In this thesis, we compare the process of wood preparation for the production of spruce shingles with the usual forest operation process. The field measurements took place in GGO Kranj, GGE Železniki, KO Dražgoše, on a forest parcel owned by a family farm. The research included a time study of felling and extraction for schingle production, a calculation of direct material costs for both operations, an analysis of skid trail damage caused by extraction and the calculation of standard times. In 3 hours and 2 minutes, three trees (8.401 m3) were felled, of which 4.82 m3 was suitable for shingle production. In felling, the most time was spent on the forest protective measures (25.1 %) and preparatory time (6.6 %), while in extraction, the most time was spent on wood piling (18.4 %) and preparatory work (20.3 %). Actual felling time was 19.30 min/m3, and extraction time was 10.18 min/m3. Material costs amounted to 6.08 EUR/oh (euros per operating hour) for felling and 13.34 EUR/oh for extraction. Due to extraction the rut depth exceeded 10 cm on 6.6 % of the skid length and exceeded 5 cm on 10.8 % of the length. The maximum rut depth measured was 17 cm, and the overall average rut depth was 3.9 cm. Felling time was 4.2 min/m3 shorter than prescribed standard times, while extraction time 9.27 min/t, which is 2 s/t lower than prescribed standard times (Uredba …, 2010; Uredba …, 2013). Material costs in felling were higher than in previous studies, mainly due to higher fuel prices, while in extraction material costs were lower for about 10 EUR/m3 because of lower purchase value of the tractor compared to other studies. The level of skid trail damage, according to the selected criteria, was acceptable. The process of preparing wood for shingle production differs significantly from conventional methods, particularly in work time structure and in the need for increased care to protect the stand and assortments from damage.
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