The measurements for the thesis were taken in August, September and October 2009 in the settlement of Podturn, in forest management unit of Poljane. The objective was to compare the productivity, costs and suitability of adapted farming tractor John Deere 6220 and of forwarder John Deere 1410 ECO III at wood extraction from regenerated stands in the Area of Rog. A time work study was also implemented. In the department 43, two stratums with similar surface were set up. In stratum B1 we used classical felling with chainsaw and wood extraction with tractor. In the stratum A2 we used a combination of machine and classic felling and exported the wood with forwarder. The Slovenian Forest Service marked the trees for the clearing before the beginning. The measurements of length and slope of trails were also implemented. During the classic felling, al the assortments were numbered and their volumes were measured; in the second stratum they were measured during the wood extraction. The results of the measurements have shown that the main influences on the efficiency and costs are the morphologic properties of the ground, concentration of wood throughout the length of the trail or on one spot (the place of loading), the length of extraction and the volume of individual assortment. The effects of tractor are 9,48 m3/operating hour or 7,26 m3/working hour, and of the forwarder are 25,6 m3/operating hour or 22,98m3/working hour. The costs of wood extraction with tractor are 5,75 /m3/operating hour or 5,63 /m3/working hour. For wood extraction with forwarder, the costs are 4,89 /m3/operating hour or 4,09 /m3/working hour. Use of tractor for extraction of fir-beech stands was estimated as suitable, as the tractor obtains good results despite the high levels of stoniness and rockiness. The selected type forwarder proved to be well adapted for extraction of heavy loads.
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