Background and purpose: Need for distilling wood is rather significant on the wood market in Republic of Srpska. Delivering of distilling wood is done according JUS standard. Purpose of this research was to explore how much this standard is appropriate for present assortment of wood which deliver and use as distilling wood, and what are main problems. Material and methods: Research was conducted at the premises of the company "Destilacija" a.d. Teslic. It was selected samples of distillation wood in a random manner, so as to check accuracy of conversion factors stated in the delivery note. Subject of interest were loads with one-meter log wood for distillation. Conversion coefficients are determined by using xylometry method and dendrometric method. Results and conclusions: Conversion factor based on xylometry varies considerably between 0.45-58. Results lead to the conclusion that appliance of officially prescribed conversion factor leads to over estimation of delivered distillation wood. Also results of dendrometric measurements and calculating of volume show that conversions factors are significantly lower than those one obtain with the xylometry 0.36-0.52. Main reason for that may laying in the fact that measurements was done according to JUS which prescribes measurement with rounding down for diameter (round centimeters) and length (round decimeters). Dendrometric measurement according JUS is not appropriate for assortments from the category of staked wood. Conversion coefficients must be determined for different moisture content. One solution for described gap may be shift to weight scaling. In that case mistakes caused by measurement could be avoided but it must be considered moisture of wood also. Wood for distilling should be as dry as much as possible before use, around 20 % moisture content.

Planning of forest harvesting operations is one of the key elements of successful forest management. The integration of modern tools and traditional forestry procedures is something that must be done in contemporary forestry. This research investigated the use of multicriteria decision support (AHP) and GIS in choosing the optimal harvesting system for predominantly selection cutting forest management on the example of two Forest Management Units (FMU). Results showed that AHP could be easily integrated into GIS using the extAHP tool and its results could be of help, along with other input data, in choosing the optimal harvesting system. Spatial analysis of raster data in GIS gives a comprehensive insight into the stand and terrain characteristics and shows the relative share of the area proposed for each system. In FMU »Kozara–Mlječanica«, the harvesting system chainsaw-skidder had the highest relative share with 44% of the area, meaning that it is almost the only harvesting system in current use, followed by chainsaw-forwarder (36%), chainsaw-cable yarder (19%), and chainsaw-adapted agriculture tractor (AAT) (1%). The system harvester-forwarder was not used at all, which is understandable considering that FMU »Kozara–Mlječanica« has a higher average slope and higher diameter of trees to be cut than FMU »Prosara«, where harvester-forwarder system accounts for a significant 36% of the area. The dominant system in FMU »Prosara« was chainsaw-forwarder (42%), followed by chainsaw-cable yarder (17%), chainsaw-skidder (4%) and chainsaw-AAT (1%). It should be noted that the presence of chainsaw-skidder system is insignificant. It is replaced by the system chainsaw-forwarder. Traditional harvesting system chainsaw-skidder, which prevails in Bosnia and Herzegovina, should be upgraded with the new technologies and methods. Using tools like multicriteria decision support and GIS could be of great help in that process.

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IzvodTransport sortimenata, prije svega oblog drveta, je najskuplji proces u proizvodnji. On se sastoji iz tri faze: primicanje, privlačenje i prevoz kamionima. Sa stanovišta troškova transporta najvažnije su prve dvije faze transporta. One u prvom redu zavise od udaljenosti mjesta sječe stabala od šumskog puta ili srednje transportne distance privlačenja i zato je određivanje njene vrijednosti veoma važno sa stanovišta planiranja otvorenosti šuma. Srednja transportna distanca je jedan od pokazatelja otvorenosti. Vrijednost srednje transportne distance privlačenja može se dobiti na više načina: mjerenjem na terenu ili pomoću programskih paketa zasnovanih na GIS-u. Srednja transportna distanca dobijena u Izvođačkim projektima za odjele 19, 20, 21, 22, 37, 47, 48 i 22/1 u Privrednoj jedinici "Prosara", iznosi 600 m. Primjenom ArcGIS 10 programskog paketa dobijena je prvo geometrijska transportna distanca privlačenja koju smo množili sa faktorom korekcije koji za date terenske uslove iznosi 1,38. Na taj način smo dobili stvarnu srednju transportnu distancu privlačenja koja je 590 m. Između ove dvije daljine privlačenja nema statistički značajne razlike i prema tome srednja stvarna transportna distanca privlačenja koja je određena pomoću ArcGIS-a 10, može biti korišćena za određivanje učinka skidera. Uporedili smo stvarnu i geometrijsku srednju transportnu distancu privlačenja i dobili da faktor korekcije iznosi 1,57. Prema tome prosječni faktor korekcije za nizijsko-brdske terene iznosi 1,475.Ključne riječi: faktor korekcije, privlačenje, srednja transportna distanca privlačenja, transport Sječom i izradom dobijaju se šumskodrvni sortimenti, proizvodi koje je potrebno transportovati do prerađivačkih kapaciteta ili krajnjih potrošača. Transport se sastoji iz tri faze: sakupljanje ili primicanje sortimenata, privlačenje i prevoz sortimenata. Primicanje ili sakupljanje sortimenata je faza transporta koja podrazumijeva sakupljanje drvne mase pored sekundarnih šumskih komunikacija (vlake, traktorski putevi ili trasa žičare). Privlačenje sortimenata se vrši po sekundarnim šumskim komunikacijama do šumskog puta ili međustovarišta na njemu, pri čemu se teret uglavnom vuče po vlaci. Prevoz podrazumijeva prevoz sortimenata kamionima po šumskim i javnim putevima do prerađivačkih kapaciteta ili potrošača. Transport sortimenata je veoma značajan i najskuplji dio proizvodnje šumsko drvnih sortimenata. Prema Sokolović & Bajrić (2013) troškovi transporta iznose oko 80% ukupnih troškova proizvodnje drvnih sortimenata. Troškovi prevoza kamionima prema troškovima privlačenja traktorima i troškovima

background and purpose: Optimisation of skid road network is very important in forest utilisation because transport is considered to be the most expensive part of timber production. Designing forest traffic infrastructure means positioning its location in the forest area using traditional or modern methods. Many factors influence the skidding costs, and winching distance is one of them. The use of modern techniques gives an opportunity to forest practitioners that simulate different network variants and choose the most appropriate ones. Materials and Methods: The research object is Compartment 27, which belongs to Forest Administration Unit "Prijedor", with the area of 46.72 ha. Investigation is divided into the phase of field work and the phase of designing secondary forest road network variants in the office. Field work includes the traditional and Global Positioning System (GPS) marking of trees for cutting and the creating of Geographic Information System (GIS) database. In relation to spatial distribution of trees for cutting, skid roads and skid trail networks are laid by using the GPS. The new scondary road network is laid in the field and compared with three simulated variants of secondary road network that are laid by ArcGIS 10.3. Secondary road network is planned by using Network Analyst tools and Shortest path method that is based on Dijkstra's algorithm. These variants are simulated based on different average winching distances of 10, 20 and 30 m. results: The area of the compartment is divided into two transportation zones. Total length of the secondary road network designed in the traditional way is 4816 m, thus achieving the secondary openness of 103 m•ha -1 . In simulated Variant I, with winch pulling distances of 20 m, the total length of secondary roads is 5590 m with costs of 14352.62 €, in Variant II with winching distance of up to 40 m length of secondary roads it is 3228 m with costs of 7426.78 €, and in Variant III with winch rope length of up to 60 m, the length of roads is 2219 m, with costs of 4400.89 €. The achieved mean skidding distances are relatively similar in all variants. When taking into account the average length of the winch rope, considering all three new-design variants, it can be said that there is almost no difference in productivity and skidding costs. conclusions: Mean winching distance has influence on skidding costs, but only in variants where mean skidding distance is decreasing. Smaller winching distance is justified only from the aspect of work humanization. Small differences in skidding costs between variants have no practical significance except for large quantities of wood assortments.