View source for Agropyron

{{Treatment/ID
|accepted_name=Agropyron
|accepted_authority=Gaertn.
|publications=
|basionyms=
|synonyms=
|hierarchy=Poaceae;Poaceae subfam. Pooideae;Poaceae tribe Triticeae;Agropyron
|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 Triticeae]]</div><div class="higher-taxon"><small>genus</small>[[Agropyron]]</div></div>
|volume=Volume 24
|mention_page=
|treatment_page=page 277
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>perennial; densely to loosely cespitose, sometimes rhizomatous. <b>Culms</b> 25-110 cm, geniculate or erect. <b>Sheaths</b> open; auricles usually present; ligules membranous, often erose. <b>Inflorescences</b> spikes, usually pectinate; middle internodes 0.2-3(5.5) mm, basal internodes often somewhat longer. <b>Spikelets</b> solitary, usually more than 3 times as long as the internodes, usually divergent or spreading from the rachis, with 3-16 florets; disarticulation above the glumes and beneath the florets. <b>Glumes</b> shorter than the adjacent lemmas, lance-ovate to lanceolate, 1-5-veined, asymmetrically keeled, a secondary keel sometimes present on the wider side, keels glabrous or with hairs, hairs not tufted, apices acute and entire, sometimes awned, awns to 6 mm; lemmas 5-7-veined, asymmetrically keeled, acute to awned, awns to 4.5 mm; paleas from slightly shorter than to exceeding the lemmas, bifid; anthers 3, 3-5 mm, yellow. <b>Caryopses</b> usually falling with the lemmas and paleas attached, x = 7. <b>Haplome</b> P.</span><!--

-->{{Treatment/Body
|distribution=Wash.;Del.;Wis.;Idaho;Mont.;Oreg.;Wyo.;Kans.;N.Dak.;Nebr.;N.Mex.;Okla.;S.Dak.;N.H.;Ariz.;Tex.;Conn.;N.Y.;Calif.;Nev.;Colo.;Alaska;Ill.;Ind.;Iowa;Utah;Mass.;Ohio;Mo.;Minn.;Mich.;Alta.;B.C.;Nfld. and Labr. (Nfld.);Man.;N.S.;N.W.T.;Ont.;Que.;Sask.;Yukon;Ky.
|discussion=<p><i>Agropyron</i>, it is now agreed, should be restricted to perennial species of Triticeae with keeled glumes, i.e., <i>A. cristatum</i> and its allies, or the "crested wheatgrasses". The excluded species are distributed among <i>Pseudoroegneria</i>, <i>Thinopyrum</i>, <i>Elymus</i>, <i>Eremopyrum</i>, and <i>Pascopyrum</i>. This leaves <i>Agropyron</i> as a Eurasian genus that includes diploid, tetraploid, and hexaploid plants, all of which contain a single genome, designated the P genome by the International Triticeae Consortium. The genus is now widespread in western North America, frequently being used for soil stabilization on degraded rangeland and abandoned cropland, because it is highly tolerant of grazing and provides good spring forage.</p><!--
--><p>Prior to the 1930s, most Soviet agrostologists recognized two species in the genus: <i>Agropyron cristatum</i>, with broad spikes; and <i>A. desertorum</i> (Fischer ex Link) Schult., with narrow spikes. Kosarev (1949) recognized four species, the two additional species being A. pectiniforme Roem. & Schult. and A. sibiricwn (Willd.) P. Beauv. Tsvelev (1976) recognized 10 species, within one of which, <i>A. cristatum</i>, he recognized nine subspecies. He considered the widely distributed taxon introduced to many different countries to be <i>A. cristatum</i> subsp. pectinatum (M. Bieb.) Tzvelev. Chen and Zhu (2006) suggested that there are 15 species in the world, five of which are present in China.</p><!--
--><p>Estimating the number of species present in the Flora region is difficult, because many seed samples were brought into the region, planted out in experimental plots, and subsequently developed for various agricultural uses. In reviewing the history of crested wheatgrass in North America, Dillman (1946) stated that, based on the identifications provided with some of the early seed accessions, two species of crested wheatgrass had been introduced into North America, <i>Agropyron cristatum</i> and <i>A. desertorum</i>. He described them as "quite distinct, both in seed and plant characters" (p. 248). According to Dewey (1986), a third species, now known as <i>A. fragile</i>, was introduced at about the same time; it apparently escaped Dillman's attention.</p><!--
--><p>The problem is that "taxa introduced into North America soon lose their taxonomic identity and genetic integrity because of extensive intercrossing that occurs in nursery situations" (Dewey 1986, p. 34). Despite his observations, Dewey recognized three species of <i>Agropyron</i> in North America, and admitted that identifying individual plants "will often be difficult and unsatisfying. Variation is continuous between the morphological extremes of the unawned, linear-spiked <i>A. fragile</i> to the broad, pectinate-spiked <i>A. cristatum</i>'" (p. 38).</p><!--
--><p>This treatment recognizes two species within the Flora region, a very broadly interpreted <i>Agropyron cristatum</i>, which includes Dewey's <i>A. cristatum</i> and <i>A. desertorum</i>, and a traditionally interpreted <i>A. fragile</i>. <i>Agropyron cristatum</i> in North America reflects a process that might be called despeciation.</p>
|tables=
|references={{Treatment/Reference
|id=asay1979a
|text=Asay, K.H. and D.R. Dewey. 1979. Bridging ploidy differences in crested wheatgrass with hexaploid x diploid hybrids. Crop Science 19:519-523
}}{{Treatment/Reference
|id=asay1992a
|text=Asay, K.H., K.B. Jensen, C. Hsiao, and D.R. Dewey. 1992. Probable origin of standard crested wheatgrass, Agropyron desertorum (Fisch. ex Link) Schultes. Canad. J. PI. Sci. 72:763-772
}}{{Treatment/Reference
|id=chen2006b
|text=Chen, S.-L. and G.-H. Zhu. 2006. Agropyron. Pp. 439-441 in Z.-Y. Wu, P.H. Raven, and D.-Y. Hong (eds.). Flora of China, vol. 22 (Poaceae). Science Press, Beijing, Peoples Republic of China and Missouri Botanical Garden Press, St. Louis, Missouri, U.S.A. 653 pp. http://flora.huh.harvard.edu/china/mss/volume22/index.htm
}}{{Treatment/Reference
|id=dewey1986a
|text=Dewey, D.R. 1986. Taxonomy of the crested wheatgrasses (Agropyron). Pp. 31-42 in K.L. Johnson (ed.). Crested Wheatgrass: Its Values, Problems and Myths; Symposium Proceedings. Utah State University, Logan, Utah, U.S.A. 348 pp.
}}{{Treatment/Reference
|id=dillman1946a
|text=Dillman, A.C. 1946. The beginnings of crested wheatgrass in North America. J. Amer. Soc. Agron. 38:237-250
}}{{Treatment/Reference
|id=kosarev1949a
|text=Kosarev, M.G. 1949. The variability of characters of crested wheatgrass. Selekts. & Semenov. 4:41-43
}}{{Treatment/Reference
|id=lesica1996a
|text=Lesica, P. and T.H. DeLuca. 1996. Long-term harmful effects of crested wheatgrass on Great Plains grassland ecosystems. J. Soil Water Conservation 51:408-409
}}{{Treatment/Reference
|id=tsvelev1976a
|text=Tsvelev, N.N. 1976. Zlaki SSSR. Nauka, Leningrad [St. Petersburg], Russia. 788 pp.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Lemmas usually awned, awns 1-6 mm long; spikelets diverging from the rachises at angles of 30-95°; spikes narrowly to broadly lanceolate, rectangular, or ovate in outline
|[[Agropyron cristatum|Agropyron cristatum]]
|-id=key-0-1
|1
|Lemmas unawned, sometimes mucronate; spikelets diverging from the rachises at an angle of less than 30(35)°; spikes linear to narrowly lanceolate in outline
|[[Agropyron fragile|Agropyron fragile]]
|}
</div></div><!--

-->{{#Taxon:
name=Agropyron
|author=Mary E. Barkworth;
|authority=Gaertn.
|rank=genus
|parent rank=tribe
|synonyms=
|basionyms=
|family=Poaceae
|illustrator=Cindy Roché
|illustration copyright=Utah State University
|distribution=Wash.;Del.;Wis.;Idaho;Mont.;Oreg.;Wyo.;Kans.;N.Dak.;Nebr.;N.Mex.;Okla.;S.Dak.;N.H.;Ariz.;Tex.;Conn.;N.Y.;Calif.;Nev.;Colo.;Alaska;Ill.;Ind.;Iowa;Utah;Mass.;Ohio;Mo.;Minn.;Mich.;Alta.;B.C.;Nfld. and Labr. (Nfld.);Man.;N.S.;N.W.T.;Ont.;Que.;Sask.;Yukon;Ky.
|reference=asay1979a;asay1992a;chen2006b;dewey1986a;dillman1946a;kosarev1949a;lesica1996a;tsvelev1976a
|publication title=
|publication year=
|special status=
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V24/V24_396.xml
|subfamily=Poaceae subfam. Pooideae
|tribe=Poaceae tribe Triticeae
|genus=Agropyron
}}<!--

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