EN
High unit costs of mechanized timber harvesting are a major obstacle for the development of this process in Poland. Apart from that, other important factors include forests structure, work organization and principles of the forest utilisation in the State Forests. Fragmentation and dispersal in the superintendence economic tasks related to the acquisition of wood affect the reduction of the degree of use of the machine during the working day. In this study, we paid particular attention to the harvester runs between successive tasks and between tasks and bases of the night stopover. The above−mentioned organizational factors can substantially affect the performance of the machine and their potential reduction could improve the economic efficiency of the use of harvesting machines in the Polish forests. The simulation calculations assumed fixed total area covered by the work of logging and fixed total amount of acquisitions. The parameters of the variables in the calculation was the number of tasks performed and the number of bases of the night stopover. Change in the previous parameter was clear with the volume of a single task and the distance between them. The paper discusses the results of research on the impact of these parameters on the multioperational machine operating efficiency. Reducing the number of jobs (increasing their size) causes significant increase in harvester efficiency. In extreme cases, it may be up to about 20%. The article also points to the possibility of better organization of work and thereby the economic effects of the use of harvesting machines in selected forest areas. Deciding on the organization of work in a specific forest district one should however also take into consideration principles of the forest utilisation.