Productivity and Cost of Clear-Cutting and Regeneration Operations with Small and Medium-Sized Forestry Machines in Utsunomiya City, Tochigi Prefecture, Japan

摘要

This study involved time studies of clear-cutting and regeneration operations, including site preparation and planting, in Utsunomiya City, Tochigi Prefecture, Japan. Then, this study analyzed productivity and cost between small and medium-sized machines of a small-scale logging contractor expanding their operations during merging small properties. The contractor used self-owned, small-sized machines (6-8 tons in weight) for bunching and processing operations in small areas (approximately 1 ha) between 2015 and 2016, and they used rented, medium-sized machines (9-13 tons) in larger areas (> 5 ha) between 2017 and 2018. The total cost of clear-cutting operations was highest in 2016 because manual processing was required for pine trees with crooked boles. In contrast, the total costs were comparable but lower in 2015, 2017, and 2018, although the machine sizes and operational conditions were different. Furthermore, the total costs were similar to that of other contractors conducting operations with relatively low costs in Japan. This implies that the contractor in this study conducted low-cost operations even with small-sized machines, or rented medium-sized machines with which the contractor was not used to operating. For regeneration operations, in 2017, the total cost of site preparations with medium-sized grapple loaders was lower than that with smaller ones. Therefore, they can easily expand their operations using rented medium-sized machines. Thus, renting medium-sized machines was a viable option for a small-scale logging contractor with lower costs in larger final felling operation areas.