Editing Populus sect. Populus

{{short description|Section of plants}}
{{Use dmy dates|date=September 2020}}
{{automatic taxobox
|image = Populus alba leaf.jpg
|image_caption = Leaves of ''[[Populus alba]]'', the type species of the section
|taxon = Populus sect. Populus
|authority =
|synonyms =
* ''P.'' sect. ''Leuce'' [[Jean Étienne Duby|Duby]]
|synonyms_ref=<ref>{{cite web|url=http://www.tropicos.org/Name/28301378?tab=synonyms|title=Tropicos.org|publisher=Missouri Botanical Garden|accessdate=25 February 2012}}</ref>
|subdivision_ranks = Species
|subdivision = See [[#Species|text]]
|}}

'''''Populus'' [[section (botany)|section]] ''Populus''''', of the ''[[Populus]]'' (poplar) [[genus]], includes the [[Aspen|aspen trees]] and the white poplar ''[[Populus alba]]''.<ref>{{cite web|url=http://www.fpl.fs.fed.us/documnts/TechSheets/HardwoodNA/pdf_files/popaspeneng.pdf|title=technology transfer fact sheet: ''Populus'' spp.|work=Forest Products Laboratory: R&D USDA |publisher=United States Department of Agriculture Forest Service|location=Madison, Wisconsin|accessdate=20 September 2010}}</ref> The five typical aspens are all native to cold regions with cool summers, in the north of the [[Northern Hemisphere]], extending south at high altitudes in the mountains. The White Poplar, by contrast, is native to warmer regions, with hot, dry summers.{{citation needed|date=November 2011}} These trees are all medium-sized [[deciduous]] trees ranging {{convert|15|–|30|m|ft}} tall.

All of the species in section ''Populus'' typically grow in large [[clonal colony|clonal colonies]] derived from a single seedling, and spreading by means of [[basal shoot|root suckers]]; new stems in the colony may appear at up to 30–40 metres from the previous trees. Each individual tree can live for 40–150 years above ground, but the [[root]] system of the colony is long-lived, sending up new trunks as the older trunks die off above ground, spreading about a metre per year, sometimes eventually covering many hectares. They are able to survive [[wildfire|forest fires]] because the roots are below the heat of the fire, and new sprouts can grow from the roots. One colony of American aspen (''P. tremuloides'') in Utah, given the nickname of [[Pando (Quaking Aspen)|"Pando"]], has been estimated to be 80,000 years old (disputed), making it possibly the [[list of long-living organisms|oldest living colony]] of aspens.

==Species==
Some of the species in the section are:<ref name=FOC>{{cite web | url = http://www.efloras.org/browse.aspx?flora_id=2&start_taxon_id=300251 | title = ''Populus'' Sect. ''Populus'' | work = Flora of China }}</ref>
*''[[Populus adenopoda]]'' – Chinese aspen<ref>{{GRIN | ''Populus adenopoda'' | 29357 | accessdate = 21 January 2018}}</ref> (China, south of ''P. tremula'')
*''[[Populus alba]]'' – white poplar (northwest Africa, southern Europe, east to central Asia)
*''[[Populus davidiana]]'' – Korean aspen<ref name=":0">{{Cite book|url=http://www.forest.go.kr/kna/special/download/English_Names_for_Korean_Native_Plants.pdf|title=English Names for Korean Native Plants|publisher=[[Korea National Arboretum]]|year=2015|isbn=978-89-97450-98-5|location=Pocheon|pages=585|access-date=22 December 2016|via=[[Korea Forest Service]]|url-status=dead|archiveurl=https://web.archive.org/web/20170525105020/http://www.forest.go.kr/kna/special/download/English_Names_for_Korean_Native_Plants.pdf|archivedate=25 May 2017}}</ref> (Korea)
*''[[Populus grandidentata]]'' – bigtooth aspen (eastern North America, south of ''P. tremuloides'')
*''[[Populus koreana]]'' – Korean poplar<ref name=":0" /> (Korea)
*''[[Populus ningshanica]]''
*''[[Populus qiongdaoensis]]''
*''[[Populus rotundifolia]]''
*''[[Populus sieboldii]]'' – Japanese aspen<ref>{{GRIN | ''Populus sieboldii'' | 315717 | accessdate = 21 January 2018}}</ref> (Japan)
*''[[Populus simonii]]'' – Simon's poplar<ref name=":0" /> (Korea)
*''[[Populus suaveolens]]'' – Manchurian poplar<ref name=":0" /> (Korea)
*''[[Populus tomentosa]]'', Chinese white poplar<ref>{{GRIN | ''Populus tomentosa'' | 29421 | accessdate = 21 January 2018}}</ref> (China)
*''[[Populus tremula]]'' – Eurasian aspen (northern Europe and Asia)
*''[[Populus tremuloides]]'' – American aspen (northern and western North America)
*''[[Populus wulianensis]]''

Natural hybrids between species in the section include:
*''Populus'' × ''canescens'': grey poplar,<ref>{{GRIN | ''Populus'' × ''canescens'' | 29379 | accessdate = 21 January 2018}}</ref> ''P. alba'' × ''P. tremula''
*''Populus'' × ''hopeiensis'': ''P. davidiana'' × ''P. tomentosa''
*''Populus'' × ''pseudotomentosa'': ''P. adenopoda'' × ''P. tomentosa''

==Ecology==
Aspens do not thrive very well in the shade, and it is difficult for aspen seedlings to grow in an already mature aspen stand. Fire indirectly benefits aspen trees, since it allows the saplings to flourish in open sunlight in the burned landscape. Lately, aspens have an increased popularity in forestry, mostly because of their fast growth rate and ability to regenerate from sprouts, making the [[reforestation]] after harvesting much cheaper, since no planting or [[sowing]] is required.

In contrast with many trees, aspen [[Bark (botany)|bark]] is base-rich, meaning that aspens are important hosts for [[bryophytes]]<ref>[http://www.cairngorms.co.uk/resource/docs/publications/05042007/CNPA.Paper.440.Aspen%20Report.txt The Biodiversity and Management of Aspen woodlands: Proceedings of a one-day conference held in Kingussie, Scotland, on 25th May 2001]</ref> and act as food plants for the [[larvae]] of butterfly ([[Lepidoptera]]) species—see List of Lepidoptera that feed on poplars.

Young aspen bark is an important seasonal forage for the [[european hare]] and other animals in early spring. Aspen is also a tree of choice of the [[european beaver]].

==Uses==
Aspen [[wood]] is white and soft, but fairly strong, and has low flammability. It has a number of uses, notably for making [[match]]es and [[paper]] where its low flammability makes it safer to use than most other woods. Shredded aspen wood is used for packing and stuffing, sometimes called [[excelsior (wood wool)]]. It is also a popular animal bedding, since it lacks the [[phenol]]s associated with [[pine]] and [[juniper]], which are thought to cause [[respiratory system]] ailments in some animals. Heat-treated aspen is a popular material for the interiors of a [[sauna]]. While standing trees sometimes tend to rot from the heart outward, the dry timber weathers very well, becoming silvery-grey and resistant to rotting and warping, and has traditionally been used for rural construction in the northwestern regions of Russia (especially for roofing, in the form of thin slats).

The [[Ojibwe]] used the inner bark of the trunk as a [[poultice]], and the [[Cree]] ate the inner bark in the spring as a mild purgative.<ref>Native American ethnobotany, pp. 427–433, Daniel E. Moerman 1998.</ref>

==References==
{{Reflist}}

==External links==
*[https://web.archive.org/web/20050305112933/http://www.treesforlife.org.uk/tfl.aspen_info_resource.html Aspen Information Resource, U.K.]
*[https://web.archive.org/web/20120126102319/http://www.cpluhna.nau.edu/Biota/aspen_forest.htm Quaking Aspen Forests of the Colorado Plateau]
*[http://www.cas.vanderbilt.edu/bioimages/species/pogr4.htm Bioimages: Populus grandidentata] bigtooth aspen
*[http://digitalcommons.usu.edu/aspen_bib/ Aspen Research Bibliography]

{{Taxonbar|from=Q7229840}}

[[Category:Populus]]
[[Category:Medicinal plants]]
[[Category:Plant sections]]