View source for Polygonum aviculare subsp. boreale

{{Treatment/ID
|accepted_name=Polygonum aviculare subsp. boreale
|accepted_authority=(Lange) Karlsson
|publications={{Treatment/Publication
|title=Svensk Bot. Tidskr.
|place=91: 249. 1998
|year=1998
}}
|common_names=Northern knotweed
|basionyms={{Treatment/ID/Basionym
|name=Polygonum aviculare var. boreale
|authority=Lange
|rank=variety
|publication_title=Consp. Fl. Groenland.
|publication_place=1: 105. 1880
}}
|synonyms={{Treatment/ID/Synonym
|name=Polygonum arenastrum subsp. boreale
|authority=(Lange) Á. Löve
|rank=subspecies
}} {{Treatment/ID/Synonym
|name=Polygonum boreale
|authority=Lindman
|rank=species
}} {{Treatment/ID/Synonym
|name=Polygonum heterophyllum subsp. boreale
|authority=(Lange) Á. Löve & D. Löve
|rank=subspecies
}}
|hierarchy=Polygonaceae;Polygonaceae subfam. Polygonoideae;Polygonum;Polygonum sect. Polygonum;Polygonum aviculare;Polygonum aviculare subsp. boreale
|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 aviculare]]</div><div class="higher-taxon"><small>subspecies</small>[[Polygonum aviculare subsp. boreale]]</div></div>
|volume=Volume 5
|mention_page=page 556
|treatment_page=page 557
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>green, homophyllous or subheterophyllous. <b>Stems</b> 1–7, prostrate to ascending, mostly branching from base, 6–50(–90) cm. <b>Leaves</b>: ocrea 3.5–7 mm, proximal part cylindric to funnelform, distal part soon disintegrating, nearly completely deciduous; petiole 7–9 mm; blade green, lateral veins visible but not raised abaxially, obovate-spatulate or oblanceolate, (12.5–)16–44(–55) × (4–)6–18(–22) mm, 2–4(–5.5) times as long as wide, apex obtuse to rounded; stem leaves (1.1–)1.3–2.5(–3) times as long as branch leaves. <b>Cymes</b> uniformly distributed, rarely crowded at tips of stems and branches, (3–)4–7-flowered. <b>Pedicels</b> mostly exserted from ocreae, 2–5 mm. <b>Flowers</b>: perianth 3.3–5.5 mm, 1.6–2.8 times as long as wide; tube 25–35(–39)% of perianth length; tepals overlapping, green with white or pink margins, obovate, flat or curved outward in fruit, outer tepals not pouched at base; veins branched, thickened; stamens 6–8. <b>Achenes</b> enclosed in perianth, dark brown, ovate, 3-gonous, (2.5–)2.7–4(–4.2) mm, faces subequal, concave, apex straight, coarsely striate-tubercled; late-season achenes uncommon, 4–5 mm. <b>2n</b> = 40.</span><!--

-->{{Treatment/Body
|phenology=Flowering Aug–Oct.
|habitat=Sandy, gravelly, or rocky coastal areas
|elevation=0-500 m
|distribution=Greenland;Nfld. and Labr. (Labr.);nw Europe.
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Polygonum aviculare subsp. boreale
|authority=(Lange) Karlsson
|rank=subspecies
|parent rank=species
|synonyms=Polygonum arenastrum subsp. boreale;Polygonum boreale;Polygonum heterophyllum subsp. boreale
|basionyms=Polygonum aviculare var. boreale
|family=Polygonaceae
|phenology=Flowering Aug–Oct.
|habitat=Sandy, gravelly, or rocky coastal areas
|elevation=0-500 m
|distribution=Greenland;Nfld. and Labr. (Labr.);nw Europe.
|reference=None
|publication title=Svensk Bot. Tidskr.
|publication year=1998
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f50eec43f223ca0e34566be0b046453a0960e173/coarse_grained_fna_xml/V5/V5_1138.xml
|subfamily=Polygonaceae subfam. Polygonoideae
|genus=Polygonum
|section=Polygonum sect. Polygonum
|species=Polygonum aviculare
|subspecies=Polygonum aviculare subsp. boreale
}}<!--

-->[[Category:Treatment]][[Category:Polygonum aviculare]]