Forest opening with a secondary road network

This paper presents the results of an analysis of the position and density of a secondary road network in the group-selection management system. The research was conducted in the economic unit Prosara in the north west of the Republic of Srpska. The network of skid roads in the analyzed sections was recorded using the GPS devices Garmin GPS 60 and Garmin Map 62st, and the analysis software package used was ESRI ArcInfo 10.1. Adhering to the general guidelines, the slope of skid roads was analyzed within six predefined intervals: 0-12 %, 12-16 %, 16-20 %, 20-30 %, 30-40 % and over 40%. Relative openness with a secondary road network was determined for a maximum distance between the skid roads of 130m and it ranged from 82.62 % to 96.37 %. Such openness was classified as very good and excellent. Together with all factors related to stand and terrain characteristics, it appears that in all the compartments, the density of the secondary network of skid roads is adequate for the application of a skidder with a winch, without extending above the maximum length of the winch rope. Out of the total length of analyzed skid roads, 24% is within an appropriate slope interval for a planned conversion to truck roads, whereas 37 % is the maximum slope from the ecological point of view. The average terrain slope for the whole analyzed area is 26.4%. Such moderately sloping terrain is suitable for the construction of skid roads with low investment and small environmental impact. Due to their specific configuration, the main skid roads were designed along the ridge, while the secondary and tertiary skid roads most often separated from them at the maximum slope, forming an irregular fish bone shape