Three geometrical thinning methods were tested and compared with conventional selective thinning. The geometrical harvesting methods were two boom corridor (BCT1, BCT2) and one machine corridor (MCT) methods. In BCT-methods all trees were removed from 1,5m wide and 10m deep corridors which were placed on both sides of the trip road at each operational stop. In BCT1 three corridors were made on both sides of the machine at various angles to travel direction at each operational stop at 10m intervals. In BCT2 corridors were made only at 60 degree angle and 3m intervals. In MCT trees were removed only from the front of the machine. BCT2 had the highest productivity in harvesting, forwarding and overall productivity (3.96 m3/E0). The selective thinning was even in harvesting but lower in forwarding and overall productivities (3.82 m3/E0). BCT1 productivity was lower in harvesting and forwarding with 3.68m3/E0 overall productivity. In MC the dense treetops in front of the machine often inhibited the felling and forced the harvester to reverse which reduced the overall productivity to 3.57 m3/E0.

Keywords: geometrical thinning, energy wood, productivity, Scots pine