The Climate-Matching Approach to Weed Risk Assessment

As invasive plants continue to increase worldwide, there is an increased demand to assess and categorize species for management priority. This study assessed the use of a climate-matching model to improve predictions of plant species spread. We analyzed species that had been chosen using expert opinion for designated listing as able to spread widely in California from a small distribution in 1999, and determined whether this model could have predicted more accurately the subsequent spread of these species.  The model generally performed better than the expert opinion ranking. Although the model predictions showed varied success with trees and riparian species, good predictive outcomes were obtained for all herbaceous species. Climactic preferences and limitations should be considered for prioritization of invasive species when planning large-scale management and early detection programs.