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Forest residues generated from timber harvesting operations, in the form of dead trees, branches, tree tops, chunks (offcuts), non-merchantable tree species and small-diameter trees, have traditionally been regarded as economically low value products. These by-products are generally utilized as feedstock for energy production, as they are widespread, renewable, and can be used to offset the use of fossil fuels and reduce greenhouse gas emissions [1].In regions where there are markets for biomass or pulp, a variety of treatments, including debarking stems, removing foliage, field drying, etc. are carried out [2,3]. Such treatments have been found to accelerate drying, reduce contamination, and eventually enhance the quality of the feedstock [4]. The cost associated with these treatments, while documented, often cannot be compared , because the harvest operations are species, site, and practice specific [5]. However, documenting these operations can help in formulating specific strategies that can be adopted in regions with limited bioenergy markets.In northern California, approximately 157 and 110 oven dry metric tons (ODMT) ha -1 of forest residues can be recovered from a typical even-age managed ground-based and cable yarding operations, respectively [6]. However, the markets (primarily restricted to wood based power plants) for these woody biomass are limited by the transportation distance due to the low price [7]. This means, forest residues generated from most of the timber harvest units out of the power plant procurement regions are piled and burned on-site. These slash burning are additionally restricted to specific burn windows of the year [8]; and can have a negative impact on air quality and human health [9].One of the greatest barriers for utilizing traditional feedstock is due to the low price paid by the prevailing markets such as power plants. This price (approximately 50 $ BDT -1 ) in large prohibits from implementing any commercial biomass removal projects [10,11]. Emerging biomass conversion technologies (BCT) such as torrefaction, briquette, and gasification can increase the economic potential of

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In this study, we evaluated the productivity and cost of each component in a unique centralized biomass recovery operation to determine cost-effective system logistics. The system was divided into three segments: collection, comminution, and transportation. Cost analysis determined a stump-to-truck and transportation cost of $30.39 and $13.91 per bone dry ton (BDT), respectively. These costs did not include support equipment, overhead, profit, or risk allowance. Transportation cost was evaluated for a total one-way haul distance of 15 miles. To control overall cost it is imperative to maintain maximum productivity of processing, our most expensive component. Therefore, upstream and downstream practices were examined to determine how they influenced the system. Analysis of the loader operation showed a 33 percent increase in cycle time when handling hardwood whole trees piled at a landing, compared with conifer slash piled within the unit. Regression analysis of the modified dump truck used in the prehaul confirmed that distance had a significant impact on overall centralized biomass grinding operations. Sensitivity analysis showed that a 20 percent reduction in productivity owing to increased travel time resulted in a 25 percent increase in grinding cost. A decoupled transport system used all-wheel drive tractors to haul comminuted biomass from the grinder to a trailer landing, where regular highway tractors completed the trip to the power plant. This system reduced delays in loading and improved access to the grinding location. Through an understanding of the complete system, a manager could identify cost saving elements, adjust upstream productivity to meet demand, and reduce the overall cost of a centralized biomass recovery operation.