Silviculture for Climate Resilience

This abstract explores the Adaptive Silviculture for Climate Change (ASCC) study and the underlying "RRT" framework (Resistance, Resilience, Transition) as crucial strategies for managing forests in the face of accelerating climate change. Developed by US Forest Service conservation geneticist Constance Millar and her colleagues in 2007, this framework provides foresters with flexible, adaptive options to address an uncertain future. The RRT framework outlines three primary options: • Resistance: This strategy focuses on conserving and protecting existing natural communities, often through light treatments like removing invasives or thinning to enhance dominant species. It is considered a "holdout" strategy, acknowledging its potential futility in the long run. • Resilience: Embracing Aldo Leopold's concept of "intelligent tinkering," this involves diversifying degraded or simplified forests through silvicultural treatments during harvests, effectively "tinkering" with species composition to favor better-adapted species. • Transition: This represents a more drastic measure, aiming to change ill-adapted forests into novel ecosystems, such as replacing struggling red pine plantations with thriving Norway spruce. The fundamental premise of RRT is that the future forest's species composition will determine its fate. All RRT legs involve active silviculture, rejecting the notion that "forests will be just fine on their own". The ASCC study, a nationwide effort, tests these strategies across 15 sites, including one in New Hampshire where different RRT treatments are applied, incorporating enrichment planting for species like red spruce, white pine, and even non-native species for assisted migration. Despite these efforts, progress is often slow due to the small fraction of forest area regenerated annually, highlighting the challenge and urgency of active forest management.