=Agrostis gigantea var. ramosa
|authority=
|rank=variety
}} {{Treatment/ID/Synonym
|name=Agrostis gigantea var. dispar
|authority=
|rank=variety
}} {{Treatment/ID/Synonym
|name=Agrostis alba var. major
|authority=
|rank=variety
}}
|hierarchy=Poaceae;Poaceae subfam. Pooideae;Poaceae tribe Poeae;Agrostis;Agrostis gigantea
|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>[[Agrostis]]</div><div class="higher-taxon"><small>species</small>[[Agrostis gigantea]]</div></div>
|volume=Volume 24
|mention_page=
|treatment_page=page 641
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>perennial; rhizomatous, rhizomes to 25 cm, not stoloniferous. <b>Culms</b> 20-120 cm, erect, sometimes geniculate at the base, sometimes rooting at the lower nodes, with 4-7 nodes. <b>Leaves</b> mostly cauline, sheaths smooth or sparsely scabridulous; ligules longer than wide, dorsal surfaces usually scabrous, sometimes smooth, apices rounded to truncate, erose to lacerate, basal ligules 1-4.5 mm, upper ligules 2-7 mm; blades 4-10 cm long, 3-8 mm wide, flat. <b>Panicles</b> 8-25(30) cm long, less than 1/2 the length of the culm, (1.5)3-15 cm wide, erect, open, broadly ovate, exserted from the upper sheaths at maturity, lowest node with (1)3-8 branches; branches scabrous, spreading during and after anthesis, usually some branches spikelet-bearing to the base, lower branches 4-9 cm, usually with many shorter secondary branches resulting in crowding of the spikelets, spikelets restricted to the distal 1/2 of the branches and not crowded in shade plants; pedicels 0.3-3.4(4.2) mm. <b>Spikelets</b> narrowly ovate to lance¬olate, green and slightly to strongly suffused with purple. <b>Glumes</b> subequal, 1.7-3.2 mm, lanceolate, 1-veined, acute to apiculate; lower glumes scabrous on the distal 1/2 of the midvein; upper glumes scabridulous on the distal 1/2 of the midvein; callus hairs to 0.5 mm, sparse; lemmas 1.5-2.2 mm, opaque to translucent, smooth, 3-5-veined, veins usually obscure, sometimes prominent throughout or distally, often excurrent to 0.2 mm, apices usually acute, sometimes obtuse or truncate, usually unawned, rarely with a 0.4-1.5(3) mm straight awn arising from near the apices to near the base; paleas 0.7-1.4 mm, about Vi the length of the lemmas, veins visible; anthers 3, 1-1.4 mm. <b>Caryopses</b> 1-1.5 mm; endosperm solid. <b>2n</b> = 42.</span><!--

-->{{Treatment/Body
|distribution=Conn.;N.J.;N.Y.;Wash.;Del.;D.C.;Wis.;W.Va.;Mass.;Maine;N.H.;R.I.;Vt.;Wyo.;N.Mex.;Tex.;La.;N.Dak.;Nebr.;Tenn.;Pa.;Okla.;Alaska;Nev.;Va.;Colo.;Calif.;Ala.;Ark.;Ill.;Ga.;Ind.;Iowa;Ariz.;Idaho;Md.;Ohio;Utah;Mo.;Minn.;Mich.;Kans.;Mont.;Miss.;S.C.;Ky.;Oreg.;Alta.;B.C.;Greenland;Man.;N.B.;Nfld. and Labr. (Labr.);N.S.;N.W.T.;Ont.;P.E.I.;Que.;Sask.;Yukon
|discussion=<p><i>Agrostis gigantea</i> grows in fields, roadsides, ditches, and other disturbed habitats, mostly at lower elevations. It is a serious agricultural weed, as well as a valuable soil stabilizer. In the Flora region, its range extends from the subarctic to Mexico; it is considered to be native to Eurasia. It is more heat tolerant than most species of <i>Agrostis</i>.</p><!--
--><p><i>Agrostis gigantea</i> has been confused with <i>A. stolonifera</i> (see next), from which it differs in having rhizomes and a more open panicle. <i>Agrostis stolonifera</i> has elongated leafy stolons, mainly all above the surface, that root at the nodes, and the panicles are condensed and often less strongly pigmented than in <i>A. gigantea</i>. Its distribution tends to be more northern and coastal where ditches and pond margins are common habitats, and its stolons enable it to form loose mats. <i>Agrostis gigantea</i> is ecologically adapted to a more extreme climate—hot summers/cold winters and drought—than <i>A. stolonifera</i>. It is also similar to <i>A. capillaris</i> (p. 639) and <i>A. castellana</i> (p. 639); it differs from both in its longer ligules, from <i>A. capillaris</i> in its less open panicles with spikelets near the base of the branches, and from <i>A. castellana</i> in being more extensively rhizomatous.</p><!--
--><p>When <i>Agrostis gigantea</i> grows in damp hollows under trees it becomes more like <i>A. stolonifera</i>, particularly when the inflorescence is young, not expanded, and pale. If the rootstock is not collected, identification is a major problem.</p>
|tables=
|references=
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-->{{#Taxon:
name=Agrostis gigantea
|authority=Roth
|rank=species
|parent rank=genus
|synonyms=Agrostis stolonifera var. major;Agrostis gigantea var. ramosa;Agrostis gigantea var. dispar;Agrostis alba var. major
|basionyms=
|family=Poaceae
|illustrator=Sandy Long
|illustration copyright=Utah State University
|distribution=Conn.;N.J.;N.Y.;Wash.;Del.;D.C.;Wis.;W.Va.;Mass.;Maine;N.H.;R.I.;Vt.;Wyo.;N.Mex.;Tex.;La.;N.Dak.;Nebr.;Tenn.;Pa.;Okla.;Alaska;Nev.;Va.;Colo.;Calif.;Ala.;Ark.;Ill.;Ga.;Ind.;Iowa;Ariz.;Idaho;Md.;Ohio;Utah;Mo.;Minn.;Mich.;Kans.;Mont.;Miss.;S.C.;Ky.;Oreg.;Alta.;B.C.;Greenland;Man.;N.B.;Nfld. and Labr. (Labr.);N.S.;N.W.T.;Ont.;P.E.I.;Que.;Sask.;Yukon
|reference=None
|publication title=
|publication year=
|special status=Introduced
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/200273ad09963decb8fc72550212de541d86569d/coarse_grained_fna_xml/V24/V24_906.xml
|subfamily=Poaceae subfam. Pooideae
|tribe=Poaceae tribe Poeae
|genus=Agrostis
|species=Agrostis gigantea
}}<!--

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