Adaptive Silviculture for Climate Change: Early Structural and Compositional Outcomes in northern New England Northern Hardwood Forests

Abstract

Climate change introduces a suite of unknowns into conditions affecting forest growth, development, and health. Forest managers are in need of strategies for retaining forest integrity in the face of climate change that are regionally relevant and can be incorporated into current silvicultural planning processes. The Adaptive Silviculture for Climate Change project (ASCC) is an international network designed to examine adaptation strategies to address these changes through operational-scale treatments based on local expertise in forest management. ASCC involves four treatments: no action, resistance, resilience, and transition, representing a gradient of silvicultural approaches with increasing emphasis on adaptation to future climate conditions. We present five-year outcomes of these treatments at the northern hardwood ASCC site with emphasis on how structural complexity and compositional diversity change along the treatment gradient. We found that notable compositional changes were apparent primarily in the young regenerating class, while canopy composition remained similar across treatments. Structural diversity varied among treatments, with each treatment exhibiting unique spatial and canopy structural patterns with important linkages to future adaptation pathways. Our results suggest that management for increased adaptive capacity has immediate outcomes that can be described by  forest structure and more long-term outcomes that will be realized by changing composition of regeneration.