![]() Both operations resulted in a cost that was higher than the market values of biomass feedstock (less than $55/ oven dry ton (Odt)) in those regions at the time of operations. However, a commercial thinning operation in northern California recommended an integrated harvesting system be used, as the contract required removal of both sawlogs and biomass within one entry and a limited time. For example, a fuel reduction thinning contract in Arizona used a whole-tree chipping method, as the thinning treatment required removal of trees less than 12 cm DBH. Decisions to select one of the three biomass removal systems described are made based on the amount (e.g., tons/ha) and spatial location/distribution of biomass, material types (slash or whole trees), economics, and work requirements. Integrated harvesting operations utilize forest machinery to harvest sawlog and biomass at the same time (i.e., with one-entry thinning).ĭepending on which biomass removal system is selected, operational logistics and machinery used are often different and highly variable, which directly effects the cost of biomass removal. Slash recovery operations take place after harvesting sawlog materials, however, no sawlogs are harvested in whole-tree chipping operations. Slash recovery operations focus on residues left at landings or along the roadside from timber sales, including commercial thinning, while whole-tree chipping systems are often used when small-diameter (less than 20 cm DBH) trees produced from fuel reduction thinning need to be removed. ![]() ![]() Three types of biomass harvesting operations are commonly used to remove biomass: slash recovery, whole-tree chipping, and integrated harvesting. This also has the potential added benefit of producing energy from a renewable source. Mechanical removal of biomass from federal forestlands is often preferred, as this allows biomass to be removed without generating smoke and the risk of fire escape associated with prescribed burning or pile burn. Their simulation allowed for three alternative prescriptions: (a) larger diameter tree removals favored, based on stand density index, (b) smaller diameter tree removals favored, also based on stand density index, and (c) thin-from-below prescription designed to achieve fuel hazard reductions. They found that when product sales (including some larger trees greater than 21 inches diameter breast height (DBH)) were incorporated into prescriptions, more than 25% of treated areas would have net economic benefits. used Monte Carlo simulation to assess economic benefits from mechanical treatments on western forestlands. Other methods can also be used to improve the economic potential of fuel treatments. In Montana, it has been estimated that hazard reduction thinnings could yield upwards of four times more biomass than standard precommercial thinnings. However, for both types of treatments, a common denominator is the challenge of finding long-term economically viable markets. It is also important to distinguish between thinnings as part of normal silvicultural treatments and hazard fuel thinnings which are designed to reduce fire risk, protect property, and increase the safety of community residents. All of these trends-including significant unknowns, like the volatile prices of fossil energy-are likely to affect the economics of biomass removal and use in western forests. Social needs of residents in wildland urban interfaces will play an important role, especially in an era of megafires. New markets and technologies, such as biofuels, for use in the aviation industry, torrefied wood, mobile pyrolysis, and wood coal cofiring could greatly change the landscape of biomass use. State policies are likely to help guide the growth of biomass utilization for energy products. Long-term stewardship projects could play a role in influencing project economics while being conducive to private investment. Our research-which focused on the socioeconomic factors associated with biomass removal, production, and use-identified several important trends. Western states vary greatly in the extent and utilization of forest resources, the proportion of land under federal ownership, and community and stakeholder structure and dynamics. We examine several issues of importance, including biomass supply chains and harvesting costs, innovative new uses for bioenergy products, and the policy framework in place to provide incentives for biomass use. Many socioeconomic constraints exist for biomass removals from federal lands in the western U.S.
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