Variability in chemical composition of narrow-leaved ash (fraxinus angustifolia Vahl. ssp. Pannonica soó & simon) in regard to its age and possition inside the tree

Abstract

The evaluation of wood chemical composition is of the great importance for the optimal utilization of wood raw material. Certain application areas of wood and wood products are closely related to the chemistry of wood components. Variability of the chemical composition of wood is common for the same wood species and even inside the single tree. Such variations may have significant effects on the properties of related wood material. Hence, this work presents a detailed evaluation of chemical characteristics of juvenile (10 years) and mature wood samples (72 years) of the Narrow-leaved Ash. The samples were taken from the tree trunks at three different heights. The contents of cellulose and lignin were higher in the mature wood samples. The cellulose content decreased with the increase in height of the tree trunk, while the vertical position had no significant effect on the lignin content. The content of the extraneous material, dissolved in toluene-ethanol solution, was significantly lower in the samples of juvenile wood, and it decreased with the increase in height. However, the same samples had the higher content of ash and the extracts dissolved in hot water, in regard to the samples of mature wood.