Get access

Alien flora of mountains: global comparisons for the development of local preventive measures against plant invasions

Authors

  • Keith L. McDougall,

    Corresponding author
    1. Department of Environment, Climate Change and Water, P.O. Box 733, Queanbeyan, NSW, Australia
      Correspondence: Keith L. McDougall, Department of Environment, Climate Change and Water, P.O. Box 733, Queanbeyan, NSW, Australia.
      E-mail: keith.mcdougall@environment.nsw.gov.au
    Search for more papers by this author
  • Jake M. Alexander,

    1. Institute of Integrative Biology – Plant Ecology, ETH Zurich, Universitätsstrasse 16, CH-8092 Zürich, Switzerland
    Search for more papers by this author
  • Sylvia Haider,

    1. Technische Universität München, Department of Ecology and Ecosystem Management, Emil-Ramann-Straße 6, D-85350 Freising, Germany
    Search for more papers by this author
  • Aníbal Pauchard,

    1. Facultad de Ciencias Forestales, Universidad de Concepción, Casilla 160-C, Concepción, Chile
    2. Institute of Ecology and Biodiversity (IEB), Santiago, Chile
    Search for more papers by this author
  • Neville G. Walsh,

    1. National Herbarium of Victoria, Locked Bag 2000, South Yarra, Victoria 3141, Australia
    Search for more papers by this author
  • Christoph Kueffer

    1. Institute of Integrative Biology – Plant Ecology, ETH Zurich, Universitätsstrasse 16, CH-8092 Zürich, Switzerland
    2. Department of Botany, University of Hawaii at Manoa, 3190 Maile Way, Honolulu, HI 96822, USA
    Search for more papers by this author

Correspondence: Keith L. McDougall, Department of Environment, Climate Change and Water, P.O. Box 733, Queanbeyan, NSW, Australia.
E-mail: keith.mcdougall@environment.nsw.gov.au

Abstract

Aim  We use data from 13 mountain regions and surrounding lowland areas to identify (1) the origins, traits and cultural uses of alien plant species that establish in mountains, (2) the alien species that are most likely to be a threat and (3) how managers might use this information to prevent further invasions.

Location  Australia, Canada, Chile, India, New Zealand, South Africa, Spain, Switzerland, USA.

Methods  Lists of alien species were compiled for mountains and their surrounding or nearby lowlands. Principal co-ordinates analysis was performed on a matrix of similarities created using presence/absence data for alien species. The significance of differences between means for (1) similarity metrics of lowland and mountain groups and (2) species traits of lowland and mountain alien floras was determined using t-tests. In seven of the 13 mountain regions, lists of alien species undergoing management were compiled. The significance of differences between proportions of traits for species requiring and not requiring management input was determined with chi-square tests.

Results  We found that the proximal lowland alien flora is the main determinant of a mountain region’s alien species composition. The highest similarities between mountain floras were in the Americas/Pacific Region. The majority of alien species commonly found in mountains have agricultural origins and are of little concern to land managers. Woody species and those used for ornamental purposes will often pose the greatest threat.

Main conclusions  Given the documented potential threat of alien species invading mountains, we advise natural resource managers to take preventive measures against the risk of alien plant invasion in mountains. A strategy for prevention should extend to the surrounding lowland areas and in particular regulate the introduction of species that are already of management concern in other mountains as well as climatically pre-adapted alien mountain plants. These may well become more problematic than the majority of alien plants currently in mountains.

Get access to the full text of this article

Ancillary