View source for Polygonum achoreum

{{Treatment/ID
|accepted_name=Polygonum achoreum
|accepted_authority=S. F. Blake
|publications={{Treatment/Publication
|title=Rhodora
|place=19: 232. 1917
|year=1917
}}
|common_names=Blake’s knotweed;renouée coriace
|special_status={{Treatment/ID/Special_status
|code=E
|label=Endemic
}}
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Polygonum erectum subsp. achoreum
|authority=(S. F. Blake) Á. Löve & D. Löve
|rank=subspecies
}}
|hierarchy=Polygonaceae;Polygonaceae subfam. Polygonoideae;Polygonum;Polygonum sect. Polygonum;Polygonum achoreum
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Polygonaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Polygonaceae subfam. Polygonoideae]]</div><div class="higher-taxon"><small>genus</small>[[Polygonum]]</div><div class="higher-taxon"><small>section</small>[[Polygonum sect. Polygonum]]</div><div class="higher-taxon"><small>species</small>[[Polygonum achoreum]]</div></div>
|volume=Volume 5
|mention_page=page 549
|treatment_page=page 551
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>light green (often covered with whitish powdery mildew), homophyllous or, sometimes, heterophyllous. <b>Stems</b> erect when young, decumbent or prostrate later, moderately branched especially from base, not wiry, 50–70 cm. <b>Leaves</b>: ocreae 5–12 mm, proximal part cylindric, distal part soon disintegrating into brown fibers; petiole 0.3–1.5 mm; blade light yellowish green, elliptic to obovate, 8–35 × 3–15 mm, margins flat, apex rounded; stem leaves 1–2.1(–3) times longer than branch leaves; distal leaves overtopping flowers. <b>Inflorescences</b> axillary, cymes in axils of most leaves and toward tips of stems and branchs, 1–3(–5)-flowered. <b>Pedicels</b> enclosed in ocreae, 1.3–1.8(–2) mm. <b>Flowers</b> closed; perianth 2.6–4 mm; tube 40–55% of perianth length; tepals incurved, yellow-green with yellow to green, rarely pinkish, margins, sepaloid, ± keeled, narrowly oblong, cucullate; midveins unbranched, moderately to heavily thickened, tepals appearing keeled; stamens 5–8. <b>Achenes</b> enclosed in perianth, yellow-green to tan, ovate, 3-gonous, 2.4–3.5 mm, faces unequal, apex not beaked, edges concave or nearly straight, dull, uniformly tubercled; late-season achenes common, 3–5 mm. <b>2n</b> = 40, 60.</span><!--

-->{{Treatment/Body
|phenology=Flowering Jul–Sep.
|habitat=Disturbed areas, roadsides, sidewalks, edges of cultivated fields
|elevation=10-800 m
|distribution=Alta.;B.C.;Man.;N.B.;N.W.T.;N.S.;Ont.;Que.;Sask.;Yukon;Alaska;Colo.;Conn.;Idaho;Ill.;Ind.;Iowa;Kans.;Maine;Mich.;Minn.;Mo.;Mont.;Nebr.;Nev.;N.Y.;N.Dak.;Ohio;Oreg.;S.Dak.;Utah;Vt.;Wash.;W.Va.;Wis.;Wyo.
|discussion=<p><i>Polygonum achoreum</i> frequently is confused with <i>P. erectum</i>. It can be distinguished by its usually homophyllous leaves, its perianth, which is enlarged at the base and constricted above the fruit, its longer perianth tube, and its yellow-green to tan, tubercled achenes.</p>
|tables=
|references=
}}<!--

--><!--

-->{{#Taxon:
name=Polygonum achoreum
|authority=S. F. Blake
|rank=species
|parent rank=section
|synonyms=Polygonum erectum subsp. achoreum
|basionyms=
|family=Polygonaceae
|phenology=Flowering Jul–Sep.
|habitat=Disturbed areas, roadsides, sidewalks, edges of cultivated fields
|elevation=10-800 m
|distribution=Alta.;B.C.;Man.;N.B.;N.W.T.;N.S.;Ont.;Que.;Sask.;Yukon;Alaska;Colo.;Conn.;Idaho;Ill.;Ind.;Iowa;Kans.;Maine;Mich.;Minn.;Mo.;Mont.;Nebr.;Nev.;N.Y.;N.Dak.;Ohio;Oreg.;S.Dak.;Utah;Vt.;Wash.;W.Va.;Wis.;Wyo.
|reference=None
|publication title=Rhodora
|publication year=1917
|special status=Endemic
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V5/V5_1121.xml
|subfamily=Polygonaceae subfam. Polygonoideae
|genus=Polygonum
|section=Polygonum sect. Polygonum
|species=Polygonum achoreum
}}<!--

-->[[Category:Treatment]][[Category:Polygonum sect. Polygonum]]