Pines in the forests of Slovenia represent approximately 6% of the forest stock. Previous studies have shown that there are differences between habitats, in both the incidence of scale and intensity of heartwood, as well as the width of the growth rings. No accurate data is possible to find in the literature on the relationship between the shares of early and late wood and dimensional stability. Dimensional stability is important in terms of the use of wood and does not depend only on the enzymatic processes and on the portion of extractive substances in the wood. With fine grinding and high-resolution scanning we made high quality photos of the surfaces of wood on the cross-sections of Scotch pine. With computer software NIS-Elements and Image-J we calculated the ratios between early wood and late wood and we measured the width of the growth rings. Then we used gathered data of each sample to study correlations between widths of the growth rings and percentage of early and late wood, between density and dimensional stability. Results showed that the trees from better growth sites had wood with wider growth rings and bigger percentage of early wood. Wood with bigger percentage of early wood had smaller shrinkage and lower density. Wood samples with narrower growth rings had bigger percentage of late wood, bigger volume shrinkage and bigger transverse anisotropy. At the same time the wood with narrower growth rings has higher density and better mechanic properties correlated to higher density.
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