The Ecology and Economics of Commercialization when Plants Carry a Risk of Becoming Invasive

Project Summary

The introduction of exotic plant species into the natural environment as an accidental by-product of commercial horticultural operations has been recognized for some time as a major problem in North America. The assessment of the threat of plant invasion must be concerned with analyzing the potential unintended risk of introduction associated with private nursery operations benefiting from sales of exotics. Prior efforts on the part of two of the principal investigators (Barbier and Knowler) to analyze policies to address the problem have been hampered by poor and incomplete data. The purpose of the proposed study is to enable the two PIs to rectify this shortcoming through collaborative interdisciplinary research with a third PI from ecology (Reichard). Useful sources of ecological and economic data in this collaborative research effort included

  • ecological data and analysis compiled by researchers on the project team and from elsewhere concerning the invasive characteristics of individual plants and the probability of invasion (e.g. Reichard and Hamilton, 1997);

  • ecological data on the introduction and spread of individual species that have become invasive (e.g. Thompson et al. (1987) for purple loosestrife (Lythrum salicaria).

  • economic data for the U.S. horticulture industry from the 1998 Census of Horticultural Specialties (USDA, 2000);  and

  • estimates of the economic damages imposed by individual plant species (e.g. Zavaleta (2000) for saltcedar (Tamarix spp) and Pimental et al. (2000), more generally).

Seed money grant from CIPM was sufficient to establish interdisciplinary research collaboration, identify data needs and conduct preliminary modeling. However, further funding will be needed to meet longer-term modeling and policy analysis objectives for identifying regulatory options for the management of potentially invasive plant species that are accidentally introduced through commercial horticultural operations.Co-investigators:Edward B. Barbier. Department of Economics and Finance, University of Wyoming, Laramie, Wyoming 82071-3985, USA Duncan J. Knowler. School of Resource and Environmental Management, Simon Fraser University, Burnaby B.C., Canada V5A 1S6.Sarah H. Reichard. Center for Urban Horticulture, University of Washington, Seattle, Washington 98195, USA Research Associate:  Joanne Burgess Funded by:  The Center for Invasive Plant Management, Montana State University