View source for Centaurea calcitrapa

{{Treatment/ID
|accepted_name=Centaurea calcitrapa
|accepted_authority=Linnaeus
|publications={{Treatment/Publication
|title=Sp. Pl.
|place=2: 917. 1753
|year=1753
}}
|common_names=Purple star-thistle;caltrops;chausse-trappe;centaurée chausse-trappe
|special_status={{Treatment/ID/Special_status
|code=I
|label=Introduced
}}
|basionyms=
|synonyms=
|hierarchy=Asteraceae;Asteraceae tribe Cardueae;Centaurea;Centaurea calcitrapa
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Cardueae]]</div><div class="higher-taxon"><small>genus</small>[[Centaurea]]</div><div class="higher-taxon"><small>species</small>[[Centaurea calcitrapa]]</div></div>
|volume=Volume 19
|mention_page=page 183, 192
|treatment_page=page 191
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Annuals,</b> biennials, or short-lived perennials, 20–100 cm. <b>Stems</b> 1–several, often forming rounded mounds, puberulent to loosely tomentose. <b>Leaves</b> puberulent to loosely gray-tomentose, becoming ± glabrous, minutely resin-gland-dotted; proximal leaves petiolate, blades 10–20 cm, 1–3 times pinnately dissected, rosette with central cluster of spines; mid sessile, not decurrent, blades ovate, usually less than 10 cm, narrowly lobed; distal blades linear to oblong, entire to shallowly lobed. <b>Heads</b> disciform, borne singly or in leafy cymiform arrays, sessile or short-pedunculate. <b>Involucres</b> ovoid, 15–20 × 6–8 mm. <b>Principal</b> phyllaries: bodies greenish or stramineous, ovate, scarious-margined, appendages stramineous, spiny fringed at base, each tipped by a stout spreading spine 10–25 mm. <b>Inner</b> phyllaries: appendages truncate, spineless. <b>Florets</b> 25–40; corollas purple, all ± equal, 15–24 mm; sterile corollas slender. <b>Cypselae</b> white or brown-streaked, 2.5–3.4 mm, glabrous; pappi 0. <b>2n</b> = 20.</span><!--

-->{{Treatment/Body
|phenology=Flowering summer–autumn (Jun–Nov).
|habitat=Pastures, fields, roadsides
|elevation=0–1700 m
|distribution=Ont.;Ala.;Ariz.;Calif.;D.C.;Fla.;Ga.;Ill.;Iowa;Md.;Mass.;N.J.;N.Mex.;N.Y.;Oreg.;Pa.;Utah;Va.;Wash.;Europe;Africa.
|discussion=<p><i>Centaurea calcitrapa</i> is native to southern Europe and northern Africa. It is listed as a noxious weed in Arizona, California, <i>Nevada</i>, New Mexico, Oregon, and Washington. These plants are unpalatable and increase on rangelands as more desirable forage plants are consumed. Dense stands are impenetrable because of the vicious spines on the mature involucres.</p><!--
--><p><i>Centaurea</i> ×pouzinii de Candolle, an apparently stabilized hybrid between <i>Centaurea</i> aspera (2n = 22) and <i>C. calcitrapa</i> (2n = 20), has been reported from California. A chromosome count of 2n = 42 has been reported from California material of this nothospecies (A. M. Powell et al. 1974). <i>Centaurea</i> ×pouzinii can be distinguished from <i>C. calcitrapa</i> by its shorter spines and by cypselae with a short pappus. Reports of C. calcitrapoides Linnaeus from North America are apparently based on this hybrid.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Centaurea calcitrapa
|authority=Linnaeus
|rank=species
|parent rank=genus
|synonyms=
|basionyms=
|family=Asteraceae
|phenology=Flowering summer–autumn (Jun–Nov).
|habitat=Pastures, fields, roadsides
|elevation=0–1700 m
|distribution=Ont.;Ala.;Ariz.;Calif.;D.C.;Fla.;Ga.;Ill.;Iowa;Md.;Mass.;N.J.;N.Mex.;N.Y.;Oreg.;Pa.;Utah;Va.;Wash.;Europe;Africa.
|reference=None
|publication title=Sp. Pl.
|publication year=1753
|special status=Introduced
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V19-20-21/V19_221.xml
|tribe=Asteraceae tribe Cardueae
|genus=Centaurea
|species=Centaurea calcitrapa
}}<!--

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