All around the globe, humans have greatly altered the abiotic and biotic environment with ever-increasing speed. One defining feature of the Anthropocene epoch1,2 is the erosion of biogeographical barriers by human-mediated dispersal of species into new regions, where they can naturalize and cause ecological, economic and social damage3. So far, no comprehensive analysis of the global accumulation and exchange of alien plant species between continents has been performed, primarily because of a lack of data. Here we bridge this knowledge gap by using a unique global database on the occurrences of naturalized alien plant species in 481 mainland and 362 island regions. In total, 13,168 plant species, corresponding to 3.9% of the extant global vascular flora, or approximately the size of the native European flora, have become naturalized somewhere on the globe as a result of human activity. North America has accumulated the largest number of naturalized species, whereas the Pacific Islands show the fastest increase in species numbers with respect to their land area. Continents in the Northern Hemisphere have been the major donors of naturalized alien species to all other continents. Our results quantify for the first time the extent of plant naturalizations worldwide, and illustrate the urgent need for globally integrated efforts to control, manage and understand the spread of alien species.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1.

    , , & The Anthropocene: conceptual and historical perspectives. Phil. Trans. R. Soc. A 369, 842–867 (2011)

  2. 2.

    & Defining the Anthropocene. Nature 171, 171–180 (2015)

  3. 3.

    et al. Impacts of biological invasions: what’s what and the way forward. Trends Ecol. Evol. 28, 58–66 (2013)

  4. 4.

    et al. Naturalization and invasion of alien plants: concepts and definitions. Divers. Distrib. 6, 93–107 (2000)

  5. 5.

    et al. A proposed unified framework for biological invasions. Trends Ecol. Evol. 26, 333–339 (2011)

  6. 6.

    in Biological Invasions: a Global Perspective (eds et al.) 1–30 (John Wiley, 1989)

  7. 7.

    Global patterns of plant invasions and the concept of invasibility. Ecology 80, 1522–1536 (1999)

  8. 8.

    The Ecology of Invasions by Animals and Plants Ch. 4, 77–93 (Methuen, 1958)

  9. 9.

    , & The island biogeography of exotic bird species. Glob. Ecol. Biogeogr. 17, 246–251 (2008)

  10. 10.

    Of Asian forests and European fields: eastern U.S. plant invasions in a global floristic context. PLoS ONE 11, e3630 (2008)

  11. 11.

    & Trees and shrubs as invasive alien species – a global review. Divers. Distrib. 7, 788–809 (2011)

  12. 12.

    , , & 100 of the World’s Worst Invasive Alien Species (The Invasive Species Specialist Group (ISSG), 2000)

  13. 13.

    et al. Essential biodiversity variables. Science 339, 277–278 (2013)

  14. 14.

    World Geographical Scheme for Recording Plant Distributions Edition 2 (Hunt Institute for Botanical Documentation, 2001)

  15. 15.

    Six types of species-area curves. Glob. Ecol. Biogeogr. 12, 441–447 (2003)

  16. 16.

    & American Horticultural Society A–Z Encyclopedia of Garden Plants (DK Publishing, 2004)

  17. 17.

    , & The European Garden Flora (Cambridge Univ. Press, 2011)

  18. 18.

    , & Radiation of the Australian flora: what can comparisons of molecular phylogenies across multiple taxa tell us about the evolution of diversity in present-day communities? Phil. Trans. R. Soc. Lond. B 359, 1551–1571 (2004)

  19. 19.

    & European Code of Conduct for Botanic Gardens on Invasive Alien Species (Council of Europe, 2013)

  20. 20.

    Weeds in paradise: thoughts on the invasibility of tropical islands. Ann. Mo. Bot. Gard. 90, 119–127 (2003)

  21. 21.

    et al. A global assessment of endemism and species richness across island and mainland regions. Proc. Natl Acad. Sci. USA 106, 9322–9327 (2009)

  22. 22.

    in Biodiversity and Ecosystem Processes in Tropical Forests (eds , & ) 153–172 (Springer-Kluwer, 1996)

  23. 23.

    et al. The invasion paradox: reconciling pattern and process in species invasions. Ecology 88, 3–17 (2007)

  24. 24.

    , & China’s foreign trade: perspectives from the past 150 years. World Econ. 34, 853–892 (2011)

  25. 25.

    On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life (John Murray, 1859)

  26. 26.

    et al. Alien flora of Europe: species diversity, temporal trends, geographical patterns and research needs. Preslia 80, 101–149 (2008)

  27. 27.

    et al. Alien plants in checklists and floras: towards better communication between taxonomists and ecologists. Taxon 53, 131–143 (2004)

  28. 28.

    Review of ‘The Plant List, a working list of all plant species’. J. Veg. Sci. 23, 998–1002 (2012)

  29. 29.

    R Core Team. R: a language and environment for statistical computing v.3.1.2 (R Foundation for Statistical Computing, 2014)

  30. 30.

    & Taxonstand: taxonomic standardization of plant species names v.1.6 (R Foundation for Statistical Computing, 2014)

  31. 31.

    et al. Vegan: community ecology package v.2.0-10 (R Foundation for Statistical Computing, 2013)

  32. 32.

    , , & Achieving the convention on biological diversity’s goals for plant conservation. Science 341, 1100–1103 (2013)

  33. 33.

    et al. in Africa Environment Outlook 2 Ch. 7, 226–261 (African Ministerial Conference on the Environment and United Nations Environment Programme, 2006)

  34. 34.

    , et al. Flora Europaea (Cambridge Univ. Press, 1964–1980)

  35. 35.

    & Quantifying global international migration flows. Science 343, 1520–1522 (2014)

Download references


We thank the DAISIE team, the CONABIO team, E. Zykova, J. K. Vinogradova, S. R. Majorov, M. Schmidt, M. Newman, P. Thomas, R. Pooma, S. McCune, S. S. Tjitrosoedirdjo, H. Roy, S. Rorke, J. Danihelka, Z. Barina, A. Zeddam, S. Masciadri, Z. Barina and P. Nowak for data contributions, Z. Sixtová, B. Rüter, E. Mamonova, M. Krick, O. Michels and T. Scheu for digitizing data and internet searches, G. Müller and J. Moat for help with shapefiles, L. Cayuela for help with the R package Taxonstand, and T. Blackburn, A. Meyer and M. Rejmánek for comments on previous versions of the manuscript. M.v.K. and W.D. acknowledge funding by the Deutsche Forschungsgemeinschaft (KL 1866/9-1). F.E. acknowledges funding by the Austrian Climate and Energy Fund (project number KR11AC0K00355, SpecAdapt). J.P. and P.P. were supported by the Centre of Excellence PLADIAS (Czech Science Foundation project number 14-36079G) and long-term research development project RVO 67985939 (The Czech Academy of Sciences). P.P. acknowledges support by Praemium Academiae award from The Czech Academy of Sciences. M.W. and M.S. acknowledge funding from the Helmholtz Centre for Environmental Research (UFZ) and the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig (DFG FZT 118). P.W. and H.K. acknowledge funding from the Deutsche Forschungsgemeinschaft (DFG) Free Floater Program in the Excellence Initiative at the University of Göttingen and in the scope of the BEFmate project from the Ministry of Science and Culture of Lower Saxony. H.S. acknowledges support by the German VW-Foundation. F.J.C. and M.V. acknowledge support of the project Flora de Guinea Ecuatorial, 4 (CGL2012-32934). N.F. thanks the Projects ICM 05-002, PFB-23 and Fondecyt Postdoc 3120125. J.T. acknowledges the support of the Research Center of the College of Science, King Saud University, Riyadh, Saudi Arabia.

Author information


  1. Ecology, Department of Biology, University of Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany

    • Mark van Kleunen
    •  & Wayne Dawson
  2. Division of Conservation, Vegetation and Landscape Ecology, University of Vienna, 1030 Wien, Austria

    • Franz Essl
    • , Eduardo Chacón
    •  & Dietmar Moser
  3. Institute of Botany, Department of Invasion Ecology, The Czech Academy of Sciences, CZ-252 43 Průhonice, Czech Republic

    • Jan Pergl
    •  & Petr Pyšek
  4. German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, D-04103 Leipzig, Germany

    • Marten Winter
  5. Institute of Biochemistry and Biology, University of Potsdam, D-14469 Potsdam, Germany

    • Ewald Weber
  6. Biodiversity, Macroecology & Conservation Biogeography, University of Göttingen, Büsgenweg 1, D-37077 Göttingen, Germany

    • Holger Kreft
    •  & Patrick Weigelt
  7. Biota of North America Program (BONAP), Chapel Hill, North Carolina 27516, USA

    • John Kartesz
    •  & Misako Nishino
  8. Institute for Aquatic and Ecological Problems, Far East Branch, Russian Academy of Sciences, 680000 Khabarovsk, Russia

    • Liubov A. Antonova
  9. School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand

    • Julie F. Barcelona
    •  & Pieter B. Pelser
  10. Departamento de Biodiversidad y Conservación, Real Jardín Botánico, CSIC, Plaza de Murillo 2, 28014 Madrid, Spain

    • Francisco J. Cabezas
    •  & Mauricio Velayos
  11. Instituto Amazónico de Investigaciones Científicas Sinchi, Herbario Amazónico Colombiano, 110311 Bogotá, Colombia

    • Dairon Cárdenas
    •  & Nicolás Castaño
  12. Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, 111311 Bogotá, Colombia

    • Juliana Cárdenas-Toro
    •  & María P. Baptiste
  13. Arts Faculty, Monash University, 3145 Melbourne, Australia

    • Juliana Cárdenas-Toro
  14. Escuela de Biología, Universidad de Costa Rica, 11501 San José, Costa Rica

    • Eduardo Chacón
  15. Conservatoire et jardin botaniques de la Ville de Genève, 1292 Genève, Switzerland

    • Cyrille Chatelain
  16. Laboratory of Plant Taxonomy and Phylogeny, Tomsk State University, Lenin Prospect 36, 634050, Tomsk, Russia

    • Aleksandr L. Ebel
  17. Department of Botany, PO Box 77000, Nelson Mandela Metropolitan University, Port Elizabeth, 6031 South Africa

    • Estrela Figueiredo
  18. Centre for Functional Ecology, Departamento de Ciências da Vida, Universidade de Coimbra, 3001-455 Coimbra, Portugal

    • Estrela Figueiredo
  19. Facultad de Ciencias Forestales, Instituto de Ecología y Biodiversidad, Universidad de Concepción, Victoria 631, 403000, Concepción, Chile

    • Nicol Fuentes
  20. Botanic Garden Meise, Domein van Bouchout, B-1860, Meise, Belgium

    • Quentin J. Groom
  21. ARC-Plant Protection Research Institute, Pretoria 0001, South Africa

    • Lesley Henderson
  22. Department of Environmental Studies and Centre for Environmental Management Degraded of Ecosystems, University of Delhi, Delhi 110007, India

    • Inderjit
  23. Institute of Human Ecology SB RAS, Pr. Leningradasky 10, 650065 Kemerovo, Russia

    • Andrey Kupriyanov
  24. Programa de Pós-graduación en Ecología, UFRN, Campus Lagoa Nova, 59078-900 Natal, Brazil

    • Silvana Masciadri
  25. Oceanología y Ecología Marina, Facultad de Ciencias, Universidad de la República, Iguá, 4225, CP 11400, Montevideo, Uruguay

    • Silvana Masciadri
  26. Belize Tropical Forest Studies, PO Box 208, Belmopan, Belize

    • Jan Meerman
  27. Institute of Geography RAS, Staromonetny, 29, 119017 Moscow, Russia

    • Olga Morozova
  28. Department of Plant Biology, Southern Illinois University, Carbondale, Illinois 62901-6509 USA

    • Daniel L. Nickrent
  29. Oman Botanic Garden, Diwan of Royal Court, 122 Muscat, Oman

    • Annette Patzelt
  30. The Forest Herbarium (BKF), Department of National Parks, Wildlife and Plant Conservation, Chatuchak, Bangkok 10900, Thailand

    • Manop Poopath
  31. Department of Biology, Martin-Luther University Halle-Wittenberg, D-06108 Halle, Germany

    • Maria Schulze
  32. Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Carl-von-Ossietzky Straße 9–11, D-26111 Oldenburg, Germany

    • Hanno Seebens
  33. State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, College of Ecology and Evolution, Sun Yat-sen University, Guangzhou 510275, China

    • Wen-sheng Shu
  34. Department of Botany & Microbiology, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia

    • Jacob Thomas
  35. Naturalis Biodiversity Center (Botany section), Darwinweg 2, 2333 CR Leiden, the Netherlands

    • Jan J. Wieringa
  36. Biosystematics Group, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands

    • Jan J. Wieringa
  37. Department of Ecology, Faculty of Science, Charles University in Prague, CZ-128 44 Viničná 7, Prague 2, Czech Republic

    • Petr Pyšek
  38. Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland 7602, South Africa

    • Petr Pyšek


  1. Search for Mark van Kleunen in:

  2. Search for Wayne Dawson in:

  3. Search for Franz Essl in:

  4. Search for Jan Pergl in:

  5. Search for Marten Winter in:

  6. Search for Ewald Weber in:

  7. Search for Holger Kreft in:

  8. Search for Patrick Weigelt in:

  9. Search for John Kartesz in:

  10. Search for Misako Nishino in:

  11. Search for Liubov A. Antonova in:

  12. Search for Julie F. Barcelona in:

  13. Search for Francisco J. Cabezas in:

  14. Search for Dairon Cárdenas in:

  15. Search for Juliana Cárdenas-Toro in:

  16. Search for Nicolás Castaño in:

  17. Search for Eduardo Chacón in:

  18. Search for Cyrille Chatelain in:

  19. Search for Aleksandr L. Ebel in:

  20. Search for Estrela Figueiredo in:

  21. Search for Nicol Fuentes in:

  22. Search for Quentin J. Groom in:

  23. Search for Lesley Henderson in:

  24. Search for Inderjit in:

  25. Search for Andrey Kupriyanov in:

  26. Search for Silvana Masciadri in:

  27. Search for Jan Meerman in:

  28. Search for Olga Morozova in:

  29. Search for Dietmar Moser in:

  30. Search for Daniel L. Nickrent in:

  31. Search for Annette Patzelt in:

  32. Search for Pieter B. Pelser in:

  33. Search for María P. Baptiste in:

  34. Search for Manop Poopath in:

  35. Search for Maria Schulze in:

  36. Search for Hanno Seebens in:

  37. Search for Wen-sheng Shu in:

  38. Search for Jacob Thomas in:

  39. Search for Mauricio Velayos in:

  40. Search for Jan J. Wieringa in:

  41. Search for Petr Pyšek in:


M.v.K., P.P., W.D., F.E., J.P., E.W., M.W., H.K. and P.W. are the core GloNAF project members, who searched for and coordinated the collection of inventories of naturalized alien plants. M.v.K. and P.P. digitized the inventories and standardized the taxonomic names. J.K., N.M., L.A., J.B., F.C., D.C., J.C.-T., N.C., E.C., C.C., A.E., E.F., N.F., Q.G., L.H., I., A.K., S.M., J.M., O.M., D.M., D.N., A.P., P.P., M.P.B., M.P., M.S., H.S., W.S., J.T., M.V. and J.W. contributed naturalized plants inventories or other data. M.v.K. led the analyses and writing, with major inputs from P.P., W.D., F.E., J.P., M.W., H.K. and P.W., and further inputs from all other authors.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Mark van Kleunen.

Extended data

Supplementary information

PDF files

  1. 1.

    Supplementary Information

    This file contains Supplementary Text.

Excel files

  1. 1.

    Supplementary data

    This file contains Supplementary data.

About this article

Publication history






Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.