Productivity and cost of harvesting overgrowth brushwood from roadsides and field edges

摘要

Forest fuel production from overgrowth brushwood is an option when regular clearing of forest roadsides or edges of arable land has been neglected for some reason. The basic economic advantages of recovery are that the cost of harvesting can be offset by the existing clearing costs and income from the harvested biomass. The objectives of this study were to: 1) produce a productivity model for a machine unit that can continuously cut and accumulate brushwood trees during linear crane movement; 2) determine the kind of cases when brushwood biomass should be recovered, when the harvesting is based on a one- or two-machine configuration. The cost analyses were performed as a spreadsheet-based simulated treatment, using existing or the productivity models produced herein, and cost parameters for brushwood clearing and harvesting. The Risupeto feller-buncher unit studied in this study was capable of cutting and accumulating trees with a continuous movement that enabled the efficient harvesting of roadside and field-edge brushwood for fuel. The economic result in the brushwood harvesting with the harwarder and Risupeto forwarder configuration was strongly affected by the average volume of the brushwood trees, as well as harvesting removal on the site. Correspondingly, the roadside price of whole trees had a great impact on the potential revenue of brushwood harvesting.