UDK: 630*37:630*4     Hauling of heavy and voluminous load (wood) partially through forest wastelands and partially on built roads makes this the most expensive phase, which is also technically the most challenging and most damaging for the forest eco-system. Although it is clear that the realisation of this phase in forest harvesting cannot be completed without certain forest damage, in expert and scientific circles there is general consent that by careful planning and execution in forestry, this damage can be brought down to an ‘acceptable’ level.   One of the reliable indicators of stand damage is the amount of mechanical damage resulting from forest harvesting operations. This damage can be ascertained rather easily and correctly, and the environmental and economic consequences of mechanical damage of standing trees are better known than those resulting from damaging saplings or the soil. (Martinić, 2000).  Pertaining to this, this paper presents the measuring and analysis of mechanical damage to standing trees as a result of hauling trees using the cable skidder ‘Timberjack 225 A’ in the forest unit 17,  Management Unit ‘Gornja Stavnja’, Forest Management Company ‘Gornjebosansko’. The amount of damage was analysed, the place where it occurred on the tree, the level of damage and the surface of the inflicted damage. All the stated analyses were carried out for two ways of skidding wood using a winch (falling and ascending).  Results show, among others, that the stand damage expressed in the percentage of damaged trees of the total tree count is 15.41%, which is the upper limit Martinić (1993) ascertained for this phase of forest harvesting, including the variability of working methods and techniques. Almost half of the damage is stated in the first third of the distance between the skidder path and transport boundary, with the largest amount of damage occurring on the most valuable part of the tree (butt end), especially during slope skidding.

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UDK 630*38:551.311.21          625.711.84:551.311.21 Tractor roads are often, due to un-implementation of appropriate rehabilitation measures, exposed to erosion processes of various intensity. These processes can be particularly expressed upon completion of forest harvesting works if natural conditions also have such character which favors intensification of erosion process. Intensification of erosion processes on tractor roads in post-exploitation period most often occur in cases when surface water appears on ruts. More intensive coverage occurs in cases when tree crowns do not cover tractor roads, i.e. if larger opening (of forest crop) is in close vicinity of tractor road, which enables larger presence of light and more intensive vegetation growth. This document applies erosion process intensity degree method and assessment of degree of coverage or coverage by litter. For assessment we used a scale from 1 to 5 (REBULA, 1991). Erosion intensity degree on observed locations goes from 1,86 to 3,73. Coverage of tractor roads by grass vegetation or coverage by litter is in range from 4,91 to 1,86.

Chainsaw is the main tool for work in a phase of wood felling and processing of forest harvesting in BiH. The aim of the research was to determine fuel and lubricant consumption of the chainsaws Husqvarna 365 and Dolmar PS – 7310 in the phase of felling and processing of wood assortments at the area of P.J. Forest Office „Zavidovići“, forest compartment 203. The volumetric method was applied for the measurement of fuel and lubricants consumption, with precise determination of fuel and lubricant quantity in chainsaw tanks. In total 140 trees of the sessile oak were felled (70 trees with chainsaw Husqvarna 365 and 70 trees with chainsaw Dolmar PS – 7310) during the research. The diameter at the breast height of felled trees ranged from 15 to 84 cm, while tree height ranged from 10,3 to 37,2 m. The total volume of processed assortments was 180,11 m³. The average fuel consumption per m³ processed assortments was 0,306 L/m³ for trees felled by chainsaw Husqvarna 365 which is for 0,042 L/m³larger in comparison to chainsaw Dolmar PS – 7310 with average fuel consumption of 0,264 L/m³. The average lubricant consumption per m³ processed assortments was 0,102 L/m³for trees felled by chainsaw Husqvarna 365 which is for 0,012 L/m³ larger in comparison to chainsaw Dolmar PS – 7310 with average lubricant consumption of 0,09 L/m³. Considering conducted research it can be assumed that there are differences in fuel and lubricant consumption between this two type of chainsaws for considered working conditions, but differences are not statistically significant.

The primary network of forest roads consists of public and forest truck roads. Public roads in one forest area have been mainly built due to needs of local communities, access to rural areas, the development of tourism, recreation and so on. Forest truck roads have been built and maintained by those who manage forests (the forest management), while public roads have been managed by the Directorate for Roads of the Federation of B&H and cantonal and local governments. In the last twenty years, the sector for wood assortments transport in the Federation of B&H is in charge of the private transport operators which use vehicles of large capacities and high axle loads for the purpose of transport of as large as possible quantities of wooden mass per time unit. Due to this fact, the roads have deteriorated faster. The accelerated deterioration of the roads used for the transport of wooden assortments imposes the need for the allocation of larger funds for their maintenance. Due to the increasing damages on the roads the prohibitions of use of some public roads for wooden assortments transport occur more frequently. The aim of the research is to determine the total length of public roads which open Forest Management Units of Sarajevo Canton (FMU of SC) and to investigate the possibility of using these categories of roads for forestry. For examination and analysis possibilities of using public roads for wooden assortments transport qualitative research-polls methods have been applied within the framework of the key representatives of the target groups such as forestry and the local community. In the questionnaire, two sets of questions were specified, the first one which is designed to determine the possible existence of problems of using public roads for transport of wooden assortments and possible causes of occurrence of the problems. The second group of questions gives some of the possible solutions for solving the problems of using public roads for the purpose of transport of wood assortments. The results of the survey show that the share of public roads for opening forest truck roads of Canton Sarajevo amounts 44.94%. The given results illustrate that the cases of prohibition of use of public roads for wood assortments transport are rare. The largest proportion of respondents (65%) pleaded that there are no problems (conditions) for using public roads within their territory. A share of 32% of respondents said that there are some requirements for the use of public roads for the transport of wood assortments in their territory and those are mostly demands that FMU covers the costs of maintenance of these roads. A share of 58% of respondents gave the answer that those requirements originate from self-organized groups of citizens. A share of 42% of respondents gave the answer that these requirements originate from the local community (municipalities and lower levels). In the second group of questions, where the proposal for resolving the problems of wood assortments transport in case of inability of use the existing pub...