Life-Cycle Impacts of Forest Resource Activities in the Pacific Northwest and Southeast United States

Abstract

Environmental impacts associated with the life-cycle of forest resource activities were assessed for the Southeastern U.S. and Pacific Northwest supply regions as a component of a broad analysis of life-cycle inventory data on wood products produced in these regions.The assessment included all of the inputs to establish a forest stand (seedlings, site preparation, and planting), to treat that stand through harvest maturity (thinning and fertilization) and to harvest the merchantable logs from the stand.To provide a region-wide representation under different management strategies, three forest management scenarios were structured for both the Southeastern U.S. and Pacific Northwest regions.Within each region, three combinations of management intensity and site productivity were allocated to acreages corresponding to the U.S. Forest Service RPA allocation and then merged into a single estimate of yield and the corresponding harvesting impacts.This allocation of acreage to management intensity/site productivity class provided a representative base case for each region.A more intensive management alternative was created for each region by reallocating acres to higher management intensity classes.Harvesting activities were segmented into five stages to allow development of all inputs and outputs: (1) felling, (2) processing (bucking, limbing, cutting to length), (3) secondary transportation (skidding and yarding), (4) loading, and (5) hauling to a process point.The costs and consumption rates of energy and materials for these activities drove the log outputs, emissions, and carbon pools.Logs are allocated to wood product facilities, the primary product of the analysis, or pulp and paper mills as a co-product from the forest.Non-merchantable slash is generally left on site and is disposed of Wood and Fiber Science, 37 Corrim Special Issue, 2005, pp.30 -46