View source for Amaranthus powellii

{{Treatment/ID
|accepted_name=Amaranthus powellii
|accepted_authority=S. Watson
|publications={{Treatment/Publication
|title=Proc. Amer. Acad. Arts
|place=10: 347. 1875
|year=1875
}}
|common_names=Powell’s amaranth;green amaranth;Powell’s smooth amaranth
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Amaranthus bracteosus
|authority=Uline & W. L. Bray
|rank=species
}} {{Treatment/ID/Synonym
|name=Amaranthus retroflexus var. powellii
|authority=(S. Watson) B. Boivin
|rank=variety
}}
|hierarchy=Amaranthaceae;Amaranthus;Amaranthus subg. Amaranthus;Amaranthus powellii
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Amaranthaceae]]</div><div class="higher-taxon"><small>genus</small>[[Amaranthus]]</div><div class="higher-taxon"><small>subgenus</small>[[Amaranthus subg. Amaranthus]]</div><div class="higher-taxon"><small>species</small>[[Amaranthus powellii]]</div></div>
|volume=Volume 4
|mention_page=page 424
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>glabrous or moderately pubescent toward inflorescences, becoming glabrescent at maturity. <b>Stems</b> usually erect, green or sometimes reddish purple, branched, mainly in inflorescences, to nearly simple, 0.3–1.5(–2) m, stiff. <b>Leaves</b>: petiole mostly equaling or longer than blade; blade rhombic-ovate to broadly lanceolate, 4–8 × 2–3 cm, occasionally larger in robust plants, base cuneate to broadly cuneate, margins entire, apex cuneate to obtuse or indistinctly emarginate, with mucro. <b>Inflorescences</b> mostly terminal, usually with spikes at distal axils, erect and rigid, green to silvery green, occasionally tinged red, leafless at least distally. <b>Bracts</b> lanceolate to linear-subulate, 4–7 mm, 2–3 times as long as tepals, rigid. <b>Pistillate</b> flowers: tepals usually 3–5, not clawed, unequal; outer tepals narrowly ovate-elliptic or elliptic, 1.5–3.5 mm, apex aristate; style branches spreading, shorter than body of fruit; stigmas 3. <b>Staminate</b> flowers clustered at tips of inflorescence branches; tepals 3–5; stamens 3–5. <b>Utricles</b> subglobose or compressed-ovoid, 2–3 mm, equaling or shorter than tepals, smooth or lid slightly rugose or minutely verrucose, dehiscence regularly circumscissile. <b>Seeds</b> black, subglobose to lenticular, 1–1.4 mm diam., smooth, shiny.</span><!--

-->{{Treatment/Body
|phenology=Flowering summer–fall.
|habitat=Disturbed habitats, agricultural fields, railroads, roadsides, waste areas, banks of rivers, lakes, and streams
|elevation=0-2500 m
|distribution=Alta.;B.C.;Ont.;P.E.I.;Que.;Sask.;Ariz.;Ark.;Calif.;Colo.;Conn.;Fla.;Idaho;Ill.;Ind.;Kans.;Ky.;La.;Maine;Mass.;Mich.;Minn.;Miss.;Mo.;Mont.;Nev.;N.H.;N.J.;N.Mex.;N.Y.;N.C.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;S.Dak.;Tenn.;Tex.;Utah;Vt.;Va.;Wash.;W.Va.;Wis.;Wyo.;Mexico;introduced or naturalized in South America;Eurasia;Australia.
|discussion=<p><i>Amaranthus powellii</i> is originally native to southwestern United States and adjacent regions of Mexico; now, it is widely naturalized almost everywhere in temperate regions of North America. The distribution of <i>A. powellii</i> is probably underestimated both in North America and the Old World, and literature references are somewhat confusing, because <i>A. powellii</i> has been commonly confused with <i>A. hybridus</i>.</p><!--
--><p>Forms of <i>Amaranthus powellii</i> with indehiscent or occasionally irregularly dehiscent utricles were described from Europe (southwestern France, the Gironde estuary) as A. bouchonii Thellung. Similar forms occasionally occur in North America. According to J. M. Tucker and J. D. Sauer (1958) and J. D. Sauer (1967b, 1972b), they are mostly “mutant or aberrant forms” of <i>A. powellii</i>, or hybrids of <i>A. powellii</i> and/or <i>A. hybridus</i> with other species. Recent comparative studies of morphology and isozymes of A. bouchonii (P. Wilkin 1992) indicated that that taxon, whatever its origin was, now differs from its presumably parental species and probably deserves recognition, at least as a separate subspecies. It seems that in North America, the situation with indehiscent-fruited forms is much more complicated than in Europe, and multiple entities are involved, including deviate forms of <i>A. powellii</i> and also partly sterile hybrids of dioecious taxa with species belonging to the <i>A. hybridus</i> group. The formal recognition of A. bouchonii in North American material would be premature.</p><!--
--><p>The names <i>Amaranthus hybridus</i>, A. chlorostachys Willdenow, and <i>A. hybridus</i> subsp. chlorostachys (Willdenow) Hejný were occasionally misapplied to <i>A. powellii</i> in North America and Europe.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Amaranthus powellii
|authority=S. Watson
|rank=species
|parent rank=subgenus
|synonyms=Amaranthus bracteosus;Amaranthus retroflexus var. powellii
|basionyms=
|family=Amaranthaceae
|phenology=Flowering summer–fall.
|habitat=Disturbed habitats, agricultural fields, railroads, roadsides, waste areas, banks of rivers, lakes, and streams
|elevation=0-2500 m
|distribution=Alta.;B.C.;Ont.;P.E.I.;Que.;Sask.;Ariz.;Ark.;Calif.;Colo.;Conn.;Fla.;Idaho;Ill.;Ind.;Kans.;Ky.;La.;Maine;Mass.;Mich.;Minn.;Miss.;Mo.;Mont.;Nev.;N.H.;N.J.;N.Mex.;N.Y.;N.C.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;S.Dak.;Tenn.;Tex.;Utah;Vt.;Va.;Wash.;W.Va.;Wis.;Wyo.;Mexico;introduced or naturalized in South America;Eurasia;Australia.
|reference=None
|publication title=Proc. Amer. Acad. Arts
|publication year=1875
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f50eec43f223ca0e34566be0b046453a0960e173/coarse_grained_fna_xml/V4/V4_830.xml
|genus=Amaranthus
|subgenus=Amaranthus subg. Amaranthus
|species=Amaranthus powellii
}}<!--

-->[[Category:Treatment]][[Category:Amaranthus subg. Amaranthus]]