Forest Operations Using a Combi–Forwarder in Deciduous Forests

Abstract In the last decade, technological innovation in the forest operations sector has allowed levels of mechanization alternative to agricultural tractors and animal logging. These machines are used to load logs from skid roads and move logs to the next pile, until the load space is fully loaded. Fortunately, in recent years the development of new technological progresses in forestry mechanization created an alternative operation on ground-based system with the use of a combi-forwarder for wood forwarding. These innovative machines have the advantage that only one machine can perform logs bunching and primary transport. Infact, pull stems by the winch from the stump to the road, after they have been cross-cutted by chainsaws, it loads by the forwarder’s crane the logs and transports them to the landing, where they are unloaded with the crane in piles. The aim of the present study was to analyse the operational time consumption, to estimate the productivity of the combi–forwarder with a built-in single-drum winch in beech stands evaluating the forwarding and winching distances, log’s volume transported per turn by the machine, as well as the extracting costs. The study was conducted in low-intensity shelterwood cuttings in beech forest, located in Western Balkan Mountains, Bulgaria. The mean productivity of the combi–forwarder was 7.09 m 3 PMH − 1 and 6.11 m 3 SMH − 1 close to that of the cable skidders and forwarders in similar conditions. The net costs for the studied combi–forwarder were calculated of 25.33 € per productive machine hour and 4.13 € per m 3 . The variable costs (70%) have a leading role, followed by labour costs (22%) and fixed costs (8%). The use of a combi-forwarders facilitates chainsaw operators, as some of the operations are carried out at the roadside in better working conditions: flat terrain and support of the crosscutting phase. The results from the study are useful to introduce and to integrate the combi–forwarders with shelterwood systems and to achieve economic and environmental efficiency of timber harvesting in deciduous forests.