View source for Helenium flexuosum

{{Treatment/ID
|accepted_name=Helenium flexuosum
|accepted_authority=Rafinesque
|publications={{Treatment/Publication
|title=New Fl.
|place=4: 81. 1838
|year=1838
}}
|common_names=Purplehead sneezeweed;hélénie nudiflore
|special_status={{Treatment/ID/Special_status
|code=E
|label=Endemic
}}
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Helenium nudiflorum
|authority=Nuttall
|rank=species
}}
|hierarchy=Asteraceae;Asteraceae tribe Heliantheae;Asteraceae (tribe Heliantheae) subtribe Gaillardiinae;Helenium;Helenium flexuosum
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Heliantheae]]</div><div class="higher-taxon"><small>subtribe</small>[[Asteraceae (tribe Heliantheae) subtribe Gaillardiinae]]</div><div class="higher-taxon"><small>genus</small>[[Helenium]]</div><div class="higher-taxon"><small>species</small>[[Helenium flexuosum]]</div></div>
|volume=Volume 21
|mention_page=page 427, 430
|treatment_page=page 429
}}<!--

--><span class="statement" id="st-d0_s0" data-properties="whole-organism some measurement;whole-organism duration"><b>Perennials,</b> 30–100 cm.</span> <span class="statement" id="st-d0_s1" data-properties="stem quantity;stem architecture;stem architecture;stem pubescence"><b>Stems </b>usually 1, usually branched distally, strongly winged, glabrous or sparsely hairy proximally, sparsely to moderately hairy distally.</span> <span class="statement" id="st-d0_s2" data-properties="leaf pubescence"><b>Leaves </b>glabrous or sparsely to moderately hairy;</span> <span class="statement" id="st-d0_s3" data-properties="basal blade shape;basal blade architecture or shape;basal blade architecture or shape">basal blades oblanceolate to obovate or spatulate, entire or serrate;</span> <span class="statement" id="st-d0_s4" data-properties="proximal mid-blade shape;proximal mid-blade shape">proximal and mid-blades oblanceolate to lanceolate, entire or toothed;</span> <span class="statement" id="st-d0_s5" data-properties="distal blade shape;distal blade architecture or shape">distal blades lanceolate to lance-linear, entire.</span> <span class="statement" id="st-d0_s6" data-properties="head atypical quantity;head atypical quantity;head quantity;array architecture"><b>Heads </b>(1–) 5–50 (–80+) per plant, in paniculiform arrays.</span> <span class="statement" id="st-d0_s7" data-properties="peduncle some measurement;peduncle pubescence"><b>Peduncles </b>3–10 cm, sparsely to moderately hairy.</span> <span class="statement" id="st-d0_s8" data-properties="involucre shape;involucre length;involucre width"><b>Involucres </b>globoid to usually ovoid, 8–17 × 9–17 mm.</span> <span class="statement" id="st-d0_s9" data-properties="phyllary pubescence"><b>Phyllaries </b>(connate proximally) moderately to densely hairy.</span> <span class="statement" id="st-d0_s10" data-properties="ray-floret quantity;ray-floret architecture;ray-floret presence"><b>Ray-</b>florets usually 8–13, neuter, sometimes 0;</span> <span class="statement" id="st-d0_s11" data-properties="corolla coloration;corolla length;corolla width">corollas yellow to reddish-brown to red to purple, 10–20 × 5–10 mm.</span> <span class="statement" id="st-d0_s12" data-properties="disc-floret atypical quantity;disc-floret quantity"><b>Disc-</b>florets 250–500 (–700+);</span> <span class="statement" id="st-d0_s13" data-properties="corolla coloration;corolla coloration or density;corolla coloration or density;corolla some measurement;lobe atypical quantity;lobe quantity">corollas yellow proximally and purple distally or purple throughout, 2.3–3.7 mm, lobes 4 (–5).</span> <span class="statement" id="st-d0_s14" data-properties="cypsela some measurement;cypsela pubescence"><b>Cypselae </b>1–1.2 mm, moderately hairy;</span> <span class="statement" id="st-d0_s15" data-properties="scale quantity;scale architecture or shape;scale shape;scale atypical some measurement;scale some measurement">pappi of 5–6 entire, aristate scales 0.6–1 (–1.7) mm.</span> <span class="statement" id="st-d0_s16" data-properties="2n chromosome quantity">2n = 28.</span><!--

-->{{Treatment/Body
|phenology=Flowering (Apr–)May–Jul(–Oct).
|habitat=Ditches, fields, washes, along streams
|elevation=10–900 m
|distribution=N.S.;Ont.;Que.;Ala.;Ark.;Fla.;Ga.;Ill.;Ind.;Ky.;La.;Md.;Mass.;Mich.;Miss.;Mo.;N.J.;N.C.;Ohio;Okla.;Pa.;S.C.;Tenn.;Tex.;Va.;W.Va.;Wis.
|discussion=<p>It has been suggested that Helenium flexuosum may be of hybrid origin from H. campestre (perennial, 2n = 28) and some member of Helenium sect. Tetrodus (H. F. L. Rock 1957). The only member of sect. Tetrodus that has a chromosome number of 2n = 28 is H. linifolium, an annual from southern Texas.</p>
|tables=
|references=
}}<!--

--><!--

-->{{#Taxon:
name=Helenium flexuosum
|authority=Rafinesque
|rank=species
|parent rank=genus
|synonyms=Helenium nudiflorum
|basionyms=
|family=Asteraceae
|phenology=Flowering (Apr–)May–Jul(–Oct).
|habitat=Ditches, fields, washes, along streams
|elevation=10–900 m
|distribution=N.S.;Ont.;Que.;Ala.;Ark.;Fla.;Ga.;Ill.;Ind.;Ky.;La.;Md.;Mass.;Mich.;Miss.;Mo.;N.J.;N.C.;Ohio;Okla.;Pa.;S.C.;Tenn.;Tex.;Va.;W.Va.;Wis.
|reference=None
|publication title=New Fl.
|publication year=1838
|special status=Endemic
|source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V19-20-21/V21_1073.xml
|tribe=Asteraceae tribe Heliantheae
|subtribe=Asteraceae (tribe Heliantheae) subtribe Gaillardiinae
|genus=Helenium
|species=Helenium flexuosum
|2n chromosome quantity=28
|array architecture=paniculiform
|basal blade architecture or shape=serrate;entire
|basal blade shape=oblanceolate;obovate or spatulate
|corolla coloration=yellow;yellow;reddish-brown
|corolla coloration or density=purple;purple
|corolla length=10mm;20mm
|corolla some measurement=2.3mm;3.7mm
|corolla width=5mm;10mm
|cypsela pubescence=hairy
|cypsela some measurement=1mm;1.2mm
|disc-floret atypical quantity=500;700
|disc-floret quantity=250;500
|distal blade architecture or shape=entire
|distal blade shape=lanceolate;lance-linear
|head atypical quantity=50;80
|head quantity=5;50
|involucre length=8mm;17mm
|involucre shape=ovoid
|involucre width=9mm;17mm
|leaf pubescence=glabrous or;sparsely moderately hairy
|lobe atypical quantity=4;5
|lobe quantity=4
|peduncle pubescence=hairy
|peduncle some measurement=3cm;10cm
|phyllary pubescence=hairy
|proximal mid-blade shape=oblanceolate;lanceolate entire or toothed
|ray-floret architecture=neuter
|ray-floret presence=absent
|ray-floret quantity=8;13
|scale architecture or shape=entire
|scale atypical some measurement=1mm;1.7mm
|scale quantity=5;6
|scale shape=aristate
|scale some measurement=0.6mm;1mm
|stem architecture=winged;branched
|stem pubescence=sparsely hairy proximally;sparsely moderately hairy
|stem quantity=1
|whole-organism duration=perennial
|whole-organism some measurement=30cm;100cm
}}<!--

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