Operationalizing forest-assisted migration in the context of climate change adaptation: Examples from the eastern USA

There is increasing momentum to implement conservation and management approaches that adapt forests to climate change so as to sustain ecosystem functions. These range from actions designed to increase the resistance of current composition and structure to negative impacts to those designed to transition forests to substantially different characteristics. A component of many adaptation approaches will likely include assisted migration of future climate-adapted tree species or genotypes. While forest-assisted migration (FAM) has been discussed conceptually and examined experimentally for almost a decade, operationalizing FAM (i.e., routine use in forest conservation and management projects) lags behind the acceptance of the need for climate adaptation. As the vulnerability of forest ecosystems in climate change increases, FAM may need to become an integral management tool to reduce long-term risks to ecosystem function, despite real and perceived barriers for its implementation. Here we discuss the concept of operational-scale FAM and why it remains a controversial, not yet widely adopted component of climate adaptation. We present three case studies of operational-scale FAM to illustrate how the practice can be approached pragmatically within an adaptation framework despite the barriers to acceptance. Finally, we discuss a path toward advancing the wide use of operational-scale FAM.