Populus nigra (black poplar)
- Summary of Invasiveness
- Taxonomic Tree
- Notes on Taxonomy and Nomenclature
- Plant Type
- Distribution Table
- History of Introduction and Spread
- Risk of Introduction
- Habitat List
- Hosts/Species Affected
- Biology and Ecology
- Latitude/Altitude Ranges
- Air Temperature
- Rainfall Regime
- Soil Tolerances
- Natural enemies
- Means of Movement and Dispersal
- Pathway Causes
- Pathway Vectors
- Economic Impact
- Environmental Impact
- Threatened Species
- Social Impact
- Risk and Impact Factors
- Uses List
- Wood Products
- Similarities to Other Species/Conditions
- Prevention and Control
- Distribution Maps
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PicturesTop of page
IdentityTop of page
Preferred Scientific Name
- Populus nigra L.
Preferred Common Name
- black poplar
- Populus nigra var. betulifolia (Pursh) Torr.
- Populus nigra var. caudina
- Populus nigra var. italica (Moench.) Koehne
- Populus nigra var. pubescens
- Populus nigra var. thaysiana
- Populus nigra var. thevestina (Dode) Bean
- Populus nigra var. vistulensis
Other Scientific Names
- Populus croatica Waldst. & Kit. ex Besser
- Populus italica (Munchh.) Moench
- Populus nigra subsp. pyramidalis (Rozan.) Cel.
- Populus nigra var. pyramidalis (Rozan.) Spach
- Populus pannonica Kit ex Besser
- Populus sinensis (Carriere) Dode
International Common Names
- English: Lombardy poplar
- Spanish: álamo negro; chopo negro
- French: peuplier d'Italie; peuplier noir
Local Common Names
- Croatia: crne topole
- Germany: Pyramiden- Pappel; Scharwzpappel; Schwarz- Pappel
- Italy: pioppo italiano; pioppo nero
- Japan: seiyo-kako-yanagi
- Netherlands: Italiaanse populier
- Sweden: poppel, svart-
- Turkey: karakavak
- POPNI (Populus nigra)
Summary of InvasivenessTop of page
P. nigra is a fast-growing tree utilized for afforestation and as an ornamental in all the temperate areas of the world. As an endemic species, P. nigra can be considered on the verge of extinction in a large part of its natural range, particularly in west and central Europe, because its natural habitat is gradually being reduced by human activity and because it easily hybridizes with other species (especially P. x canadensis) and with its fastigiate form var. italica (Lombardy poplar).
It is the latter, P. nigra var. italica, which is considered an invasive or potentially invasive species in some parts of the world, including North America, South Africa and Argentina. It is considered an invasive species in very localized areas in the USA, notably around the Great Lakes region and particularly in Michigan, where it was originally planted for dune stabilization. This has led to the disruption of natural dune migration with concomitant impacts on natural habitats and biodiversity. However, as a male clone it produces no seeds so invasive spread is limited and effected by profuse suckering. Its invasiveness is also aided by cultivation as an ornamental, windbreak and landscape tree.
Taxonomic TreeTop of page
- Domain: Eukaryota
- Kingdom: Plantae
- Phylum: Spermatophyta
- Subphylum: Angiospermae
- Class: Dicotyledonae
- Order: Salicales
- Family: Salicaceae
- Genus: Populus
- Species: Populus nigra
Notes on Taxonomy and NomenclatureTop of page
A wide natural range and the cultivation of Populus nigra over the past centuries makes the taxonomy of the species particularly complex. There are many intermediate forms arising from spontaneous hybridization among varieties which are difficult to classify in an unequivocal way (Cagelli and Lefevre, 1995; Beringen, 1998). The classification of Asiatic varieties is still under discussion. A classification has been proposed in a review by Zsuffa (1974).
In the past, the characterization of the species was largely based on morphological features, but now molecular genetic techniques allow better discrimination of species and hybrids and probably a new and more accurate classification will be possible (Vackova et al., 1998; Heinze, 1998; Sanchez et al., 1998).
DescriptionTop of page
P. nigra var. italica is a deciduous tree, with a narrow columnar crown. The trunk is straight with suckers at the base. The root system is lateral, shallow or deep, depending on soil layer and depth of water table, and can be invasive and problematical if trees are planted near buildings. The bark is more or less dark brown, thin and easily damaged.
Lombardy poplar trees are best known for their columnar (fastigiate) form and unusual vertical branching structure; branches start close to the ground and grow parallel to the trunk. Trees grow rapidly, maybe up to 1.8 m per year; they attain a final height of 12-16 m with a spread of 3-4.5 m (Beaulieu, 2015).
The leaves are rhombic, long-acuminate, the lateral edge rounded and finely crenate, not ciliate, glabrous and lighter green beneath; leaves of long shoots are 4-8 cm wide and 5-8 cm long, cuneate at the base. The leaves of shorter shoots are smaller and more or less rhomboid. Petioles are thin and flat. Leaves turn yellow in autumn.
As a male clone, P. nigra var. italica only produces staminate catkins, which are usually reddish, 4-6 cm long with 20-30 stamens.
Plant TypeTop of page Broadleaved
DistributionTop of page
The natural distribution of P. nigra ranges from western, central and southern Europe to West and Central Asia, reaching the Yenisei River in Siberia. It is also found in isolated localities in North Africa (FAO, 1980; Allegri, 1971).
The ornamental P. nigra var. italica originated as a single fastigiate tree in Lombardy in northern Italy in the 18th century and has been widely introduced for use as windbreaks, screens, avenue trees and landscape plantings. It can be found along roads and in parks all over the temperate regions of the world (Europe, North and South America, South Africa, Australia, New Zealand and China). It has also been introduced into subtropical environments where it performs poorly.
Distribution TableTop of page
The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.
|Continent/Country/Region||Distribution||Last Reported||Origin||First Reported||Invasive||Planted||Reference||Notes|
|Georgia (Republic of)||Present||Planted, Natural|
|-Jammu and Kashmir||Present||Planted|
|Japan||Present||Present based on regional distribution.|
|Canada||Present||Present based on regional distribution.|
|USA||Present||Present based on regional distribution.|
|Brazil||Present||Present based on regional distribution.|
|Russian Federation||Present||Present based on regional distribution.|
History of Introduction and SpreadTop of page
P. nigra var. italica was disseminated throughout Europe in the mid-18th century from Italy, where it was found growing on the banks of the River Po in Lombardy (Wood, 1994). Augustine Henry found evidence that it originated there between 1700 and 1720 and was rapidly spread worldwide by cuttings, reaching France in 1749, England in 1758 and North America in 1784 (Henry, 1914). It was soon widely planted in Europe as an avenue tree, as an ornamental and, for a time, for its timber. In the USA, it now occurs in all the 48 contiguous states except Idaho and Montana, as well as in several eastern and western Canadian provinces (USDA-NRCS, 2015). In colonial times, it was introduced as an ornamental to Chile and Argentina.
Some negative effects of growing Lombardy poplar have been identified in recent years, particularly in terms of impact on native vegetation, leading to its classification as a localized invasive species, for example, in southern US forest and grassland systems (University of Georgia, 2009; Miller et al., 2010), in North Dakota and in Michigan (Invasive Plant Atlas of the United States, 2014). In the Upper Midwest it is classed as an invasiveness category 2 species, that is, a lesser invader of natural areas (Czarapata, 2005).
Risk of IntroductionTop of page
Lombardy poplar is still widely planted as an ornamental and landscape tree.
HabitatTop of page
P. nigra var. italica prefers to grow in full sun on well-drained, acid, neutral or alkaline soils. They tolerate wet soil but can also grow well under drought, losing leaves early in very dry summers (Gilman and Watson, 1994).
Habitat ListTop of page
|Terrestrial – Managed||Managed forests, plantations and orchards||Principal habitat||Productive/non-natural|
|Rail / roadsides||Principal habitat||Productive/non-natural|
|Urban / peri-urban areas||Principal habitat||Harmful (pest or invasive)|
|Urban / peri-urban areas||Principal habitat||Productive/non-natural|
|Terrestrial ‑ Natural / Semi-natural||Riverbanks||Principal habitat||Productive/non-natural|
|Coastal dunes||Principal habitat||Harmful (pest or invasive)|
|Coastal dunes||Principal habitat||Productive/non-natural|
Hosts/Species AffectedTop of page
In the USA, P. nigra var. italica is known to affect the threatened native plant species Cirsium pitcheri in the Great Lakes open dune systems, while in Argentina’s Patagonia its hybrids are replacing native Salix humboldtiana in riparian habitats.
Biology and EcologyTop of page
P. nigra var. italica is diploid with 2n=38 chromosomes (Dickman and Kuzovkina, 2008).
As Lombardy poplar (P. nigra. var. italica) is a natural male clone, it produces no seed. Its pollen, however, allows gene flow and intraspecific and interspecific hybridization to occur.
Physiology and Phenology
Flowering of male flowers begins when trees are 4-10 years old and occurs in early spring, before full leaf emergence. The roots are very vigorous and invasive, and can destroy land drainage systems and damage foundations.
P. nigra trees live for 200-300 years, but var. italica is much more short-lived, being susceptible to damage from a range of pests and diseases which disfigure the tree, cause branch drop and lead to eventual mortality, often succumbing within 15 years, but more often 30-50 years. Older trees become more and more susceptible to being blown over in strong winds. This rapid decline has made them unpopular nowadays with landscaping professionals (Beaulieu, 2015).
P. nigra var. italica grows in temperate zones with a bimodal rainfall regime. To perform well it needs an average of 700 mm of rain per year, distributed in spring and autumn, and it can tolerate dry summers. In general, there is a relationship between summer temperatures and growth in locations with adequate supplies of soil moisture. In areas with heavy rainfall, it performs poorly. It can grow on chalk, sand, clay or loam soils of acid, neutral or alkaline pH.
Latitude/Altitude RangesTop of page
|Latitude North (°N)||Latitude South (°S)||Altitude Lower (m)||Altitude Upper (m)|
Air TemperatureTop of page
|Parameter||Lower limit||Upper limit|
|Absolute minimum temperature (ºC)||-29|
|Mean annual temperature (ºC)||9||17|
|Mean maximum temperature of hottest month (ºC)||18||31|
|Mean minimum temperature of coldest month (ºC)||-5||12|
RainfallTop of page
|Parameter||Lower limit||Upper limit||Description|
|Dry season duration||2||3||number of consecutive months with <40 mm rainfall|
|Mean annual rainfall||300||1000||mm; lower/upper limits|
Rainfall RegimeTop of page Bimodal
Soil TolerancesTop of page
Special soil tolerances
Natural enemiesTop of page
|Natural enemy||Type||Life stages||Specificity||References||Biological control in||Biological control on|
|Cossus cossus||Herbivore||Stems||not specific|
|Cryptodiaporthe populea||Pathogen||Growing point/Stems||not specific|
|Cryptorhynchus lapathi||Herbivore||Stems||not specific|
|Drepanopeziza populorum||Pathogen||Leaves||to genus|
|Melampsora laricis-populina||Pathogen||Leaves||to genus|
|Paranthrene dollii||Herbivore||Stems||not specific|
|Plagiodera versicolora||Herbivore||Leaves||not specific|
|Saperda carcharias||Herbivore||Leaves/Stems||not specific|
|Venturia populina||Pathogen||Growing point/Leaves||to genus|
Means of Movement and DispersalTop of page
As P. nigra var. italica produces no seed, its main means of natural dispersal is by vigorous suckering.
Lombardy poplar, although not as popular as previously, is still widely planted as an ornamental and landscape tree.
Pathway CausesTop of page
Pathway VectorsTop of page
|Plants or parts of plants||Yes||Yes|
Economic ImpactTop of page
P. nigra var. italica is a fast growing tree, grown in nurseries and utilized as an ornamental in all the temperate areas of the world.
Environmental ImpactTop of page
Impact on Habitats
P. nigra var. italica is seen as a one of 27 emerging alien invasives of the alpine habitat of the Drakensberg Alpine Centre in southern Africa (South Africa, Lesotho), an area which supports some 334 endemic and 595 near-endemic angiosperm species (Carbutt, 2012). In Michigan, USA, it and other non-native species were originally introduced as a result of residential development in the dune systems around the Great Lakes. This led to dune stabilization and the disruption of natural dune migration, with subsequent impacts on natural dune habitats and biodiversity (Albert, 1999).
Impact on Biodiversity
One of the species negatively affected in the Great Lakes dune systems by the presence of P. nigra var. italica is Cirsium pitcheri (Pitcher’s thistle), listed by the US Fish and Wildlife Service as a threatened species. In a study by the US Forest Service Manistee National Forest in Michigan, for example, the most prevalent invasive species identified were spotted knapweed (Centaurea maculosa) and Lombardy poplar (US Fish and Wildlife Service, 2006b). Although the poplar’s effects on C. pitcheri habitat are unknown, thistle numbers were lower at sites with poplar compared to sites without. Although herbicide use is not permitted in these habitats, this restriction was partially lifted in the case of Lombardy poplar (US Fish and Wildlife Service, 2006a), as cutting down trees with chainsaws and pruning the new growth was shown to result in aggressive regrowth and the spread of suckers (O’Connell and Stephens, 2002).
In Eurasia P. nigra var. italica hybridizes as a male parent with native black poplars, thus contaminating the gene pools of threatened P. nigra populations.
In the Patagonia region of Argentina, non-native Salicaceae species, mainly Salix but also Populus taxa derived from crosses between P. nigra var. italica and other invasive poplars such as P. deltoides and P. x canadensis, are invading floodplains, displacing native tree species such as the native willow S. humboldtiana due to their more vigorous vegetative reproduction capacity (Thomas et al., 2012).
Threatened SpeciesTop of page
Social ImpactTop of page
When grown in urban areas, the roots of P. nigra var. italica can damage or destroy land drainage systems and affect building foundations.
Risk and Impact FactorsTop of page Invasiveness
- Proved invasive outside its native range
- Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
- Benefits from human association (i.e. it is a human commensal)
- Fast growing
- Reproduces asexually
- Altered trophic level
- Ecosystem change/ habitat alteration
- Infrastructure damage
- Reduced native biodiversity
- Threat to/ loss of endangered species
- Threat to/ loss of native species
- Highly likely to be transported internationally deliberately
- Difficult/costly to control
UsesTop of page
Natural stands of P. nigra produce low quality wood which is suitable only for local and artisan use. Plantations offer the advantage of greater wood homogeneity. The main uses are for plywood, semi-finished products for carpentry, sawn wood, packaging, pallets, wood-wool, fibreboards, particleboards and veneers (Bohme et al., 1983; Giordano, 1980). The wood is also used to make charcoal. However, the wood from var. italica has always been considered of worse quality than that of other poplars (Society for the Diffusion of Useful Knowledge, 1829). It is among the lightest of timbers, and used in making packing cases. Although soft, it will bear some strain without breaking. Historically in Lombardy the wood was used to make crates for grapes up until the early 19th century.
Lombardy poplars are grown for decorative, shade and windbreak purposes in urban areas and in landscapes.
The compact crown and fastigiate form of P. nigra var. italica make it particularly suitable for use in windbreaks and shelterbelts (Peri, 1998). It is planted as a single or double line to protect orchards and horticultural crops from winds and to reduce wind erosion of cultivated soil. It is also used to control erosion along riverbanks and roadbeds (Tatsumi, 1973; Matthei, 1997).
Uses ListTop of page
Animal feed, fodder, forage
- Fodder/animal feed
- Boundary, barrier or support
- Shade and shelter
- Carved material
- Miscellaneous materials
- Source of medicine/pharmaceutical
Wood ProductsTop of page
- Short-fibre pulp
- Building poles
Sawn or hewn building timbers
- Carpentry/joinery (exterior/interior)
- For light construction
- Wall panelling
- Improved wood
- Wood cement
- Industrial and domestic woodware
- Sports equipment
Similarities to Other Species/ConditionsTop of page
Its columnar habit makes P. nigra var. italica very distinctive in the landscape. Apart from its habit, var. italica is a typical P. nigra in all its other characteristics.
Prevention and ControlTop of page
Methods advocated in Canada for Lombardy poplar control by the Canadian Botanical Conservation Network (2015) include (1) girdling the tree to remove bark and phloem layer from a 10 cm band around the trunk and (2) cutting stems and applying herbicide, but this does not always eliminate suckering. Monitoring and retreatment of sites is always necessary. In Michigan’s dune system, cutting down trees with chainsaws and pruning the new growth resulted in aggressive growth and the spread of suckers and had to be supplemented with judicious use of herbicides (O’Connell and Stephens, 2002; US Fish and Wildlife Service, 2006a).
ReferencesTop of page
Alba I; Frison G, 1993. Prove sperimentali sulla coltivazione del vivaio di pioppo in Turchia. Linea Ecologica Economia Montana XXV, 5:50-57.
Albert DA, 1999. Natural community abstract for open dunes. Lansing, MI, USA: Michigan Natural Features Inventory, 6 pp. http://mnfi.anr.msu.edu/abstracts/ecology/Open_dunes.pdf
Allegro G; Picco F, 1992. Poplar clonal preferences of the Fall webworm (Hyphantria cunea Drury). Proc. XIV Sess. Zaragoza, Spain: FAO/IPC, 1:394-400.
Arbez M; Lefèvre F, 1997. The European forest genetics resource programme. Objectives and general concept. A case study concerning the black poplar (Populus nigra L:). Bocconea, 7:389-398.
Avanzo E; Bisoffi S; Gras MA; Mughini G, 1985. Breeding strategies adopted in Italy for poplars of the Aigeiros Section. Genetica Agraria, 39:308.
Beaulieu D, 2015. Lombardy poplar trees: is planting this traditional windbreak now a no-no?. http://landscaping.about.com/od/landscapedesignprivacy/p/lombardy_poplar.htm
Bohme P; Lorenz U; Wagenfuhr R, 1983. On the international state of the manufacture and processing of thin veneers. [Zum internationalen Stand der Herstellung und Verarbeitung dunner Furniere.] Holztechnologie, 24(1):39-42; BLL; 29 ref.
Canadian Botanical Conservation Network, 2015. Invasive tree species. http://www.rbg.ca/archive/cbcn/en/projects/invasives/i_tree2.html
Colorio G; Beni C; Facciotto G; Allegro G; Frison G, 1996. The effect of site preparation method on the growth and health of poplar. Informatore Agrario, 52(22):51-57.
Cooper F, 2006. The black poplar: ecology, history and conservation. Oxford, UK: Windgather Press/Oxbow Books.
Dahab AMA; Shafiq Y; Al Kinany A; Yahya MD, 1975. Effect of seasonal variations in root formation and growth of cuttings of different trees and shrubs. Mesopotamia Journal of Agriculture, 10(1-2):3-12.
Dickman DI; Kuzovkina J, 2008. International Poplar Commission thematic papers: Poplars and willows in the world. Chapter 2. Poplars and willows of the world, with emphasis on silviculturally important species. Rome, Italy: FAO, 134 pp. [ FAO Working Paper IPC/9-2.]
FAO, 1980. Poplars and willows. Rome, Italy: FAO Forestry series 10.
Frison G; Facciotto G, 1985. Effects of characteristics of cuttings on the establishment of poplar nurseries. [Importanza delle caratteristiche delle talee per la costituzione del vivaio di pioppo.] Quaderni di Ricerca, Centro di Sperimentazione Agricola e Forestale Istituto di Sperimentazione per la Pioppicoltura, Italy, No. 6, 21pp.; 14 ref.
Gadirca V, 1998. Ecogeographic variability of Populus nigra L. in Moldova and the former USSR. In: Populus nigra network. Report of the fourth meeting, 3-5 October 1997, Geraardsbergen, Belgium. International Plant Genetic Resources Institute, Rome, Italy, 24-26.
Gambi G; Hippoliti G; Pierguidi A, 1989. Veneer 'pipes' as containers for production of tree seedlings. ['Tubi' di sfogliati di legno come contenitori per la produzione di piantine forestali.] Monti e Boschi, 40(2):22-25; 1 ref.
Gilman EF; Watson DG, 1994. Populus nigra 'Italica', Lombardy poplar. Florida Cooperative Extension Service Fact Sheet, ST-501. Gainesville, FL, USA: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, 3 pp, 3 pp.
Giorcelli A; Allegro G, 1998. I trattamenti per una corretta difesa fitosanitaria del vivaio di pioppo. Sherwood-Foreste ed Alberi Oggi, 4(9):31-37.
Giordano G, 1980. I legnami del Mondo. II edition. Ed. Il Cerilo Editrice Roma, Italy, 191-193.
Heinze B, 1998. PRC-based chloroplast DNA assays for the identification of native Populus nigra and introduced poplar hybrids in Europe. Forest Genetics, 5(1):31-38.
Henry A, 1914. The black poplars. Gardeners' Chronicle, 56:1-2, 46-47.
Herpka I, 1986. A survey on development and possibilities of growing natural forest of poplars and willows. In: Poplar Res. Inst. (ed). Poplar and Willows, Novi Sad Yugoslavia, 21-36.
IBPGR/FAO, 1993. European Forest Genetics Resources Programme "EUFORGEN", Rome, Italy.
Invasive Plant Atlas of the United States, 2014. Lombardy poplar. Populus nigra L. http://www.invasive.org/weedus/subject.html?sub=11530
IPC/FAO, 1999. International Poplar Commission. Databases. WorldWide Web page at http://www.agro.ucl.ac.be/efor/ipc.
Koskela J; Vries SMGde; Kajba D; Wühlisch Gvon, 2004. Populus nigra network. Report of the seventh (25-27 October 2001, Osijek, Croatia) and eighth (22-24 May 2003, Treppein, Germany) meetings [ed. by Koskela, J.\Vries, S. M. G.\de\Kajba, D.\Wühlisch, G. von]. Rome, Italy: International Plant Genetic Resources Institute (IPGRI), iv + 131 pp.
Kuzmenko IT, 1992. The soil and hydrological conditions of black poplar stands in the floodplain of the river Ural. Lesovedenie, 6:28-38.
Lapietra G; Coaloa D; Sampietro L, 1985. Timber tree rows in the Lombardy Plain. [I filari di piante da legno della pianura lombarda.] Quaderni di Ricerca, Centro di Sperimentazione Agricola e Forestale Istituto di Sperimentazione per la Pioppicoltura, Italy, No. 5, 18pp.; 29 ref.
Lieutaghi P, 1981. Il libro degli alberi ed arbusti. Le loro proprietà medicinali, il loro uso culinario, la bellezza dei loro fiori e delle loro foglie, l'importanza dei loro legni. Ed. Rizzoli Milano, Italy. II edition, 624-628.
Miller JH; Chambliss EB; Loewenstein NJ, 2010. A field guide for the identification of invasive plants in southern forests. General Technical Report - Southern Research Station, USDA Forest Service, No.SRS-119:126 pp.
O'Connell P; Stephens S, 2002. Pitcher's thistle monitoring report. Cadillac-Manistee District. Cadillac, MI, USA: Huron-Manistee National Forests, 14 pp.
Ostry ME; Wilson LF; McNabb HS; Moore LM, 1989. USDA Forest Service Agriculture Handbook, 677. Washington, DC, USA: US Department of Agriculture, 118 pp.
Peri P; Martinez Pastur G, 1998. Crecimiento en cortinas cortaviento de Populus nigra cv 'Italica' en Patagonia Sur (Argentina). Investigacion Agraria, Sistemas y Recursos Forestales, 7(1-2):73-83.
Pichot C; Cros ET du; Teissier du Cros E, 1988. Estimation of genetic parameters in the European black poplar (Populus nigra L.). Consequences on the breeding strategy. Annales des Sciences Forestieres, 45(3):223-237; 17 ref.
Popivshchii II; Prokazin AE; Routkovsky IV, 1997. Black poplar in Russian Federation. In: Populus nigra network. Report of the third meeting, 5-7 October 1996, Sárvár, Hungary. International Plant Genetic Resources Institute, Rome, Italy, 46-52.
Rathmacher G, 2009. Population genetic processes of a Populus hybrid complex: spatially explicit studies on gene flow of P. nigra and P. x canadensis as a basis for conservation measures. Saarbrücken, Germany: Südwestdeutscher Verlag für Hochschulschriften.
Salle G; Hariri EB; Andary C, 1991. Some mechanisms involved in resistance of poplar (Populus spp.) to mistletoe (Viscum album L.). Proceedings of the 5th international symposium of parasitic weeds, Nairobi, Kenya, 24-30 June 1991 [edited by Ransom, J.K.; Musselman, L.J.; Worsham, A.D.; Parker, C.] Nairobi, Kenya; CIMMYT (International Maize and Wheat Improvement Center), 270-278
Schalk PH, 1983. Twenty years testing of clones of European black poplar, Populus nigra L. [Twintig jaar toetsing van klonen van Europese zwarte populier, Populus nigra L.] Populier, 20(4):91-99; 6 pl.
Schirmer R, 1996. Improvements of the properties of poplar varieties by breeding. [Verbesserung der Sorteneigenschaften bei Pappel durch Zuchtung.] AFZ Der Wald, Allgemeine Forst Zeitschrift fur Waldwirtschaft und Umweltvorsorge, 51(12):678-679.
Sheikh MI, 1984. Conversion and use of poplar and willow biomass for food, fodder and energy in Asia. 17th Session of the IPC/FAO Ottawa, Canada, 1-4 October 1984.
Siebel HN; Blom CWPM, 1998. Effect of irregular flooding on the establishment of tree species. Acta Botanica Nederlandica, 47(2):231-240.
Society for the Diffusion of Useful Knowledge, 1829. The library of entertaining knowledge. Timber trees : fruits. London, UK: Charles Knight, 429 pp.
Tatsumi S, 1973. Studies on the management techniques of the street trees. I. The present situation of the street tree management in Japan. Kagawa Daigaku Nogakubu Gakuzyutu Hokoku Technical Bulletin, Faculty of Agriculture, Kagawa University, 25(1):61-69; EMB.
Thomas LK; Tölle L; Ziegenhagen B; Leyer I, 2012. Are vegetative reproduction capacities the cause of widespread invasion of Eurasian Salicaceae in Patagonian river landscapes? PLoS ONE, 7(12):e50652. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0050652
Tunctaner K, 1998. Conservation of genetic resources of black poplar (Populus nigra L.) in Turkey. Proceedings of international symposium on in situ conservation of plant genetic diversity, Antalya, Turkey, 4-8 November 1996, 265-270.
University of Georgia, 2009. University of Georgia - Center for Invasive Species and Ecosystem Health. Nonnative invasive species in southern forest and grassland ecosystems. http://www.invasive.org/south/
US Fish and Wildlife Service, 2006. Biological opinion for the Huron-Manistee National Forests land and resource management plan. East Lansing, MI, USA: US Fish and Wildlife Service, 257 pp.
US Fish and Wildlife Service, 2006. Pitcher's thistle (Cirsium pitcheri). 5-year review: summary and evaluation. East Lansing, MI, USA: US Fish and Wildlife Service, 29 pp. http://www.fws.gov/midwest/endangered/recovery/5yr_rev/pdf/pith5yrreview.pdf
USDA-NRCS, 2015. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/
Vackova K; Popiskova M; Benetka V, 1998. Rozliseni nekterych druhu rodu Populus L. na zaklade isoenzymove analyzy. Acta Pruhoniciana, 66:43-51.
Viart M, 1992. International register of the cultivars of Populus. Proc. of the 19th Sess. of the FAO/IPC 22-25 September 1992, Zaragoza, Spain, 1:57-105.
Vietto L; Giorcelli A, 1996. Il punto sulla defogliazione primaverile del pioppo. Sherwood-Foreste ed Alberi Oggi, 2(7):43-49.
ContributorsTop of page
24/06/15 Invasive Species Compendium sections added by:
Andrew Praciak, CABI, UK
Distribution MapsTop of page
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