The variability of certain macrostructural features and the density of grand fir (Abies grandis Lindl.) wood from selected stands in southern Poland

The paper presents the results of investigations into the variability of certain features of the wood macrostructure, such as the width of the annual ring, the share of late wood, and the relative density of the wood of grand fir, growing in four stands in southern Poland. The trees under investigation were 30-35 years old. The research material consisted of incremental cores sampled from trial trees with the use of a Pressler borer. The examined wood features were analysed in sections, each one comprising five annual rings. The rings were given numbers, sorted in an ascending order from the trunk circumference. The mean values of the analysed features were as follows: the annual ring width – 4.38 mm, the share of late wood - 35.39%, the relative wood density – 0.354g·cm-3. It was established that the wood of grand firs growing on less fertile soils had significantly narrower annual rings and higher wood density than those on more fertile soils.