Quality of beech, birch and oak wood from stands growing on post-agricultural lands

This study assessed the quality of birch, beech, and oak for timber production on former agricultural land. All sample plots for the selected species had the same forest habitat type. All measured trees had already reached the age of felling. Thus, beech was over 120 years old, birch was over 70 years old, and oak was over 140 years old. On each plot, the same morphological features were measured for all trees: diameter at breast height, tree height, height of the first dead branch, height of the first live branch, and crown base. Based on collected data the length and percentage of the trunk suitable for industrial purposes were calculated. In general birch and beech trees from former agricultural land were higher, but had thinner trunks, when in oak reverse observation were noticed. Tree trunks from former agricultural lands have app. 7% shorter knots-free trunk section. The bigger different between forest and former agricultural land was noticed in case of the oak – 14%, then beech – 5% and birch – 1%. Considering the morphological characteristics of the trees and quality indicators, we showed that all species could be used for the afforestation of former agricultural lands to produce high-quality wood for future industrial purposes. However, it should be noticed, that in general calculated standing volume was lower on former agricultural land.

Wood density and annual ring width of pedunculate oak from stands grown on former agricultural land

The main aim of this study was to determine differences in basic density and average annual ring width of pendulate oak wood collected from trees grown on former agricultural land and on forest land, using a dimensional method. The experiment was carried out in the western part of Poland, near to Poznan, which is in the central part of the European range of pedunculate oak. In our study the average basic density was 0.528 g.cm-3, and the value for former agricultural land was lower by 0.026 g.cm-3 than that for forest land. Differences in basic density values between these two land types were statistically significant. The average annual ring width in samples collected from forest land in our study was 2.48 mm, samples from former agricultural land were characterized by wider average annual rings. The results suggest that there are significant differences in quality of wood from former agricultural land and from forest. However, from view of wood quality and applications the difference is not important.

The gradient of wood moisture within-stem of sessile oak (Quercus petraea (matt.) Liebl.) in summer

In the xylem of growing trees water fills both free spaces in the cell walls and capillary spaces. For this reason its share in the tree mass is very high. As a result transport of logs obtained from fresh-felled trees is mainly equivalent to the transport of contained water. The primary aim of this study was to determine wood moisture content in growing trees in the selected season of the year. Absolute moisture content of tested wood was established at 62.4%. Average moisture content in heartwood was 60.6% and it was lower by approx. 6% from moisture content in sapwood. Moisture content of the oak heartwood is high, similar to central part of the trunk of non – heartwood species. It is an exceptional situation in comparison to heartwood species, particularly conifers.