View source for Potentilla effusa

{{Treatment/ID
|accepted_name=Potentilla effusa
|accepted_authority=Douglas ex Lehmann
|publications={{Treatment/Publication
|title=Nov. Stirp. Pug.
|place=2: 8. 1830
|year=1830
}}
|special_status={{Treatment/ID/Special_status
|code=E
|label=Endemic
}}{{Treatment/ID/Special_status
|code=F
|label=Selected by author to be illustrated
}}
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Potentilla hippiana subsp. effusa
|authority=(Douglas ex Lehmann) Dorn
}} {{Treatment/ID/Synonym
|name=P. hippiana var. effusa
|authority=(Douglas ex Lehmann) Dorn
}}
|hierarchy=Rosaceae;Rosaceae subfam. Rosoideae;Rosaceae tribe Potentilleae;Potentilla;Potentilla sect. Leucophyllae;Potentilla effusa
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Rosaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Rosaceae subfam. Rosoideae]]</div><div class="higher-taxon"><small>tribe</small>[[Rosaceae tribe Potentilleae]]</div><div class="higher-taxon"><small>genus</small>[[Potentilla]]</div><div class="higher-taxon"><small>section</small>[[Potentilla sect. Leucophyllae]]</div><div class="higher-taxon"><small>species</small>[[Potentilla effusa]]</div></div>
|volume=Volume 9
|mention_page=page 161, 163
|treatment_page=page 162
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Stems </b>(0.5–)1.5–4(–5.5) dm, lengths 2–3(–4) times basal leaves. <b>Basal</b> leaves pinnate, (3–)5–15(–25) cm; petiole 0.5–5(–8) cm, long hairs absent to abundant, ± appressed, 1–3 mm, stiff to weak, short and crisped hairs absent or obscured, cottony hairs abundant (at least on first-formed leaves), glands sparse or obscured; leaflets not conduplicate, lateral ones evenly to unevenly paired, 2–5(–7) per side (secondary leaflets sometimes interspersed) on distal 1/3–1/2 of leaf axis, distal pairs usually not decurrent or confluent with terminal leaflet, larger leaflets oblanceolate to narrowly obovate, 1–2.5(–3) × 0.3–1.3(–1.8) cm, distal (1/2–)2/3–3/4 (rarely more) of margin incised ± 1/2 to midvein, teeth (1–)2–9 per side, 1–4 mm, surfaces similar, gray to white or ± green, abaxial: long hairs sparse to common (at least on veins), 0.5–1.5 mm, weak to stiff, short or crisped hairs absent or sparse, sometimes obscured, cottony hairs absent or sparse to dense, glands absent, sparse, or obscured, adaxial: long hairs absent or sparse to common, short or crisped hairs absent or sparse, cottony hairs absent or sparse to abundant, glands absent or sparse. <b>Cauline</b> leaves 2–6+. <b>Inflorescences</b> 7–30-flowered. <b>Pedicels</b> 0.3–3 cm. <b>Flowers</b>: epicalyx bractlets linear to narrowly lanceolate, 1–2.5(–3) × 0.3–1 mm, 1/2–2/3 as long as sepals, abaxial vestiture often much sparser than sepals, often glabrate or glabrescent distally, straight hairs absent or sparse, cottony hairs usually abundant (at least proximally), sometimes absent or nearly so (<i></i></i>var.<i><i> rupincola</i>); hypanthium 2–6 mm diam.; sepals 3–6(–7) mm, apex long acuminate; petals 4–6.5 × 4–6 mm; filaments 1–3.5 mm, anthers 0.5–1 mm; carpels 3–15, styles 1.5–2.1 mm. <b>Achenes</b> 1.8–2.1 mm, smooth.</span><!--

-->{{Treatment/Body
|distribution=w;c North America.
|discussion=<p>Varieties 2 (2 in the flora).</p><!--
--><p>In the southern Rocky Mountains, <i>Potentilla effusa</i> is relatively distinct from <i>P. hippiana</i> both morphologically and geographically, with <i>P. effusa</i> mostly east of the Continental Divide and <i>P. hippiana</i> mostly west. In general, <i>P. hippiana</i> differs from <i>P. effusa</i> in having leaflets more evenly paired, more tightly serrate with teeth often occurring on the whole margin, and more bicolored with abaxial vestiture of crisped rather than cottony hairs. Stems of <i>P. effusa</i> have more cauline leaves on average than <i>P. hippiana</i>, and vestiture of epicalyx bractlets of <i>P. effusa</i> (as here circumscribed) is never sericeous.</p><!--
--><p>The distinction between the two species is marred by intermediate populations throughout their shared range in the northern Rocky Mountains and Great Plains. Most regional floras focused on these areas have accordingly included <i>Potentilla effusa</i> within <i>P. hippiana</i>, sometimes without infraspecific distinction. An alternate solution has been the recognition of <i>P. hippiana</i> subsp. effusa, with the subspecies further subdivided into the two varieties recognized here. The varieties themselves intergrade; <i>P. effusa</i> var. ×coloradensis (Rydberg) Th. Wolf is available for the hybrid.</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Leaflets gray to white, surfaces moderately long-hairy and moderately to densely cottony.
|[[Potentilla effusa var. effusa|Potentilla effusa var. effusa]]
|-id=key-0-1
|1
|Leaflets ± green, surfaces glabrous or sparsely to moderately long-hairy (at least on veins) and not or sparsely cottony.
|[[Potentilla effusa var. rupincola|Potentilla effusa var. rupincola]]
|}
</div></div><!--

-->{{#Taxon:
name=Potentilla effusa
|author=
|authority=Douglas ex Lehmann
|rank=species
|parent rank=section
|synonyms=Potentilla hippiana subsp. effusa;P. hippiana var. effusa
|basionyms=
|family=Rosaceae
|distribution=w;c North America.
|reference=None
|publication title=Nov. Stirp. Pug.
|publication year=1830
|special status=Endemic;Selected by author to be illustrated
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V9/V9_236.xml
|subfamily=Rosaceae subfam. Rosoideae
|tribe=Rosaceae tribe Potentilleae
|genus=Potentilla
|section=Potentilla sect. Leucophyllae
|species=Potentilla effusa
}}<!--

-->[[Category:Treatment]][[Category:Potentilla sect. Leucophyllae]]