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Developing Regional Invasive Species Watch Lists: Colorado as a Case Study

Published online by Cambridge University Press:  20 January 2017

Hilary R. Drucker*
Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO 80523
Cynthia S. Brown
Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO 80523
Thomas J. Stohlgren
U.S. Geological Survey, Fort Collins Science Center, 2150 Centre Ave. Bldg. C, Fort Collins, CO 80526-8118
Corresponding author's E-mail:


It is essential that we improve our ability to predict which nonnative species will become invasive in order to prevent their introduction and spread. Past attempts to foresee invasions have met with limited success, but increased computing power, increased availability of information about exotic species, and comprehensive evaluations of invasion potential are improving our ability to predict which species are likely to invade most successfully. We used data from Colorado and other states to develop an effective means of predicting the spread of invasive plant species among states. Qualitative criteria were used to develop a numerical threat index, which rates potential invaders based on distribution and abundance with respect to climate, biological characteristics, and preferred habitats of the species. Out of a compiled list of 388 species, we identified six invasive nonnative plants that are highly likely to invade Colorado, 10 with medium invasive potential and five with low potential. Species found to be likely to invade Colorado included garlic mustard, smooth distaff thistle, and Syrian beancaper.

Case Study
Copyright © Weed Science Society of America 

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Literature Cited

[APRS Implementation Team] Alien Plants Ranking System Implementation Team 2001. Alien Plants Ranking System Version 7.1. Flagstaff, AZ Southwest Exotic Plant Information Clearinghouse. Accessed: April 1, 2008.Google Scholar
Baker, H. G. 1965. Characteristics and modes of origins of weeds. Pages 146169. in. The Genetics of Colonizing Species. New York Academic.Google Scholar
Baker, H. G. 1974. The evolution of weeds. Annu. Rev. Ecol. Syst 5:124.Google Scholar
Campbell, F. and Kriesch, P. 2003. National Invasive Species Council. Invasive Species Advisory Committee. Pathways Task Team. Washington DC U.S. Department of Agriculture. 125.Google Scholar
Cronk, Q. C. B. and Fuller, J. L. 1995. Plant Invaders. 1st ed. London Chapman and Hall. 125.Google Scholar
Daehler, C. C. 1998. The taxonomic distribution of invasive angiosperm plants: ecological insights and comparison to agricultural weeds. Biol. Conserv 84:167180.CrossRefGoogle Scholar
Daehler, C. C. and Strong, D. R. 1993. Prediction and biological invasions. Trends Ecol. Evol 8:380.CrossRefGoogle ScholarPubMed
Goodwin, B. J., McAllister, A. J., and Fahrig, L. 1999. Predicting invasiveness of plant species based on biological information. Conserv. Biol 13:422426.Google Scholar
Hiebert, R. D. 1997. Prioritizing invasive plants and planning for management. Pages 195212. in Luken, J. O. and Thieret, J. W., editors. Assessment and Management of Plant Invasions. New York Springer.Google Scholar
Hobbs, R. J. and Humphries, S. E. 1995. Integrated management of plant invasion. Conserv. Biol 9:761770.Google Scholar
Hughes, G. and Madden, L. V. 2003. Evaluating predictive models with application in regulatory policy for invasive weeds. Agric. Sys 76:755774.Google Scholar
Kartesz, J. 1999. Biota of North America. Chapel Hill, NC North Carolina Botanical Gardens. Accessed: April 1, 2008.Google Scholar
Křivánek, M. and Pyšek, P. 2006. Predicting invasions by woody species in a temperate zone: a test of three risk assessment schemes in the Czech Republic (Central Europe). Divers. Distrib 12:319327.Google Scholar
Lake, J. C. and Leishman, M. R. 2003. Invasion success of exotic plants in natural ecosystems: the role of disturbance, plant attributes and freedom from herbivores. Biol. Conserv 117:215226.Google Scholar
Lee, M. 2001. Non-native plant invasions in Rocky Mountain National Park: linking species traits and habitat characteristics. Master's thesis. Fort Collins, CO: Colorado State University.Google Scholar
Mack, R. N. 1996. Predicting the identity and fate of plant invaders: emergent and emerging approaches. Biol. Conserv 78:107121.Google Scholar
Mack, R. N., Simberloff, D., Lonsdale, W. M., Evans, H., Clout, M., and Bazzaz, F. A. 2000. Biotic invasions: causes, epidemiology, global consequences, and control. Ecol. Appl 10:689710.Google Scholar
Maillet, J. and Lopez-Garcia, C. 2000. What criteria are relevant for predicting the invasive capacity of a new agricultural weed. The case of invasive American species in France. Weed Res 40:1126.Google Scholar
NatureServe 2007. NatureServe Explorer: An Online Encyclopedia of Life. Version 6.2. Arlington, VA NatureServe. Accessed: April 1, 2008.Google Scholar
[NIISS] National Institute of Invasive Species Science 2008. Online database. The United States Geological Survey, the Aeronautics and Space Administration, and the Natural Resource Laboratory. Accessed: April 1, 2008.Google Scholar
Pheloung, P. C., Williams, P. A., and Halloy, S. R. 1999. A weed risk assessment model for use as a biosecurity tool evaluating plant introductions. J. Environ. Manag 57:239251.Google Scholar
Pielke, R. A. Sr, Doesken, N., and Bliss, O. 2003. Climate of Colorado. Accessed: April 1, 2008.Google Scholar
Pimentel, D., Zuniga, R., and Morrison, D. 2005. Update on the environmental and economic costs associated with alien-invasive species in the United States. Ecol. Econ 52:273288.Google Scholar
Powell, M. R. 2004. Risk assessment for invasive plant species. Weed Technol 18:13051308.Google Scholar
Prinzing, A., Durka, W., Klotz, S., and Brandl, R. 2002. Which species become aliens. Evol. Ecol. Res 4:285405.Google Scholar
Pyšek, P. 2001. Past and future of predictions in plant invasions: a field test by time. Divers. Distrib 7:145151.Google Scholar
Pyšek, P. and Richardson, D. M. 2007. Traits associated with invasiveness in alien plants: where do we stand. Pages 97125. in Nentwig, W., editor. Biological Invasions. Ecological Studies, Vol. 193. Berlin Springer-Verlag.Google Scholar
Pyšek, P., Richardson, D. M., and Williamson, M. 2004. Predicting and explaining plant invasions through analysis of source area floras: some critical considerations. Divers. Distrib 10:179187.Google Scholar
R Development Core Team 2006. R: A Language and Environment for Statistical Computing. R Vienna, Austria Foundation for Statistical Computing. Accessed: April 1, 2008.Google Scholar
Reichard, H. S. and Hamilton, C. W. 1997. Predicting invasions of woody plants introduced into North America. Conserv. Biol 11:193303.Google Scholar
Rejmánek, M. 1999. Invasive plant species and invasible ecosystems. Pages 79102. in Sandlund, O. T., Schei, P. J., and Viken, A., editors. Invasive Species and Biodiversity Management. Dordrecht, Netherlands Kluwer Academic.Google Scholar
Rejmánek, M. 2000. Invasive plants: approaches and predictions. Aust. Ecol 25:497506.Google Scholar
Rejmánek, M. and Richardson, D. M. 1996. What attributes make some plant species more invasive. Ecology 77:1651.Google Scholar
Rice, P. 1997. INVADERS. Missoula, MT Division of Biological Sciences, University of Montana. Accessed: April 1, 2008.Google Scholar
Richardson, D. M., Allsopp, N., D'Antonio, C. M., Milton, S. J., and Rejmánek, M. 2000. Plant invasions—the role of mutualisms. Biol. Rev 75:6593.Google Scholar
Richardson, D. M., Holmes, P. M., Esler, K. J., Galatowitsch, S. M., Stromberg, J. C., Kirkman, S. P., Pyšek, P., and Hobbs, R. J. 2007. Riparian vegetation: degradation, alien plant invasions, and restoration prospects. Divers. Distrib 13:126139.CrossRefGoogle Scholar
Roy, J. 1990. In search of characteristics of plant invaders. Pages 335352. in di Castri, F., Hansen, A., and Debussche, M., editors. Biological Invasions in Europe and the Mediterranean Dordrecht. Netherlands Basin Kluwer Academic.CrossRefGoogle Scholar
Simberloff, D. 1996. Impacts of introduced species in the United States. Consequences 2:112.Google Scholar
Soulé, M. E. 1990. The onslaught of alien species, and other challenges in the coming decades. Biol. Invasions 4:233239.Google Scholar
Stohlgren, T. J. 2002. Beyond theories of plant invasions: lessons from natural landscapes. Comments Theor. Biol 7:355379.Google Scholar
Stohlgren, T. J., Crosier, C., Chong, G. W., Guenther, D., and Evangelista, P. 2005. Life-history habitat matching in invading non-native plant species. Plant Soil 277:718.Google Scholar
Stohlgren, T. J. and Schnase, J. L. 2006. Risk analysis for biological hazards: what we need to know about invasive species. Risk Analysis 26:111.Google Scholar
Sutherland, S. 2004. What makes a weed a weed: life history traits of native and exotic plants in the USA. Oecologia 141:2429.CrossRefGoogle Scholar
Templeton, A. R. and Levin, D. A. 1979. Evolutionary consequences of seed pools. Am. Nat 114:232249.CrossRefGoogle Scholar
[USDA, NRCS] U.S. Department of Agriculture, Natural Resources Conservation Service 2007. The PLANTS Database. Baton Rouge, LA National Plant Data Center. Accessed: April 1, 2008.Google Scholar
Westbrooks, R. G. 1991. Plant protection issues. A commentary on new weeds in the United States. Weed Technol 5:232237.Google Scholar
Westbrooks, R. G. and Eplee, R. E. 1996. Regulatory exclusion of harmful non-indigenous plants from the United States by USDA APHIS PPQ. Castanea 61:305312.Google Scholar
Wilcove, D. S., Rothstein, D., Dubow, J., Phillips, A. L., and Losos, E. 1998. Quantifying threats to imperiled species in the United States. Bioscience 48:607615.Google Scholar
Williamson, M. H. and Fitter, A. 1996. The characters of successful invaders. Biol. Conserv 78:163170.Google Scholar
Woodward, F. I. 1987. Climate and Plant Distribution. New York Cambridge University Press. 6375.Google Scholar