Populus

{{Short description|Genus of plants}}

{{Distinguish|text=Liriodendron tulipifera (tulip poplar)}}

{{About||other uses}}

{{Use dmy dates|date=September 2020}}

{{Automatic taxobox

|fossil_range= {{fossil range|58|0}}

|image = Lapo gyslos.jpeg

|image_caption = Leaf of Populus tremula

|display_parents = 2

|taxon = Populus

|authority = L.

|type_species = Populus tremula

|type_species_authority = L.

|subdivision_ranks = Sections and species

|subdivision = See text

}}

Populus is a genus of 25–30 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar ({{IPAc-en|ˈ|p|ɒ|p|l|ər}}), aspen, and cottonwood.

The western balsam poplar (P. trichocarpa) was the first tree to have its full DNA code determined by DNA sequencing, in 2006.Joint Genome Institute, [http://genome.jgi-psf.org/Poptr1_1/Poptr1_1.home.html Populus trichocarpa] {{Webarchive|url=https://web.archive.org/web/20080502200403/http://genome.jgi-psf.org/Poptr1_1/Poptr1_1.home.html |date=2 May 2008 }}

Description

File:Trembling Aspen.jpg

The genus has a large genetic diversity, and can grow from {{convert|15|-|50|m|abbr=on}} tall, with trunks up to {{convert|2.5|m|ft|abbr=on|frac=2}} in diameter.

File:Populier mannelijke bloeiwijze (Populus canadensis male inflorescences).jpg]]

The bark on young trees is smooth and white to greenish or dark gray, and often has conspicuous lenticels; on old trees, it remains smooth in some species, but becomes rough and deeply fissured in others. The shoots are stout, with (unlike in the related willows) the terminal bud present. The leaves are spirally arranged, and vary in shape from triangular to circular or (rarely) lobed, and with a long petiole; in species in the sections Populus and Aigeiros, the petioles are laterally flattened, so that breezes easily cause the leaves to wobble back and forth, giving the whole tree a "twinkling" appearance in a breeze. Leaf size is very variable even on a single tree, typically with small leaves on side shoots, and very large leaves on strong-growing lead shoots. The leaves often turn bright gold to yellow before they fall during autumn.Meikle, R. D. (1984). Willows and Poplars of Great Britain and Ireland. BSBI Handbook No. 4. {{ISBN|0-901158-07-0}}.Rushforth, K. (1999). Trees of Britain and rope. Collins {{ISBN|0-00-220013-9}}.

File:Populus (Populier zaadpluis en zaden)1.jpg

The flowers are mostly dioecious (rarely monoecious) and appear in early spring before the leaves. They are borne in long, drooping, sessile or pedunculate catkins produced from buds formed in the axils of the leaves from the previous year. The flowers are each seated in a cup-shaped disk which is borne on the base of a scale which is itself attached to the rachis of the catkin. The scales are obovate, lobed, and fringed, membranous, hairy or smooth, and usually caducous. The male flowers are without calyx or corolla, and comprise a group of four to 60 stamens inserted on a disk; filaments are short and pale yellow; anthers are oblong, purple or red, introrse, and two-celled; the cells open longitudinally. The female flower also has no calyx or corolla, and comprises a single-celled ovary seated in a cup-shaped disk. The style is short, with two to four stigmata, variously lobed, and numerous ovules. Pollination is by wind, with the female catkins lengthening considerably between pollination and maturity. The fruit is a two- to four-valved dehiscent capsule, green to reddish-brown, mature in midsummer, containing numerous minute, light-brown seeds surrounded by tufts of long, soft, white hairs aiding wind dispersal.{{cite book |last=Keeler |first=H. L. |title=Our Native Trees and How to Identify Them |publisher=Charles Scribner's Sons |year=1900 |location=New York |pages=410–412}}

Classification

File:Four Poplars in four seasons.JPG

The genus Populus has traditionally been divided into six sections on the basis of leaf and flower characters;{{cite book |author=Eckenwalder, J.E. |year=1996 |title=Biology of Populus and its implications for management and conservation |chapter=Systematics and evolution of Populus |publisher=NRC Research Press, National Research Council of Canada |location=Ottawa |editor1=R.F. Stettler |editor2=H.D. Bradshaw |editor3=P.E. Heilman |editor4=T.M. Hinckley |chapter-url=https://books.google.com/books?id=HvuTJC32C3YC&pg=PR1 |isbn=9780660165066}} this classification is followed below. Recent genetic studies have largely supported this, confirming some previously suspected reticulate evolution due to past hybridisation and introgression events between the groups. Some species (noted below) had differing relationships indicated by their nuclear DNA (paternally inherited) and chloroplast DNA sequences (maternally inherited), a clear indication of likely hybrid origin.Hamzeh, M., & Dayanandan, S. (2004). Phylogeny of Populus (Salicaceae) based on nucleotide sequences of chloroplast TRNT-TRNF region and nuclear rDNA. Amer. J. Bot. 91: 1398-1408. Available [http://www.amjbot.org/cgi/content/full/91/9/1398 online] {{Webarchive|url=https://web.archive.org/web/20080129134434/http://www.amjbot.org/cgi/content/full/91/9/1398 |date=29 January 2008 }} Hybridisation continues to be common in the genus, with several hybrids between species in different sections known.{{cite book |author=Eckenwalder, J.E. |year=2001 |title=Poplar culture in North America |chapter=Key to species and main crosses |publisher=NRC Research Press |location=Ottawa |editor1=D.I. Dickmann |editor2=J.G. Isebrands |editor3=J.E. Eckenwalder |editor4=J. Richardson |pages=325–330 |isbn=978-0-660-18145-5}} There are currently 57 accepted species in the genus."Populus L.". Plants of the World Online, Kew Science. Accessed 8 September 2021. [https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:328417-2] {{Webarchive|url=https://web.archive.org/web/20230226011502/https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:328417-2|date=26 February 2023}}

= Phylogeny =

Some of the most easily identifiable fossils of this genus belongs to Poplus wilmattae, which come from the Late Paleocene of North America about 58 million years ago.{{cite book |last1=Dickmann |first1=Donald |url=http://www.fao.org/3/a-i2670e.pdf |archive-url=https://web.archive.org/web/20160808130345/http://www.fao.org/3/a-i2670e.pdf |archive-date=2016-08-08 |url-status=live |title=Poplars and Willows in the World |last2=Kuzovkina |first2=Yulia |date=2008 |publisher=The Food and Agriculture Organization of the United Nations |isbn=978-92-5-107185-4 |page=27 |access-date=24 March 2020}} However, fossils from the Cretaceous of this genus have been found in Tibet and Heilongjiang, China.{{Cite journal |last1=Liu |first1=Xia |last2=Wang |first2=Zhaoshan |last3=Wang |first3=Wei |last4=Huang |first4=Qinqin |last5=Zeng |first5=Yanfei |last6=Jin |first6=Yu |last7=Li |first7=Honglei |last8=Du |first8=Shuhui |last9=Zhang |first9=Jianguo |date=2022 |title=Origin and evolutionary history of Populus (Salicaceae): Further insights based on time divergence and biogeographic analysis |journal=Frontiers in Plant Science |volume=13 |doi=10.3389/fpls.2022.1031087 |issn=1664-462X |pmc=9815717 |pmid=36618663 |doi-access=free }}

=Selected species=

File:PopulusNigra3.jpg in autumn]]

File:Heinolan tsaarinpoppeli.jpg ("Czar's Poplar") in Heinola, Finland]]

File:Populus lasiocarpa leaves 01 by Line1.JPG]]

  • Populus section Tacamahaca – balsam poplars (North America, Asia; cool temperate)
  • Populus angustifolia – willow-leaved poplar or narrowleaf cottonwood (central North America)
  • Populus balsamifera – Balsam poplar (northern North America) (= P. candicans, P. tacamahaca)
  • Populus cathayana – (northeast Asia)
  • Populus ciliata – (Asia)
  • Populus koreana J.Rehnder – Korean poplar (northeast Asia)
  • Populus laurifolia – laurel-leaf poplar (central Asia)
  • Populus maximowiczii A.Henry – Maximowicz' poplar, Korean poplar, Mongolian poplar, Japanese poplar (northeast Asia)
  • Populus simonii – Simon's poplar (northeast Asia)
  • Populus suaveolens Fischer – Korean poplar, Mongolian poplar, Japanese poplar (northeast Asia)
  • Populus szechuanica – Sichuan poplar (northeast Asia), placed here by nuclear DNA; cpDNA places it in sect. Aigeiros
  • Populus trichocarpa – western balsam poplar or black cottonwood (western North America)
  • Populus tristis (northeast Asia), placed here by nuclear DNA; cpDNA places it in sect. Aigeiros
  • Populus ussuriensis – Ussuri poplar (northeast Asia)
  • Populus yunnanensis – Yunnan poplar (east Asia)
  • Populus section Leucoides – necklace poplars or bigleaf poplars (eastern North America, eastern Asia; warm temperate)
  • Populus heterophylla – downy poplar (southeastern North America)
  • Populus lasiocarpa – Chinese necklace poplar (eastern Asia)
  • Populus wilsonii – Wilson's poplar (eastern Asia)
  • Populus section Turanga – subtropical poplars (southwest Asia, east Africa; subtropical to tropical)
  • Populus euphratica – Euphrates poplar (North Africa, southwest and central Asia)
  • Populus ilicifolia – Tana River poplar (East Africa)
  • Populus section Abaso – Mexican poplars (Mexico; subtropical to tropical)
  • Populus guzmanantlensis (Mexico) (may be conspecific with Populus simaroa)
  • Populus mexicana – Mexico poplar (Mexico)
  • Intersectional hybrids
  • Populus × acuminata (P. angustifolia × P. deltoides) – lanceleaf cottonwood
  • Populus Pacific albus{{Cite web |url=http://www.collinsco.com/Library/Archives/ForestrySourceJuly2009.pdf |title=A Forest in the Desert: Hybrid Poplar Plantation Feeds New Mill |access-date=3 October 2019 |archive-date=29 November 2020 |archive-url=https://web.archive.org/web/20201129201055/http://www.collinsco.com/Library/Archives/ForestrySourceJuly2009.pdf |url-status=live }} (North America)

Ecology

Poplars of the cottonwood section are often wetlands or riparian trees. The aspens are among the most important boreal broadleaf trees.

Poplars and aspens are important food plants for the larvae of a large number of Lepidoptera species. Pleurotus populinus, the aspen oyster mushroom, is found exclusively on dead wood of Populus trees in North America.

Several species of Populus in the United Kingdom and other parts of Europe have experienced heavy dieback; this is thought in part to be due to Sesia apiformis which bores into the trunk of the tree during its larval stage.{{Cite journal |last=Martin-Garcia |first=J |title=Patterns and monitoring of Sesia apiformis infestations in poplar plantations at different spatial scales |journal=Journal of Applied Entomology}}

Cultivation

File:Populus nigra-bekes.jpg

File:Poplars of Khorog City Park.JPG City Park, Gorno-Badakhshan, Tajikistan]]

Many poplars are grown as ornamental trees, with numerous cultivars used. They have the advantage of growing to a very large size at a rapid pace. Almost all poplars take root readily from cuttings or where broken branches lie on the ground (they also often have remarkable suckering abilities, and can form huge colonies from a single original tree, such as the famous Pando forest made of thousands of Populus tremuloides clones).

Trees with fastigiate (erect, columnar) branching are particularly popular, and are widely grown across Europe and southwest Asia. However, like willows, poplars have very vigorous and invasive root systems stretching up to {{convert|40|m}} from the trees; planting close to houses or ceramic water pipes may result in damaged foundations and cracked walls and pipes due to their search for moisture.

A simple, reproducible, high-frequency micropropagation protocol in eastern cottonwood Populus deltoides has been reported by Yadav et al. 2009.{{cite journal |doi=10.1007/s11816-009-0088-5 |volume=3 |issue=3 |title=High frequency direct plant regeneration from leaf, internode, and root segments of Eastern Cottonwood (Populus deltoides) |year=2009 |journal=Plant Biotechnology Reports |pages=175–182 |last1=Yadav |first1=Rakesh |bibcode=2009PBioR...3..175Y |s2cid=42796629}}

=India=

File:KDJHPOP.JPG

In India, the poplar is grown commercially by farmers, mainly in the Punjab region. Common poplar varieties are:

  • G48 (grown in the plains of Punjab, Haryana, UP)
  • w22 (grown in mountainous regions, e.g., Himachal Pradesh, Pathankot, Jammu)

The trees are grown from kalam or cuttings, harvested annually in January and February, and commercially available up to 15{{nbsp}}November.

Poplars are most commonly used to make plywood: Yamuna Nagar in Haryana state has a large plywood industry reliant upon poplar. It is graded according to sizes known as "over" (over {{convert|24|in}}), "under" ({{convert|18|–|24|in}}), and "sokta" (less than {{convert|18|in}}).

=Pakistan=

In Pakistan, poplar is grown on a commercial level by farmers in Punjab, Sindh, and Khyber Pakhtunkhwa Provinces. However, all varieties are seriously susceptible to termite attack, causing significant losses to poplar every year. Logs of poplar are therefore also used as bait in termite traps for biocontrol of termites in crops.

Uses

File:Pamirihouse.JPG house]]

Although the wood from Populus is known as poplar wood, a common high-quality hardwood "poplar" with a greenish colour is actually from an unrelated genus Liriodendron. Populus wood is a lighter, more porous material.

Its flexibility and close grain make it suitable for a number of applications, similar to those of willow. The Greeks and Etruscans made shields of poplar, and Pliny the Elder also recommended poplar for this purpose.{{cite book |author=H. A. Shapiro |title=The Cambridge Companion to Archaic Greece |url=https://books.google.com/books?id=6LUcuGdJF30C&pg=PA69 |year=2007 |publisher=Cambridge University Press |isbn=978-1-139-82699-0 |page=69 |access-date=22 November 2015 |archive-date=17 July 2023 |archive-url=https://web.archive.org/web/20230717125102/https://books.google.com/books?id=6LUcuGdJF30C&pg=PA69 |url-status=live }} Poplar continued to be used for shield construction through the Middle Ages and was renowned for a durability similar to that of oak, but with a substantial reduction in weight.

=Food=

In addition to the foliage and other parts of Populus species being consumed by animals, the starchy sap layer (underneath the outer bark) is edible to humans, both raw and cooked.{{Cite book |last=Angier |first=Bradford |url=https://archive.org/details/fieldguidetoedib00angi/page/172/mode/2up |title=Field Guide to Edible Wild Plants |publisher=Stackpole Books |year=1974 |isbn=0-8117-0616-8 |location=Harrisburg, PA |pages=172 |oclc=799792 |author-link=Bradford Angier}}

=Manufacturing=

  • Guitar production,mainly used with cheaper import guitars
  • In many areas, fast-growing hybrid poplars are grown on plantations for pulpwood
  • Poplar is widely used for the manufacture of paper.[http://www.peupliersdefrance.org/indexGB.htm/ Poplar cultivation in Europe] {{webarchive|url=https://web.archive.org/web/20071103142348/http://www.peupliersdefrance.org/indexGB.htm |date=3 November 2007 }}
  • It is also sold as inexpensive hardwood timber, used for pallets and cheap plywood; more specialised uses including matches and matchboxes and the boxes for Camembert cheese.
  • Poplar wood is also widely used in the snowboard industry for the snowboard core, because it has exceptional flexibility, and is sometimes used in the bodies of electric guitars and drums.
  • Poplar wood, particularly when seasoned, makes a good hearth for a bow drill.
  • Because of its high tannic acid content, the bark has been used in Europe for tanning leather.
  • Poplar wood can be used to produce chopsticks or wooden shoes.
  • Baking moulds from peeled poplar may be used in the freezer, oven, or microwave oven.{{cite journal |last1=Aiken |first1=Laura |title=Baking Bread Abroad |journal=Bakers Journal |date=18 April 2012 |url=http://www.bakersjournal.com/news/breaking-bread-abroad-3747 |access-date=11 June 2016 |archive-date=8 August 2016 |archive-url=https://web.archive.org/web/20160808104752/http://www.bakersjournal.com/news/breaking-bread-abroad-3747 |url-status=live }}

=Energy=

Interest exists in using poplar as an energy crop for biomass, in energy forestry systems, particularly in light of its high energy-in to energy-out ratio, large carbon mitigation potential, and fast growth.

File:Rotor poplar and willow cuttings planter, planting a new nursery of poplar for biomass with short rotation..JPG

In the United Kingdom, poplar (as with fellow energy crop willow) is typically grown in a short rotation coppice system for two to five years (with single or multiple stems), then harvested and burned - the yield of some varieties can be as high as 12 oven-dry tonnes per hectare every year.{{cite journal |title=Yield and spatial supply of bioenergy poplar and willow short-rotation coppice in the UK |journal=New Phytologist |volume=178 |issue=2 fvhc |pages=358–370 |year=2008 |doi=10.1111/j.1469-8137.2008.02396.x |author=Aylott, Matthew J. |pmid=18331429 |last2=Casella |first2=E |last3=Tubby |first3=I |last4=Street |first4=NR |last5=Smith |first5=P |last6=Taylor |first6=G |s2cid=35494995|doi-access=free |bibcode=2008NewPh.178..358A }}

In warmer regions like Italy this crop can produce up to 13.8, 16.4 oven-dry tonnes of biomass per hectare every year for biannual and triennial cutting cycles also showing a positive energy balance and a high energy efficiency.{{cite journal |last1=Nassi |last2=Di Nasso |first2=N. |last3=Guidi |first3=W. |last4=Ragaglini |first4=G. |last5=Tozzini |first5=C. |last6=Bonari |first6=E. |year=2010 |title=Biomass production and energy balance of a twelve-year-old short-rotation coppice poplar stand under different cutting cycles |doi=10.1111/j.1757-1707.2010.01043.x |journal=Global Change Biology Bioenergy |volume=2 |issue=2 |pages=89–97 |s2cid=86414864}}

=Fuel=

Biofuel is another option for using poplar as bioenergy supply. In the United States, scientists studied converting short rotation coppice poplar into sugars for biofuel (e.g. ethanol) production.{{cite journal |title=Can we use short rotation coppice poplar for sugar based biorefinery feedstock? Bioconversion of two-year-old poplar grown as short rotation coppice |journal=Biotechnology for Biofuels |volume=10 |issue=1 |page=144 |year=2017 |doi=10.1186/s13068-017-0829-6 |pmid=28592993 |pmc=5460468 |author1=Dou, C |author2=Marcondes, W. |author3=Djaja, J. |author4=Renata, R. |author5=Gustafson, R. |doi-access=free |bibcode=2017BB.....10..144D }}

Considering the relative cheap price, the process of making biofuel from SRC can be economically feasible, although the conversion yield from short rotation coppice (as juvenile crops) were lower than regular mature wood. Besides biochemical conversion, thermochemical conversion (e.g. fast pyrolysis) was also studied for making biofuel from short rotation coppice poplar and was found to have higher energy recovery than that from bioconversion.{{cite journal |title=Fast pyrolysis of short rotation coppice poplar: an investigation in thermochemical conversion of a realistic feedstock for the biorefinery |journal=Biotechnology for Biofuels |volume=10 |issue=1 |page=144 |year=2017 |doi=10.1021/acssuschemeng.7b01000 |author1=Dou, C |author2=Chandler, D. |author3=Resende, F. |author4=Renata, R.}}

=Art=

Poplar was the most common wood used in Italy for panel paintings; the Mona Lisa and most famous early Italian Renaissance paintings are on poplar.{{Cite journal |last1=Uzielli |first1=Luca |last2=Gril |first2=Joseph |last3=Cocchi |first3=Linda |last4=Colmars |first4=Julien |last5=Dionisi Vici |first5=Paolo |last6=Dureisseix |first6=David |last7=Goli |first7=Giacomo |last8=Jullien |first8=Delphine |last9=Marcon |first9=Bertrand |last10=Mazzanti |first10=Paola |last11=Remond |first11=Romain |date=July 2011 |title=Experimental studies on the wooden support of the "Mona Lisa" |url=https://hal.science/hal-00945958#:~:text=The%20%E2%80%9CMona%20Lisa%E2%80%9D%20(Louvre,Poplar%20(Populus%20alba%20L.) |journal=The Safeguard of Cultural Heritage. A Challenge from the Past for the Europe of Tomorrow. COST Strategic Workshop |series=The safeguard of cultural heritage : a challenge from the past for the Europe for the Europe of tomorrow |location=Florence, Italy |publisher=Firenze University Press |pages=367 p |doi=10.13140/2.1.1021.1525}} The wood is generally white, often with a slightly yellowish colour.

Some stringed instruments are made with one-piece poplar backs; violas made in this fashion are said{{citation needed|date=July 2011}} to have a particularly resonant tone. Similarly, though typically it is considered to have a less attractive grain than the traditional sitka spruce, poplar is beginning to be targeted by some harp luthiers as a sustainable and even superior alternative for their sound boards:{{cite web |url=http://traditionalharps.com/Old_Rees_Harps_Site/HarpsGeneralTonewoods.html |title=Harps by Wm. Rees - WM REES HARP MYTH 8 |access-date=2011-07-01 |url-status=dead |archive-url=https://web.archive.org/web/20120326111406/http://traditionalharps.com/Old_Rees_Harps_Site/HarpsGeneralTonewoods.html |archive-date=26 March 2012}} Rees Harps Website, "Harp Myth #8". in these cases another hardwood veneer is sometimes applied to the resonant poplar base both for cosmetic reasons, and supposedly to fine-tune the acoustic properties.

=Land management=

Lombardy poplars are frequently used as a windbreak around agricultural fields to protect against wind erosion.

=Agriculture=

Logs from the poplar provide a growing medium for shiitake mushrooms.[http://www.mtg.unimelb.edu.au/Shiitake.htm Shiitake growth studies performed by RMIT] {{webarchive|url=https://web.archive.org/web/20100103221747/http://www.mtg.unimelb.edu.au/Shiitake.htm |date=3 January 2010 }}

=Phytoremediation=

Poplar represents a suitable candidate for phytoremediation since it has the ability to remove and store harmful pollutants in its trunk while also removing air pollution.{{Cite journal |last1=Doty |first1=Sharon L. |last2=Freeman |first2=John L. |last3=Cohu |first3=Christopher M. |last4=Burken |first4=Joel G. |last5=Firrincieli |first5=Andrea |last6=Simon |first6=Andrew |last7=Khan |first7=Zareen |last8=Isebrands |first8=J. G. |last9=Lukas |first9=Joseph |last10=Blaylock |first10=Michael J. |date=2017-09-05 |title=Enhanced Degradation of TCE on a Superfund Site Using Endophyte-Assisted Poplar Tree Phytoremediation |url=https://pubs.acs.org/doi/10.1021/acs.est.7b01504 |journal=Environmental Science & Technology |language=en |volume=51 |issue=17 |pages=10050–10058 |doi=10.1021/acs.est.7b01504 |pmid=28737929 |bibcode=2017EnST...5110050D |issn=0013-936X}} This plant has been successfully used to target many types of pollutants including trace element (TEs) in soil{{cite journal |last1=Guidi Nissim |first1=W. |last2=Palm |first2=E. |last3=Mancuso |first3=S. |last4=Azzarello |first4=E. |year=2018 |title=Trace element phytoextraction from contaminated soil: a case study under Mediterranean climate |journal=Environmental Science and Pollution Research |volume=25 |issue=9 |pages=9114–9131 |doi=10.1007/s11356-018-1197-x |pmid=29340860 |bibcode=2018ESPR...25.9114G |s2cid=3892759}} and sewage sludge,Werther Guidi Nissim, Alessandra Cincinelli, Tania Martellini, Laura Alvisi, Emily Palm, Stefano Mancuso, Elisa Azzarello, Phytoremediation of sewage sludge contaminated by trace elements and organic compounds, Environmental Research, Volume 164, July 2018, Pages 356-366, ISSN 0013-9351, https://doi.org/10.1016/j.envres.2018.03.009., landfill leachate{{cite journal |last1=Justin |first1=MZ |last2=Pajk |first2=N |last3=Zupanc |first3=V |last4=Zupanƒçiƒç |first4=M |year=2010 |title=Phytoremediation of landfill leachate and compost wastewater by irrigation of Populus and Salix: Biomass and growth response |journal=Waste Management |volume=30 |issue=6 |pages=1032–42 |doi=10.1016/j.wasman.2010.02.013 |pmid=20211551|bibcode=2010WaMan..30.1032J }} Polychlorinated Biphenyl (PCBs),Meggo RE, Schnoor JL. Cleaning Polychlorinated Biphenyl (PCB) Contaminated Garden Soil by Phytoremediation. Environmental sciences. 2013;1(1):33-52 Trichloroethylene (TCE),{{cite journal |last1=Gordon |first1=M |last2=Choe |first2=N |last3=Duffy |first3=J |display-authors=etal |year=1998 |title=Phytoremediation of trichloroethylene with hybrid poplars |journal=Environmental Health Perspectives |volume=106 |issue=Suppl 4 |pages=1001–1004 |doi=10.2307/3434144 |pmc=1533336 |jstor=3434144 |pmid=9703485}} Polycyclic Aromatic Hydrocarbon (PAHs).{{cite journal |last1=Spriggs |first1=T. |last2=Banks |first2=M. K. |last3=Schwab |first3=P. |year=2005 |title=Phytoremediation of Polycyclic Aromatic Hydrocarbons in Manufactured Gas Plant–Impacted Soil |journal=J. Environ. Qual. |volume=34 |issue=5 |pages=1755–1762 |doi=10.2134/jeq2004.0399 |pmid=16151227|bibcode=2005JEnvQ..34.1755S }}

Culture

Two notable poems in English lament the cutting down of poplars, William Cowper's "The Poplar Field" and Gerard Manley Hopkins' "Binsey Poplars felled 1879".

In Billie Holiday's "Strange Fruit", she sings "Black bodies swinging in the southern breeze/Strange fruit hanging from the poplar trees…".

The Odd Poplars Alley, in Iași, Romania, is one of the spots where Mihai Eminescu sought inspiration in his works (the poem "Down Where the Lonely Poplars Grow"). In 1973, the 15 white poplars still left (with age ranges between 233 and 371 years) were declared natural monuments.{{cite web |date=2017-10-17 |title=Iași - the county of centuries-old trees |url=http://www.agerpres.ro/engleza-destinatie-romania/2014/09/04/destination-romania-iasi-the-county-of-centuries-old-trees-13-57-22 |access-date=2018-10-15 |publisher=Agerpres.ro |archive-date=6 August 2019 |archive-url=https://web.archive.org/web/20190806074723/https://www.agerpres.ro/engleza-destinatie-romania/2014/09/04/destination-romania-iasi-the-county-of-centuries-old-trees-13-57-22 |url-status=dead }}

In Ukraine, one of neighborhoods of Kyiv is named after Populus nigra as Osokorky, a local name.

In Greek mythology, the Heliades were turned into poplar trees by the gods when their brother, Paethon, died after attempting to drive his father, Helios, his chariot across the sky.

References

{{Reflist}}