Study object – Spruce wood the time is ripe fact – finding in Trakai state forest enterprise, Trakai and Semeliskes forestry stalls. Study aim – Research spruce round wood data kind’s variation consistent pattern and make spruce steams sort models of structure. To reveal basic Lithuanian forest market’s development tendencies, determine main factors, characterizing dynamics of round wood kinds. Study methods – In tests on several groups of Norway spruce (Picea abies (L.) Karst.) comprising more than 309 trees in total, the method detected dynamics of round wood kinds have been evaluated of method correlation analysis with high accuracy. We validated the method both by measurements and by finite element modeling and simulations. Study results – It has been analyzed Norway spruce’s round wood structure models of Trakai state forest enterprise during 2003 – 2005 years. It has been estimated each round wood kind’s simulation with tabulation and evaluated kind of round wood for diameter fluctuation.

Aim of the work – to analyze the regularities of quality rates variation and to make the evaluation models of birch assortment structure, concerted with Europe Union standard’s requirements. Object of the work – semi mature and mature birch forests. During research there were used measurement data of birch stems quality rates (diameter, bark thickness at full stem length) and round wood defects. Methodology of the research – there were measured pruned birch stems, filled in the model wood card, indicating the forest and the model wood characteristics. After this empirical database was structured and normatives were made, which allow to evaluate the volume of timbers of various diameter and high trees A, B, C and D quality classes, paper wood, firewood and waste wood. Results of the research – birch - grove felling sorting – grading structure prognosis method was prepared. Sorting – grading tables in MS “Excel” computer program make its essence.