On the "Delimusa" section 86, economic units "Krivaja" on ŠPP "Olovsko", was built experimental plane ordinary fir with nine provenience. We analyzed the number of needle-per-cm by provenience, the dimensions of the needle by provenience needle and participation by age. For all the properties variance analysis, as in Duncanov test showed statistically significant differences between studied provenience. The results we obtained can be used for differentiation silver fir, or to estimate the population variability.

For rational forest management and realization of the bio-technical planed activities on time it is inevitable to build widely branched network of forest roads of sufficient density. Simultaneously with this it is necessary to take into consideration that roads are not only significant for production aspect of forest but also for many other aspects: ecological, sociological, environmental etc. The best solution for forest opening is achieving the best possible forest accessibility with lowest possible investment. The targeted result in forest opening is optimum forest roads network. Optimization of forest roads network is achievable by mathematical formula of minimizing total costs. Methods for optimization of forest roads network by means of computers analyze numerous factors and have different approach to resolving forest opening. In this paper the analysis has been done in order to get areas suitable for construction of forest truck roads. Influence factors taken into account for analysis areas follows: normal stock, depth of the soil and terrain slope. After evaluation of areas which are more or less suitable for forest truck roads for each specific influence factor it has been got aggregate thematic map in which areas suitable and non suitable for construction of forest truck roads have been given.