Confronting challenges to economic analysis of biological invasions in forests†

Biological invasions of forests by non-indigenous organisms present a complex, persistent, and largely irreversible threat to forest ecosystems around the globe. Rigorous assessments of the economic impacts of introduced species, at a national scale, are needed to provide credible information to policy makers. It is proposed here that microeconomic models of damage due to specific invading organisms be aggregated across the forest landscape by considering the rate at which acute, short-run economic impacts accumulate over time and space. By estimating the economic costs and damages associated with the most consequential pests within each pest guild and each sector of the forest economy, a better indication of the economic consequences of biological invasions can be obtained and used to inform policy analysis.