Chapter 3: Old growth, disturbance, forest succession, and management in the area of the Northwest Forest Plan

In this chapter, we examine the scientific basis of the assumptions, management strategies, and goals of the Northwest Forest Plan (NWFP, or Plan) relative to the ecology of old-growth forests, forest successional dynamics, and disturbance processes. Our emphasis is on “coarse-filter” approaches to conservation (i.e., those that are concerned with entire ecosystems, their species and habitats, and the processes that support them) (Hunter 1990, Noss 1990). The recently published 2012 planning rule has increased emphasis on land management rooted in ecological integrity and ecosystem processes, using coarse-filter approaches to conserve biological diversity (Schultz et al. 2013). Fine-filter approaches (e.g., species centric), which are also included in the 2012 planning rule, are discussed in other chapters. We synthesize new findings, characterize scientific disagreements, identify emerging issues (e.g., early-successional habitat and fire suppression effects) and discuss uncertainties and research needs. We also discuss the relevance of our findings for management. Climate change effects on vegetation and disturbance and possible responses (adaptation and mitigation) are addressed mainly in chapter 2 of this report. Although, our effort is primarily based on published literature, we bring in other sources where peer-reviewed literature is lacking, and we conduct some limited analyses using existing data. We are guided by the NWFP monitoring questions, those from federal managers and our reading of the past three decades of science.