Tension wood (TW) is a reaction tissue of hardwood, differing from normal wood (NW) by its anatomical, chemical, physical and mechanical properties. The presence of high proportion of tension tissue with its specific behaviour lessens the quality of wood, and causes difficulties manufacturing it. We investigated differences among the same physical properties between tension and normal beech wood (Fagus sylvatica L.). We detected explicitly large longitudinal shrinkage in TW distinguishing it from NW. Volumetric, radial and tangential shrinkage in TW were smaller than those in NW. A little greater density in TW was not statistically significant. Differential swelling in radial (qR) and tangential (qT) directions did not show differences between TWand NW. Coefficients of swelling in radial (hR), tangential (hT) directions as well as sorption coefficient (s) were significantly reduced in TW. Equilibrium moisture content of TW in all hygroscopic ranges was lower in comparison to that of NW. Average fibre saturation point (FSP) was lower in TW for 1.9 % than in NW. Diffusion coefficient in TW was smaller than in NW, but the difference was statistically not significant.
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