By the Canadian Forestry Service, Pacific Forestry Centre
Research on impacts of forest harvesting on soils has shown that some operations are causing significantly reduced productivity for future crops. Additional stress on soils that may result from increasing wood recovery beyond the “close utilization” level is thus a matter for serious concern. The nature of operations directed toward increased wood recovery from cutovers is reviewed briefly. Literature dealing with physical soil impacts of forest harvesting and the subsequent effects on tree growth, particularly material published since 1970, is summarized, and the relevance of research results to increased biomass harvesting in British Columbia assessed. Additional wood recovery would involve mainly stemwood. Such recovery would be achieved primarily by conventional systems. Any increased physical soil impacts will likely result from an increase in traffic on existing roads and trails or a requirement for extra roads and trails to enable yarding of relatively small logs. As indicated by studies on stump extraction operations aimed at root-disease control, recovery of stumps and root systems would result in considerable additional soil disruption and a requirement for some nonconventional logging techniques.