Harvesting the dead and decaying forests: Potential carbon storage in harvested wood products

Abstract

British Columbia (BC)'s forests and wood products industry face tremendous adversity in the face of the mountain pine beetle (MPB; Dendroctonus ponderosae) epidemic. The death and decay of one of BC's leading merchantable tree species (lodgepole pine; Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) threatens both the sustainability and climate mitigation opportunities in BC forests. Our study investigates the potential for carbon (C) storage in wood products in the post-epidemic phase of the MPB outbreak. In particular, we contrast the C-balance implications of converting MPB timber into long-lived wood products (i.e., lumber) (scenario 1) versus softwood pellets for bioenergy (scenario 2). Our findings highlight the importance of the C-cycle neutral assumption in determining the net C-balance of lumber versus pellets. Timber harvests for lumber resulted in a net C storage with this assumption (case 1), and net C emissions without this assumption (case 2). With uncertainty surrounding the future C-balance of BC forests, the current assumption of biomass-derived emissions being completely C-neutral may need to be re-evaluated.