WOOD RESEARCH Volume 70, Number 1, 2025
DOAN VAN DUONG, VAN HUNG HOANG, MASUMI HASEGAWA, and EVGENII SHARAPOV

THE INFLUENCE OF TREE AGE AND RADIAL POSITION ON THE STRESS-WAVE VELOCITY AND TIMBER PROPERTIES OF PINUS MASSONIANA LAMB. PLANTED IN VIETNAM

The main objective of this study is to investigate the influence of tree age and radial position on the structural properties, asair-dry density (AD), modulus of rupture (MOR), modulus of elasticity (MOE) and the stress-wave velocity measured on small specimens (SWVS). Results of analysis showed a highly significant effect of age and radial position on the SWVS, AD, MOR, and MOE. Stress-wave velocity and wood property traits tend to increase with increasing tree age. The SWVS and selected wood properties near the pith were significantly lower than those near the bark. Mean MOR and MOE of the timber had significantly (P<0.001) relationships with SWVS (r = 0.75 and 0.91, respectively), although in the case of MOR a model based on AD alone is slightly better (r = 0.79). There were also significant relationships of acoustic velocity measured in standing trees (SWVT) with mechanical properties measured destructively in small specimens implying that stress-wave method has a good potential for measuring static bending properties of P. massonianaplanted in Vietnam

WOOD RESEARCH Volume 64, Number 6, 2019
Kyriaki Giagli, Hanuš Vavrčík, Marek Fajstavr, Kateřina Novosadová, Antonín Martiník, and JAKUB ČERNÝ

Stand factors affecting the wood density of naturally regenerated young silver birch growing at the lower altitude of the Czech Republic region

The objective of this study was to investigate the basic wood density (ρk) of the silver birch (Betula pendula Roth.) trees in relation to the stand structure. This research was conducted in three stands of different structure and ages, located in the region of the lower part of the Jeseníky Mountains in the Czech Republic. In total, 71 healthy dominant silver birch trees were randomly selected. Two samples (cores) were taken per tree for performing the tree-ring width analysis and ρk determination. We found that the average ρk of the three examined stands ranged from 471.8 to 494.6 kg. m-3. The older trees showed a high variation of the ρk. The age of the tree and stem diameter positively influenced the ρk. Nevertheless, it was noted that the slenderness ratio had a negative influence on the ρk. Overall, the prediction of wood density using stand and tree characteristics, even when the management history records are available, remains a complex hypothesis.