Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Kelly M. Andersen; Bridgett J. Naylor; Bryan A. Endress; Catherine G. Parks
    Date: 2015
    Source: Applied Vegetation Science. 18: 683–693.
    Publication Series: Scientific Journal (JRNL)
    Station: Pacific Northwest Research Station
    PDF: Download Publication  (322.72 KB)


    Questions: Mountain systems have high abiotic heterogeneity over local spatial scales, offering natural experiments for examining plant species invasions. We ask whether functional groupings explain non-native species spread into native vegetation and up elevation gradients.We examine whether non-native species distribution patterns are related to environmental variables after controlling for elevation and, thus, driven by niche processes.

    Location: TheWallowa Mountains, northeast Oregon, USA.

    Methods: We surveyed non-native plant species along three mountain roads and into the native habitat matrix to assess the extent of invasion success along distance from roadside and elevation gradients. We used GLM to predict single species occurrence probabilities, LMM to examine differences in distribution patterns among functional types, and pCCA to examine multivariate responses of the non-native community to ecological variables.

    Results: Probability of occurrence of the eight focal invasive species was not significantly related to distance from the road, but declined with elevation. Nonnative species with annual life history strategies were more restricted to lower elevations than perennial species. Non-native species considered invasive occurred at lower minimum elevations than naturalized species. Shifts in the species composition of the non-native plant community were related to changes in soil and climate variables.

    Conclusions: Our results suggest that invasive species have similar patterns of habitat associations and spread from roadsides to interior vegetation zones, whereas naturalized species partition environmental gradients in this semi-arid montane ecosystem. Furthermore, annual and invasive species groups occupy lower elevations and perennial and naturalized species groups have invaded further up the mountain roads and into the native vegetation. Thus, functional groupings may explain contrasting distribution patterns of non-native species and could be used to inform management strategies for non-native species.

    Publication Notes

    • Visit PNW's Publication Request Page to request a hard copy of this publication.
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.


    Andersen, Kelly M.; Naylor, Bridgett J.; Endress, Bryan A.; Parks, Catherine G. 2015. Contrasting distribution patterns of invasive and naturalized non-native species along environmental gradients in a semi-arid montane ecosystem. Applied Vegetation Science. 18: 683-693.


    Community assembly, Disturbance, Elevation gradient, Functional groups, Habitat filtering, Non-native species, Plant invasions, Species turnover

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page