View source for Nassella

{{Treatment/ID
|accepted_name=Nassella
|accepted_authority=(Trin.) E. Desv.
|publications=
|basionyms=
|synonyms=
|hierarchy=Poaceae;Poaceae subfam. Pooideae;Poaceae tribe Stipeae;Nassella
|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 Stipeae]]</div><div class="higher-taxon"><small>genus</small>[[Nassella]]</div></div>
|volume=Volume 24
|mention_page=
|treatment_page=page 170
}}<!--

--><span class="statement" id="st-d0_s0" data-properties=""><b>Plants </b>usually perennial, rarely annual;</span> <span class="statement" id="st-d0_s1" data-properties="whole_organism duration;whole_organism duration;whole_organism growth form;whole_organism architecture;whole_organism growth form">cespitose, occasionally rhizomatous.</span> <span class="statement" id="st-d0_s2" data-properties="culm atypical some measurement;culm some measurement;culm architecture;branch fragility"><b>Culms </b>10-175 (210) cm, sometimes branched at the upper nodes, branches flexible;</span> <span class="statement" id="st-d0_s3" data-properties="prophyll prominence;prophyll height or length or size">prophylls not evident, shorter than the sheaths.</span> <span class="statement" id="st-d0_s4" data-properties="leaf duration;leaf position"><b>Leaves </b>mostly basal, not overwintering;</span> <span class="statement" id="st-d0_s5" data-properties="sheath architecture">sheaths open;</span> <span class="statement" id="st-d0_s6" data-properties="cleistogene presence">cleistogenes sometimes present;</span> <span class="statement" id="st-d0_s7" data-properties="auricle presence">auricles absent;</span> <span class="statement" id="st-d0_s8" data-properties="ligule texture;ligule pubescence;ligule pubescence">ligules membranous, sometimes pubescent or ciliate;</span> <span class="statement" id="st-d0_s9" data-properties="leaf blade length;leaf blade width;apex shape;apex shape;blade-leaf distance">blades of basal leaves 3-60 cm long, 0.2-8 mm wide, apices narrowly acute to acute, not sharp, flag leaf-blades 1-80 mm, bases about as wide as the top of the sheaths.</span> <span class="statement" id="st-d0_s10" data-properties="inflorescence position"><b>Inflorescences </b>terminal panicles, sometimes partially included at maturity.</span> <span class="statement" id="st-d0_s11" data-properties="spikelet some measurement;floret quantity"><b>Spikelets </b>3-22 mm, with 1 floret;</span> <span class="statement" id="st-d0_s12" data-properties="">rachillas not prolonged beyond the base of the floret;</span> <span class="statement" id="st-d0_s13" data-properties="rachilla length">disarticulation above the glumes, beneath the floret.</span> <span class="statement" id="st-d0_s14" data-properties="glume length or size;glume shape;glume shape;basal portion coloration;basal portion coloration;basal portion architecture;basal portion architecture or shape"><b>Glumes </b>longer than the floret, narrowly lanceolate or ovate, basal portion usually purplish at anthesis, color fading with age, (1) 3-5-veined, sometimes awned;</span> <span class="statement" id="st-d0_s15" data-properties="floret shape;floret shape">florets usually terete, sometimes slightly laterally compressed;</span> <span class="statement" id="st-d0_s16" data-properties="callus shape;callus shape;callus pubescence;callus pubescence">calluses blunt or sharp, glabrous or antrorsely strigose;</span> <span class="statement" id="st-d0_s17" data-properties="lemma relief;lemma relief;lemma architecture or pubescence or relief;lemma pubescence;lemma pubescence;lemma arrangement or shape;apex shape;apex fusion;apex prominence;base coloration;base size">lemmas usually papillose or tuberculate, at least distally, sometimes smooth throughout, glabrous or variously hairy, strongly convolute, wrapping 1.2-1.5 times around the caryopses, apices not lobed, fused distally into crowns, these often evident by their pale color and constricted bases;</span> <span class="statement" id="st-d0_s18" data-properties="crown pubescence;base architecture">crowns mostly glabrous, rims often bearing hairs with bulbous bases;</span> <span class="statement" id="st-d0_s19" data-properties="awn position or structure subtype;awn position;awn duration;awn duration;awn size or quantity;awn size or quantity">awns terminal, centric or eccentric, deciduous or persistent, usually twice-geniculate, second geniculation often obscure;</span> <span class="statement" id="st-d0_s20" data-properties="palea quantity;palea pubescence;palea prominence or shape">paleas up to 1/2 as long as the lemmas, glabrous, without veins, flat;</span> <span class="statement" id="st-d0_s21" data-properties="lodicule quantity;lodicule quantity;lodicule quantity;lodicule quantity">lodicules 2 or 3, if 3, the third somewhat shorter than the other 2;</span> <span class="statement" id="st-d0_s22" data-properties="anther quantity;anther quantity;anther quantity;anther shape">anthers 1 or 3, if 3, often of 2 lengths, penicillate;</span> <span class="statement" id="st-d0_s23" data-properties="ovary pubescence">ovaries glabrous;</span> <span class="statement" id="st-d0_s24" data-properties="style quantity;base fusion">styles 2, bases free.</span> <span class="statement" id="st-d0_s25" data-properties="caryopse pubescence;caryopse architecture or shape"><b>Caryopses </b>glabrous, not ribbed;</span> <span class="statement" id="st-d0_s26" data-properties="hilum shape">hila elongate;</span> <span class="statement" id="st-d0_s27" data-properties="">embryos to 2/5 as long as the caryopses.</span> <span class="statement" id="st-d0_s28" data-properties="embryo quantity;x chromosome quantity;x chromosome quantity">x = 7, 8.</span><!--

-->{{Treatment/Body
|distribution=Wis.;Pacific Islands (Hawaii);Kans.;N.Dak.;Nebr.;S.Dak.;Wyo.;N.Mex.;Tex.;La.;N.Y.;Ill.;Ky.;N.C.;S.C.;Alta.;B.C.;Man.;N.W.T.;Sask.;Yukon;Colo.;Calif.;Ala.;Ark.;Iowa;Ariz.;Idaho;Okla.;Utah;Minn.;Mont.;Oreg.
|discussion=<p>Nassella used to be interpreted as a South American genus of approximately 14 species. It is now interpreted as including at least 116 species (Barkworth and Torres 2001), the majority of which are South American. The additional species were previously included in Stipa. There are eight species in the Flora region, one of which is introduced; two additional species treated here were found in the region at one time, but have not become established. The strongly convolute lemmas distinguish Nassella from all other genera of Stipeae in the Americas and, in combination with the reduced, ecostate, glabrous paleas, from all other genera in the tribe worldwide. Molecular data (Jacobs et al. 2006) support the expanded interpretation of Nassella. Relationships among the species have not been explored.</p><!--
--><p>Many species of Nassella develop both cleistogamous and chasmogamous florets in the terminal panicle. The cleistogamous florets have 1-3 anthers that are less than 1 mm long; the chasmogamous florets have 3 anthers that are significantly longer. In addition, some species develop panicles in the axils of their basal sheaths. Spikelets of cleistogenes have reduced or no glumes, and florets with no or very short awns.</p>
|tables=
|references={{Treatment/Reference
|id=barkworth1990a
|text=Barkworth, M.E. 1990. Nassella (Gramineae: Stipeae): Revised interpretation and nomenclatural changes. Taxon 39:597-614
}}{{Treatment/Reference
|id=barkworth1993c
|text=Barkworth, M.E. 1993. Nassella. Pp. 1274-1276 in J.C. Hickman (ed.). The Jepson Manual: Higher Plants of California. University of California Press, Berkeley and Los Angeles, California, U.S.A. 1400 pp.
}}{{Treatment/Reference
|id=barkworth2001a
|text=Barkworth, M.E. and M.A. Torres. 2001. Distribution and diagnostic characters of Nassella (Poaceae: Stipeae). Taxon 50:439-468
}}{{Treatment/Reference
|id=brown1952a
|text=Brown, W.V. 1952. The relation of soil moisture to cleistogamy in Stipa leucotricha. Bot. Gaz. 113:438-444
}}{{Treatment/Reference
|id=desvaux1854a
|text=Desvaux, E. 1854. Gramineas. Pp. 233-469 in C. Gay. Flora Chilena [Historia Fisica y Politica de Chile], vol. 6. Museo Historia Natural, Santiago, Chile. 551 pp. [1853 on title page printed March 1854]
}}{{Treatment/Reference
|id=dyksterhuis1949a
|text=Dyksterhuis, E.J. 1949. Axillary cleistogenes in Stipa leucotricha and their role in nature. Ecology 26:195-199
}}{{Treatment/Reference
|id=hamilton1997a
|text=Hamilton, J.G. 1997. Changing perceptions of pre-European grasslands in California. Madrono 44:311-333
}}{{Treatment/Reference
|id=jacobs1995a
|text=Jacobs, S.W.L., J. Everett, and M.E. Barkworth. 1995. Clarification of morphological terms used in the Stipeae (Gramineae), and a reassessment of Nassella in Australia. Taxon 44:33-41
}}{{Treatment/Reference
|id=jacobs2006a
|text=Jacobs, S.W.L., R. Bayer, J. Everett, M.O. Arriaga, M.E. Barkworth, A. Sabin-Badereau, M.A. Torres, F. Vazquez, and N. Bagnall. 2006. Systematics of the tribe Stipeae using molecular data. Aliso 23:349-361
}}{{Treatment/Reference
|id=love1946a
|text=Love, R.M. 1946. Interspecific hybridization in Stipa: I. Natural hybrids. Amer. Naturalist 80:189-192
}}{{Treatment/Reference
|id=love1954a
|text=Love, R.M. 1954. Interspecific hybridization in Stipa: II. Hybrids of S. cemua, S. lepida, and S. pulchra. Amer. J. Bot. 41:107-110.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Florets 1.5-3 mm long; blades 0.2-1.5 mm wide, usually tightly convolute.
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Florets widest about midlength; awns 45-100 mm long, almost centric
|[[Nassella tenuissima|Nassella tenuissima]]
|-id=key-0-2
|2
|Florets widest near the top; awns 7-35 mm long, eccentric.
|[[#key-0-3| > 3]]
|-id=key-0-3
|3
|Awns 15-35 mm long; lemmas strongly tuberculate, particularly distally
|[[Nassella trichotoma|Nassella trichotoma]]
|-id=key-0-3
|3
|Awns 7-10 mm long; lemmas smooth
|[[Nassella chilensis|Nassella chilensis]]
|-id=key-0-1
|1
|Florets 3.4-13 mm long; blades 0.4-8 mm wide, flat to convolute.
|[[#key-0-2| > 2]]
|-id=key-0-4
|4
|Terminal segment of the awns cernuous.
|[[#key-0-5| > 5]]
|-id=key-0-5
|5
|Awns 12-55 mm long, 0.1-0.2 mm thick at the base
|[[Nassella lepida|Nassella lepida]]
|-id=key-0-5
|5
|Awns 50-110 mm long, 0.2-0.3 mm thick at the base
|[[Nassella cemua|Nassella cemua]]
|-id=key-0-4
|4
|Terminal segment of the awns straight.
|[[#key-0-5| > 5]]
|-id=key-0-6
|6
|Florets 3.4-5.5 mm long; lemmas not constricted below the crown; awns 19-32 mm long
|[[Nassella viridula|Nassella viridula]]
|-id=key-0-6
|6
|Florets 6-13 mm long; lemmas constricted below the crown; awns 30-120 mm long.
|[[#key-0-7| > 7]]
|-id=key-0-7
|7
|Lemmas hairy between the veins at maturity
|[[Nassella pulchra|Nassella pulchra]]
|-id=key-0-7
|7
|Lemmas glabrous between the veins at maturity.
|[[#key-0-8| > 8]]
|-id=key-0-8
|8
|Crowns usually wider than long, the rims with hairs to 0.5 mm long; florets widest just below the crowns
|[[Nassella neesiana|Nassella neesiana]]
|-id=key-0-8
|8
|Crowns usually longer than wide, the rims with hairs 1-2 mm long; florets widest near or slightly above midlength. 9. Florets 6.5-13 mm long; crowns often flaring distally; plants native to Texas and adjacent states
|[[Nassella leucotricha|Nassella leucotricha]]
|-id=key-0-9
|9
|Florets 6-8 mm long; crowns more or less straight-sided; plants introduced, established in California
|[[Nassella manicata|Nassella manicata]]
|}
</div></div><!--

-->{{#Taxon:
name=Nassella
|author=Mary E. Barkworth;
|authority=(Trin.) E. Desv.
|rank=genus
|parent rank=tribe
|synonyms=
|basionyms=
|family=Poaceae
|distribution=Wis.;Pacific Islands (Hawaii);Kans.;N.Dak.;Nebr.;S.Dak.;Wyo.;N.Mex.;Tex.;La.;N.Y.;Ill.;Ky.;N.C.;S.C.;Alta.;B.C.;Man.;N.W.T.;Sask.;Yukon;Colo.;Calif.;Ala.;Ark.;Iowa;Ariz.;Idaho;Okla.;Utah;Minn.;Mont.;Oreg.
|reference=barkworth1990a;barkworth1993c;barkworth2001a;brown1952a;desvaux1854a;dyksterhuis1949a;hamilton1997a;jacobs1995a;jacobs2006a;love1946a;love1954a
|publication title=
|publication year=
|special status=
|source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V24/V24_234.xml
|subfamily=Poaceae subfam. Pooideae
|tribe=Poaceae tribe Stipeae
|genus=Nassella
|anther quantity=3;3;1
|anther shape=penicillate
|apex fusion=fused
|apex prominence=evident
|apex shape=not lobed;not sharp;narrowly acute;acute
|auricle presence=absent
|awn duration=persistent;deciduous
|awn position=eccentric
|awn position or structure subtype=terminal
|awn size or quantity=2 times-geniculate second geniculation often obscure;2 times-geniculate second geniculation often obscure
|basal portion architecture=(1)3-5-veined
|basal portion architecture or shape=awned
|basal portion coloration=color fading;purplish
|base architecture=bulbous
|base coloration=pale color
|base fusion=free
|base size=constricted
|blade-leaf distance=1mm;80mm
|branch fragility=pliable
|callus pubescence=strigose;glabrous
|callus shape=sharp;blunt
|caryopse architecture or shape=not ribbed
|caryopse pubescence=glabrous
|cleistogene presence=absent
|crown pubescence=glabrous
|culm architecture=branched
|culm atypical some measurement=210
|culm some measurement=10cm;175cm
|embryo quantity=0;2/5
|floret quantity=1
|floret shape=compressed;terete
|glume length or size=longer
|glume shape=ovate;lanceolate
|hilum shape=elongate
|inflorescence position=included
|leaf blade length=3cm;60cm
|leaf blade width=0.2mm;8mm
|leaf duration=not overwintering
|leaf position=basal
|lemma architecture or pubescence or relief=smooth
|lemma arrangement or shape=convolute
|lemma pubescence=hairy;glabrous
|lemma relief=tuberculate;papillose
|ligule pubescence=ciliate;pubescent
|ligule texture=membranous
|lodicule quantity=2;3;3;2
|ovary pubescence=glabrous
|palea prominence or shape=flat
|palea pubescence=glabrous
|palea quantity=0;1/2
|prophyll height or length or size=shorter
|prophyll prominence=not evident
|rachilla length=not prolonged
|sheath architecture=open
|spikelet some measurement=3mm;22mm
|style quantity=2
|whole_organism architecture=rhizomatous
|whole_organism duration=annual;perennial
|whole_organism growth form=plant;cespitose
|x chromosome quantity=8;7
}}<!--

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