Results of harvesters and forwarders operations in Slovakian forests

Paper deals with performance, consumption of fuel and negative effects of harvester technologies on remaining stand at some workplaces in Central Slovakia.

Measurements were performed at OZ (affiliated state forest enterprise) Beňuš, Kriváň, Čierny Balog and ProPopulo Poprad Ltd. Harvester and forwarder Valmet 911.1/6 + Valmet 840.1/8, John Deere (JD) 1070 D + JD 810 D, JD 770 D + JD 810 D and JD 1270 D + 1110 D were used. The results show that during wheeled harvesters operation on the slopes with inclination to 40% it is possible to reach that number of mechanically damaged trees could be on average below 10%. Using statistical verification it was found that treatment intensity influences significantly damage to remaining stand.

Harvester JD 1070 D operating in tending felling reached an average performance only 2.3 m³.h^-1 with average volume of tree 0.14 m³ and slope inclination within 10%. We found that it is possible to reduce to a half the costs of the production of 1 m³ of wood by proper technological preparation of the workplace and modifying the technical parameters of machine according to the parameters of stand where harvesters would operate.