Acta Scientiarum Polonorum
Silvarum Colendarum Ratio et Industria Lignaria

Cut-to-length technology for broadleaved species is a novelty in forest operations, also causing various difficulties. The purpose of the study was to find effects of an application of the CTL 40HW head[1] for broadleaves mounted on the UTC 150-6LS harvester used in a thinning operation in a birch stand in northern Poland. For this, productivity, the level of damage in the remaining stand and soil disturbances were analysed. The results present a satisfactory outcome: the average productivity was 13.4 m3·h-1 (h of operational time). Analysis of the remaining stand showed 4-7% trees with damage. Analysis of the soil on the harvester strip roads showed a bulk density increase of 0.16-0.21 g·cm-3. It was also observed that there was lower mean soil moisture after harvesting, though this change was not statistically confirmed. The biggest soil penetration resistance increase was observed after two machine drives: 50% on 30 cm of depth and after a single drive 45% on 10 cm of depth.