After restoration of open forests, do changes in ecological processes follow?

Open oak and pine forests, which typically have a treed overstory and grassland understory, were historically prevalent across many regions of the United States. These forests have declined due to changes in land use and disturbance regimes, with numerous consequences for forest structure, plant and wildlife diversity, and function. Management typically presumes that changes in ecological processes will follow restoration. However, a review of the evidence for this assumption - and the processes underlying the successful restoration of open forest structure and herbaceous plant composition - is long overdue, particularly given the effort and resources many agencies are investing in large-scale restoration programs. Such programs include the Collaborative Forest Landscape Restoration Programs (CFLRP) projects; a “Million Acre Challenge” to add substantially to the amount of longleaf pine forests and shortleaf pine ecosystems across much of the southeastern United States; and the Healthy Forest Initiative and Shared Stewardship effort to restore historically open forests on landscape scales.

Ecological processes might not respond to management actions and restoration may not result in expected outcomes for a number of reasons, including fire regime departure, land use, and invasive species. Topics for this review include shifts in the ratios of overstory/understory production and aboveground/belowground production; variable benefits for different plants; genetic integrity and diversity of restored plants; water and nutrient cycling; light and environmental conditions; disturbance (fire severity and spread, fuels); efficacy of specific treatments (controlled burns, thinning, mechanical control, etc.); spatial patterns of regeneration; availability of planting stock; wildlife response; and explicit consideration of the observed variance in response to the same treatment across sites and ecosystems. It also is important to consider the importance and success of restoration in the face of climate change and climate-mediated changes to disturbance.

Approach

A synthesis of literature to be submitted as a Tamm Review for Forest Ecology and Management.