Utilization of Low-value Lumber from Small-diameter Logs Harvested in Pacific Northwest Forest Restoration Programs in Hybrid Cross Laminated Timber (CLT) Core Layers: A Market Response

Graduation date: 2017The United States spends about $2 billion each year fighting wildfires. While it is a costly operation, mechanized thinning of dense federal forests is one preventative strategy that generates high volumes of small logs. These small logs are often used for wood chips, pulp, or biomass because of the high hauling costs to deliver small logs to sawmills capable of processing them into lumber. Exploration into current markets for small-diameter logs (4 to 6 inches) harvested off federal timberlands instigated research questions to assess whether cross- laminated timber (CLT) panels could offer another outlet for low grade lumber processed from small logs.\ud \ud This thesis is part of a larger project where lumber from small logs harvested in restoration programs was examined for use in CLT; panels were manufactured utilizing lumber from small logs and the mechanical properties were assessed. While another team focused on mechanical testing to examine the technical viability of this concept according to current manufacturing standards, the objective of this thesis was to assess the practical feasibility of this conception within the supply chain (C. Lawrence, 2017). This research focuses on the Blue Mountains–a region in eastern Oregon. The approach was based on analysis of previous literature, Forest Service Cut & Sold reports, and semi-structured in-person and telephone interviews of federal timberland foresters, sawmill personnel, and management of current and potential cross-laminated timber manufacturers.\ud \ud The principal findings of this project were that approximately 147 million board feet is allowed for sale each year from the three federal forests in the Blue Mountains, which include the Malheur, Umatilla, and Wallowa-Whitman. About 21% of the current volume–30.6 million board feet–is estimated to be small logs. Four sawmills are within sourcing radius of the three national forests in the Blue Mountains and have a current capacity to process 172.5 million board feet. Current annual CLT manufacturing capacity within Oregon & SW Washington is 274,000 ft3, and if two potential entrants begin production of CLT, this capacity is likely to increase to almost 1.5 million ft3 per shift on an annual basis.\ud \ud In order for all the small diameter sawlogs harvested in these three federal forests to be used in the center layers of CLT panels, approximately 0.16% to 0.42% of the demand for CLT construction would have to exist, as defined by FPInnovations’ framework that estimated the opportunity for increased softwood lumber consumption driven by CLT projects. Current and potential manufacturers of CLT would need to operate two shifts, and approximately 38% of the\ud small log processing capacity in the region would be utilized. This would represent a greater volume and proportion of federal timber being processed at these facilities. Additional scenarios are explored within this thesis that allow the various entities within the supply chain to define the driving or limiting factors in this concept; broad effects throughout the supply chain are briefly reported.\ud \ud At the time of research, Douglas fir 2x8 No. 3 grade lumber was the preferred lumber product specified by current CLT manufacturing within the region for use in center layers of panels. Of six scenarios using different species and dimensions, only one scenario–SPF-S 2x6 No. 3–was marginally competitive, as it was estimated to save $0.03/ft3 on raw material costs.\ud \ud However, it seems that marginal savings on raw material costs are inadequate to persuade CLT manufactures with limited automation to specify smaller lumber dimensions due to increased material handling and possibility of additional warp or twist caused by small logs. If more automation was present in cross-laminated timber manufacturers, this conclusion may differ. This research suggests that if the regional supply chain in the Blue Mountains were to process more small diameter logs into lumber, this will increase the available supply of 2x4 and 2x6 dimensions of lumber for use in a variety of different markets rather than for exclusive use in the center layers of cross-laminated timber panels