Ground-based logging systems are continually being used on steeper slopes. Australian researcher’s investigated one of these logging machines.
A Valmet 450 FXL self-levelling processor was studied in a 24 year old radiata pine plantation. The trees had never been thinned. The trees had been felled and stacked by a feller buncher. Slope conditions in the study area varied between 12 and 26 degrees. Previous research had shown productivity differences due to slope. The results of this research were interesting, as slope did not affect the productivity or cycle times. The reason for this was attributed to the processor working comfortably within its capabilities while processing relatively small trees (due the stand being unthinned). Also, the feller buncher placed trees into high density rows with their butts being well-indexed. This minimised processor boom and track movements and allowed the processor to pick up trees at the lower end of the steep slope class. Further research is necessary to determine how processor productivity would be affected when handling larger trees on steeper slopes. Source: http://www.crojfe.com/articles-822#825