View source for Matricaria discoidea

{{Treatment/ID
|accepted_name=Matricaria discoidea
|accepted_authority=de Candolle in A. P. de Candolle and A. L. P. P. de Candolle
|publications={{Treatment/Publication
|title=in A. P. de Candolle and A. L. P. P. de Candolle, Prodr.
|place=6: 50. 1838
|year=1838
}}
|common_names=Pineappleweed;disc mayweed;rayless chamomile;matricaire odorante
|basionyms={{Treatment/ID/Basionym
|name=Santolina suaveolens
|authority=Pursh
|publication_title=
|publication_place=1813
}}
|synonyms={{Treatment/ID/Synonym
|name=Chamomilla suaveolens
|authority=(Pursh) Rydberg
}} {{Treatment/ID/Synonym
|name=Chamomilla discoidea
|authority=(de Candolle) J. Gay ex A. Braun
}}
|hierarchy=Asteraceae;Asteraceae tribe Anthemideae;Matricaria;Matricaria discoidea
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Anthemideae]]</div><div class="higher-taxon"><small>genus</small>[[Matricaria]]</div><div class="higher-taxon"><small>species</small>[[Matricaria discoidea]]</div></div>
|volume=Volume 19
|mention_page=
|treatment_page=page 541
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Annuals,</b> (1–)4–40(–50) cm; aromatic (pineapple odor when bruised). <b>Stems</b> 1–10+, usually erect or ascending, sometimes decumbent, branched from bases. <b>Leaf</b> blades (5–)10–65(–85) × 2–20 mm. <b>Heads</b> discoid, (1–)4–50(–300), usually borne singly, sometimes in open, corymbiform arrays. <b>Peduncles</b> 2–25(–30) mm (sometimes villous near heads). <b>Involucres</b> 2.5–3.8 mm. <b>Phyllaries</b> 29–47+ in 3 series, margins mostly entire. <b>Receptacles</b> 2.5–7.5 mm, ± acute or obtuse. <b>Ray</b> florets 0. <b>Discs</b> hemispheric to broadly ovoid, 4–7(–11) × 4–7.5(–10) mm. <b>Disc</b> florets 125–535+; corollas greenish yellow, 1.1–1.3 mm (± glandular), lobes 4(–5). <b>Cypselae</b> pale brown to tan, ± cylindric-obconic (asymmetric, abaxially ± gibbous distally), 1.15–1.5 mm, ribs white (lateral 2 each with reddish brown mucilage gland along ± entire length, glands sometimes distally expanded, abaxial 1–2 weak, sometimes each with elongate mucilaginous gland), faces not glandular; pappi coroniform, entire. <b>2n</b> = 18. [as M. matricarioides]</span><!--

-->{{Treatment/Body
|phenology=Flowering early summer–fall.
|habitat=Open areas, bare disturbed areas and rural or urban waste grounds, sometimes alkaline, roadsides, railroads, footpaths, cultivated and abandoned fields and gardens, irrigation ditches, stream banks, sandbars
|elevation=0–2700 m
|distribution=Greenland;St. Pierre and Miquelon;Alta.;B.C.;Man.;N.B.;Nfld. and Labr.;N.W.T.;N.S.;Ont.;P.E.I.;Que.;Sask.;Yukon;Alaska;Ariz.;Ark.;Calif.;Colo.;Conn.;Del.;Idaho;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Maine;Md.;Mass.;Mich.;Minn.;Miss.;Mo.;Mont.;Nev.;N.H.;N.J.;N.Mex.;N.Y.;N.C.;N.Dak.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;S.Dak.;Tenn.;Tex.;Utah;Vt.;Va.;Wash.;W.Va.;Wis.;Wyo.;introduced in Eurasia;Australia.
|discussion=<p><i>Matricaria discoidea</i> has been used as a medicinal and aromatic plant by Native American tribes (D. E. Moerman 1998). It also is considered a weed, and it is resistant to a photosystem II inhibitor herbicide in the United Kingdom (www.weedscience.org). It is a northwestern North American native that has spread to eastern and northern North America and elsewhere (E. McClintock 1993b; E. G. Voss 1972–1996, vol. 3; A. Cronquist 1994). NatureServe (www.natureserve.org) and Natural Resources Conservation Service (plants.usda.gov) erroneously present <i>M. discoidea</i> as introduced on the continent. Its natural habitat is ill-defined because the species has become ruderal even in its native range. For discussion of the nomenclature of this taxon, see S. Rauschert (1974); K. N. Gandhi and R. D. Thomas (1991); Cronquist; and Voss.</p><!--
--><p>“<i>Matricaria</i> matricarioides (Lessing) Porter” cannot be applied to the American taxon; M. matricarioides was originally published as <i>Artemisia</i> matricarioides Lessing, a new name for <i>Tanacetum</i> pauciflorum Richardson (see S. Rauschert 1974), itself a synonym of T. huronense Nuttall. W. Greuter (pers. comm.), who accepts M. discodea, considers Rauschert’s treating <i>Artemisia</i> matricarioides as homotypic with T. pauciflorum as equivalent to a lectotype designation.</p>
|tables=
|references=
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-->{{#Taxon:
name=Matricaria discoidea
|author=
|authority=de Candolle in A. P. de Candolle and A. L. P. P. de Candolle
|rank=species
|parent rank=genus
|synonyms=Chamomilla suaveolens;Chamomilla discoidea
|basionyms=Santolina suaveolens
|family=Asteraceae
|phenology=Flowering early summer–fall.
|habitat=Open areas, bare disturbed areas and rural or urban waste grounds, sometimes alkaline, roadsides, railroads, footpaths, cultivated and abandoned fields and gardens, irrigation ditches, stream banks, sandbars
|elevation=0–2700 m
|distribution=Greenland;St. Pierre and Miquelon;Alta.;B.C.;Man.;N.B.;Nfld. and Labr.;N.W.T.;N.S.;Ont.;P.E.I.;Que.;Sask.;Yukon;Alaska;Ariz.;Ark.;Calif.;Colo.;Conn.;Del.;Idaho;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Maine;Md.;Mass.;Mich.;Minn.;Miss.;Mo.;Mont.;Nev.;N.H.;N.J.;N.Mex.;N.Y.;N.C.;N.Dak.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;S.Dak.;Tenn.;Tex.;Utah;Vt.;Va.;Wash.;W.Va.;Wis.;Wyo.;introduced in Eurasia;Australia.
|reference=None
|publication title=in A. P. de Candolle and A. L. P. P. de Candolle, Prodr.
|publication year=1838
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V19-20-21/V19_941.xml
|tribe=Asteraceae tribe Anthemideae
|genus=Matricaria
|species=Matricaria discoidea
}}<!--

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