Time Consumption and Costs of Mechanized Felling and Processing of Deciduous Trees With The Waratah H 415 Harvester Head With Top-Saw

For large parts of Europe and in particular for Germany, the proportion of deciduous tree species, including the standing volume, stand age and diameter of trees, is significantly increasing (compare third National Forest Inventory). Harvesting deciduous trees with modern harvester is extremely challenging and less intensively studied in terms of time consumption, costs and yield. It has furthermore a strong impact on occupational safety due to hazards such as falling dead branches. The present work was carried out in October 2023 in Homberg/Effze, Germany. A regeneration thinning was done in a 95-year-old mixed forest stand, dominated by deciduous trees, in specific European beech (Fagus sylvatica), European ash (Fraxinus excelsior), sessile oak (Quercus petraea) and sycamore maple (Acer pseudoplatanus). We performed a time work study to investigated the time consumption and costs of tree felling and processing with a harvester HSM 405 H2 8 WD equipped with a harvester head Waratah R415/1000 with top-saw. In total 115 runs were analyzed and 591 logs were count. Using the top-saw resulted in a higher yield of 0.63 m3solid or 33% per harvested deciduous tree. The time consumption was slightly lower (-5%) using the top-saw compared to not using it and instead changing the grip of the harvester head. Both, higher yield and lower time consumption, resulted in 18.7% lower harvesting costs when using the top-saw compared to the costs without using the top-saw.