View source for Poa laxa

{{Treatment/ID
|accepted_name=Poa laxa
|accepted_authority=Haenke
|publications=
|common_names=Lax bluegrass
|basionyms=
|synonyms=
|hierarchy=Poaceae;Poaceae subfam. Pooideae;Poaceae tribe Poeae;Poa;Poa subg. Poa;Poa sect. Oreinos;Poa laxa
|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>[[Poa]]</div><div class="higher-taxon"><small>subgenus</small>[[Poa subg. Poa]]</div><div class="higher-taxon"><small>section</small>[[Poa sect. Oreinos]]</div><div class="higher-taxon"><small>species</small>[[Poa laxa]]</div></div>
|volume=Volume 24
|mention_page=
|treatment_page=page 570
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>perennial; not or only slightly glaucous; densely tufted, not stoloniferous, not rhizomatous. <b>Basal</b> branching mixed, mainly extravaginal or mainly pseudointravaginal, sometimes intravaginal. <b>Culms</b> 8-35 cm tall, 0.5-0.9 mm thick, ascending to erect, slender; nodes terete, 0(1) exserted. <b>Sheaths</b> closed for 1/5-1/3 their length, terete, smooth, glabrous, bases of basal sheaths glabrous; collars smooth or scabrous, glabrous; ligules 2-4 mm, smooth, apices acute, often lacerate; innovation blades similar to the cauline blades; cauline blades 1-2(3) mm wide, flat, thin, soft, smooth, narrowly prow-tipped, blades not strongly graduated or reduced upwards. <b>Panicles</b> 2-8 cm, slightly lax, usually loosely contracted and sparse, infrequently contracted and dense; nodes with 1-3(5) branches; branches 1-3(4) cm, usually ascending or weakly spreading, infrequently erect, fairly straight or flexuous, slender, sulcate or angled, smooth or the angles sparsely scabrous, with 1-8 spikelets. <b>Spikelets</b> 4-6 mm, lengths to 3 times widths, laterally compressed; florets 2-5; rachilla internodes shorter than 1 mm, smooth, glabrous. <b>Glumes</b> nearly equaling or slightly longer than the adjacent lemmas, lanceolate to broadly lanceolate, thin, distinctly keeled, keels smooth or sparsely scabrous; lower glumes 1-3-veined; upper glumes shorter than or subequal to the lowest lemmas; calluses glabrous or webbed, hairs usually shorter than 1/4 the lemma length, sparse; lemmas 3-4.6 mm, lanceolate to broadly lanceolate, thin, distinctly keeled, keels and marginal veins short- to long-villous, lateral veins glabrous or sparsely softly puberulent, lateral veins obscure, intercostal regions glabrous, margins glabrous, apices acute; paleas sparsely scabrous over the keels; anthers (0.6)0.8-1.1(1.3) mm. <b>2n</b> = 28, 42, 84.</span><!--

-->{{Treatment/Body
|distribution=Maine;N.H.;Colo.;N.Y.;Vt.;Mont.;Oreg.;Wyo.;Alta.;B.C.;Nfld. and Labr.;Que.
|discussion=<p><i>Poa laxa</i> is a low arctic to high alpine amphiatlantic species. It has been treated as a series of separate species, but the differences seem relatively minor and incomplete. Its short anthers and smoother branches usually distinguish it from <i>P. glauca</i> (p. 576), with which it can hybridize to form <i>P. laxa</i> x glauca (p. 572).</p><!--
--><p><i>Poa laxa</i> has four subspecies, two of which are native to the Flora region; subsp. laxa grows in central Europe; and subsp. flexuosa (Sm.) Hyl. in northwestern Europe.</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Innovations primarily extravaginal; panicle branches fairly straight; calluses glabrous
|[[Poa laxa subsp. banffiana|Poa laxa subsp. banffiana]]
|-id=key-0-1
|1
|Innovations primarily intravaginal; panicle branches flexuous, usually at least some florets having a webbed callus
|[[Poa laxa subsp. fernaldiana|Poa laxa subsp. fernaldiana]]
|}
</div></div><!--

-->{{#Taxon:
name=Poa laxa
|authority=Haenke
|rank=species
|parent rank=section
|synonyms=
|basionyms=
|family=Poaceae
|illustrator=Sandy Long
|illustration copyright=Utah State University
|distribution=Maine;N.H.;Colo.;N.Y.;Vt.;Mont.;Oreg.;Wyo.;Alta.;B.C.;Nfld. and Labr.;Que.
|reference=None
|publication title=
|publication year=
|special status=
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V24/V24_796.xml
|subfamily=Poaceae subfam. Pooideae
|tribe=Poaceae tribe Poeae
|genus=Poa
|subgenus=Poa subg. Poa
|section=Poa sect. Oreinos
|species=Poa laxa
}}<!--

-->[[Category:Treatment]][[Category:Poa sect. Oreinos]]