View source for Spiraea alba

{{Treatment/ID
|accepted_name=Spiraea alba
|accepted_authority=Du Roi
|publications={{Treatment/Publication
|title=Harbk. Baumz.
|place=2: 430. 1772
|year=1772
}}
|common_names=Narrow-leaf;eastern;or white meadowsweet;spirée blanche
|special_status={{Treatment/ID/Special_status
|code=E
|label=Endemic
}}{{Treatment/ID/Special_status
|code=F
|label=Illustrated
}}{{Treatment/ID/Special_status
|code=W
|label=Weedy
}}
|basionyms=
|synonyms=
|hierarchy=Rosaceae;Rosaceae subfam. Amygdaloideae;Rosaceae tribe Spiraeeae;Spiraea;Spiraea alba
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Rosaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Rosaceae subfam. Amygdaloideae]]</div><div class="higher-taxon"><small>tribe</small>[[Rosaceae tribe Spiraeeae]]</div><div class="higher-taxon"><small>genus</small>[[Spiraea]]</div><div class="higher-taxon"><small>species</small>[[Spiraea alba]]</div></div>
|volume=Volume 9
|mention_page=page 399
|treatment_page=page 401
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Shrubs,</b> 10–20 dm. <b>Stems</b> erect, unbranched. <b>Leaves</b>: petiole 2–8 mm, puberulent or sparsely hairy; blade narrowly lanceolate to oblanceolate or broadly oblanceolate to obovate, 2–9 × 0.5–3 cm, length 3–5 times width, chartaceous or membranous, base cuneate to rounded, margins finely to coarsely, sharply serrate to serrulate (sometimes doubly so on long shoot leaves), number of primary and secondary serrations 0.5–1.1 times number of secondary veins (excluding inter-secondary veins), venation pinnate craspedodromous, secondary veins not prominent, irregularly terminating in primary teeth, inter-secondary veins usually 8–12+ per leaf, apex acute to obtuse, abaxial surface mostly glabrous, adaxial glabrous. <b>Inflorescences</b> mostly terminal, narrowly conic to open, pyramidal panicles, 5–20 × 3–10 cm height 1.4–3.5 times diam.; branches usually in axils of leaves, puberulent to pubescent. <b>Pedicels</b> 1–2(–3) mm, glabrous or glabrate. <b>Flowers</b> 3–8 mm diam.; hypanthia hemispheric, 0.6–0.8 mm, abaxial surface usually puberulent to sparsely strigose, sometimes glabrate or glabrous, adaxial glabrous; sepals triangular, 0.8–1.5 mm; petals usually white, sometimes pink-tinged (in bud), suborbiculate, 1.3–2(–3) mm; staminodes 0–4; stamens 30–50, 1–2 times petal length. <b>Follicles</b> oblanceoloid, 3–4 mm, shiny, glabrous.</span><!--

-->{{Treatment/Body
|distribution=Alta.;Man.;N.B.;N.S.;Ont.;P.E.I.;Que.;Sask.;Conn.;Del.;Ill.;Ind.;Iowa;Ky.;Maine;Mass.;Md.;Mich.;Minn.;Mo.;N.C.;N.Dak.;N.H.;N.J.;N.Y.;Ohio;Pa.;R.I.;S.Dak.;Tenn.;Va.;Vt.;W.Va.;Wis.;introduced in Europe.
|discussion=<p>Varieties 2 (2 in the flora).</p><!--
--><p>Varieties alba and latifolia have regions of hybridization, primarily around the Great Lakes, that produce intermediate forms that may be difficult to key. Recognition of these two taxa as either species or varieties has been problematic because the taxa are quite distinct at the extremes of their range. A. R. Kugel (1958) recognized them as distinct species and her work illustrates the regional zone of hybridization. H. A. Gleason (1952) and Gleason and A. Cronquist (1963) also recognized the two taxa as separate species; later Gleason and Cronquist (1991) recognized them as varieties that frequently intergrade.</p><!--
--><p>The European <i>Spiraea salicifolia</i> has a leaf morphology that is similar to that of <i></i>var.<i> alba</i> and the two taxa have been treated as conspecific. With the interest in <i>Spiraea</i> as an ornamental, <i>S. salicifolia</i> was imported to North America, resulting in this species or hybrids of it becoming naturalized. Specimens that are difficult to identify may be <i>S. salicifolia</i>, as escapes from homesteads and gardens that became established or may have hybridized with native taxa.</p><!--
--><p><i>Spiraea alba</i> has become locally naturalized in western and central Europe; in the British Isles, its hybrids are commonly naturalized as S. ×rosalba Dippel (<i>S. alba</i> × <i>S. salicifolia</i>), or as S. ×billardii Hortus ex K. Koch (<i>S. alba</i> × <i>S. douglasii</i>) (A. J. Silverside 1990).</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Leaves: lengths 3–4 times widths, margins finely serrate to serrulate; inflorescences narrowly conic.
|[[Spiraea alba var. alba|Spiraea alba var. alba]]
|-id=key-0-1
|1
|Leaves: lengths 2–3 times widths, margins coarsely serrate; inflorescences open, pyramidal.
|[[Spiraea alba var. latifolia|Spiraea alba var. latifolia]]
|}
</div></div><!--

-->{{#Taxon:
name=Spiraea alba
|authority=Du Roi
|rank=species
|parent rank=genus
|synonyms=
|basionyms=
|family=Rosaceae
|distribution=Alta.;Man.;N.B.;N.S.;Ont.;P.E.I.;Que.;Sask.;Conn.;Del.;Ill.;Ind.;Iowa;Ky.;Maine;Mass.;Md.;Mich.;Minn.;Mo.;N.C.;N.Dak.;N.H.;N.J.;N.Y.;Ohio;Pa.;R.I.;S.Dak.;Tenn.;Va.;Vt.;W.Va.;Wis.;introduced in Europe.
|reference=None
|publication title=Harbk. Baumz.
|publication year=1772
|special status=Endemic;Illustrated;Weedy
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V9/V9_668.xml
|subfamily=Rosaceae subfam. Amygdaloideae
|tribe=Rosaceae tribe Spiraeeae
|genus=Spiraea
|species=Spiraea alba
}}<!--

-->

[[Category:Treatment]]
[[Category:Spiraea]]
[[Category:Revised Since Print]]