Assessment of the differences between juvenile and mature woods of Populus alba trees in the longitudinal and radial axes of the stem

The aim of this study was to evaluate the differences between juvenile and mature woods of Populus alba trees in the axial and radial directions of the stem. For this purpose, three stands of P. alba trees were randomly chosen and cut from at their diameter at breast height. Three disks with a thickness of 5 cm were taken at three different height levels along the tree stems. The specimens were sequentially cut in the radial position according to the ISO standards method. The results indicated that there are significant differences in the physical and biometric features of P. alba trees in the longitudinal and radial axes of the stem. As the height from the base of the tree to the top of the stem increased, the oven-dry density, basic density, and fiber biometric factors decreased. Moreover, as the distance from the pith to the bark increased, the oven-dry density, basic density, and fiber biometric factors increased. The microscopic study represented that the P. alba is a semi-ring-porous hardwood with distinct growth ring boundaries, simple perforation, homogenous rays, and alternative inter-vessel pits.