%0 Articles %T Methodology for choice of harvesting system for energy wood from early thinning %A Laitila, Juha %D 2012 %J Dissertationes Forestales %V 2012 %N 143 %R doi:10.14214/df.143 %U http://dissertationesforestales.fi/article/1929 %X The primary aim of the present study was to develop a methodology for estimating the procurement cost of forest chips from early thinnings. The most common logging systems and supply chains of forest chips used in early thinnings in Finland were compared at stand and regional level using productivity models and cost parameters obtained mainly from the sub-studies of this thesis. Available volumes of whole trees and delimbed stems from early thinnings around the city of Jyväskylä was based on sample plot data from the Finnish National Forest Inventory. Furthermore, a decision tree was constructed for selecting an harvesting method for energy wood originating from early thinnings. Forwarding productivity following mechanised cutting was significantly higher compared to productivity after motor-manual cutting. Mechanised cutting by the harvester enables felling and bunching of whole trees into large grapple loads close to strip roads, which facilitates increasing forwarding output and cost reducing costs. The two-machine system comprised of a harvester and a forwarder was the most cost-efficient logging system due to higher efficiency in cutting and especially in the forwarding phase. The cost of motor-manual whole-tree cutting was equal to mechanised whole-tree cutting, while forwarding cost after motor-manual cutting was almost double that after mechanised cutting. Using a forwarder-based harwarder resulted in the highest logging costs. However, with large tree volumes and removals its costs were almost equal to those of motor-manual-based logging. In order to achieve a breakthrough for the harwarder system, costs must be reduced by improving both machine technology and working techniques. Available volumes and procurement costs of fuel chips made of small-diameter trees were compared at regional level. The trees were harvested either by the multi-stem delimbed shortwood or whole-tree method and chipped by a truck-mounted drum chipper at the roadside.Based on the availability analysis, delimbing reduced regional cutting recovery by 42% compared to whole tree harvesting, when the minimum concentration of energy wood was set at 25 m³ ha-1. Delimbing reduced the recovery rate of biomass thereby also reducing the number of potential harvesting sites with adequate removal rates. However, the study showed that forest energy potential can be increased and procurement costs reduced by applying the shortwood method with multi-stem delimbing in stands stands where whole tree harvesting is not recommended because of potential nutrient losses or other ecological reasons. Using versatile machinery in thinnings increases the flexibility of forest operations and thereby improves cost-efficiency.