Woody biomass is a renewable carbon resource option for bioeconomy development and energy expansion. Understanding the spatial and temporal accessibility, quantity, and associated costs of woody biomass is critical for informed policy making and strategic planning. The Forest Sustainable and Economic Analysis Model (ForSEAM) is a dynamic linear optimization model developed to identify sources of conventional timber products and woody biomass feedstock from the United States (US) timberland. The model integrates demand, economic feasibility, and environmental sustainability with respect to current and future sources, land ownership, tree ages and species, harvesting systems, and costs for 305 regions in the conterminous US. Each region consists of a set of timber resources that can potentially be harvested for conventional industrial use and woody biomass for alternative use, such as bioenergy. Woody biomass sources include logging residues and the removal of small-diameter whole trees. Sustainability constraints ensure that harvests do not exceed annual growth, maintain proximity to roads, and account for changes in forest attributes over time. Three hypothetical pathways for woody biomass supply from 2021 to 2050 were simulated, and optimal solutions were presented. Results indicate that the United States can supply approximately 40 million dry tons forest woody biomass annually under a conservative supply pathway, 50 million dry tons under a moderate pathway, and up to 75 million dry tons under a high supply pathway. The estimated shadow value for additional woody biomass reaches approximately $95 per dry ton by 2050 under the high supply pathway, indicating increasing reliance on higher cost whole tree harvesting. The model framework can be used for policy analysis related to bioeconomy development and may be adapted for other regional uses.
