Prediction of Static Bending Properties of Eucalyptus Clones Using Stress Wave Measurements on Standing Trees, Logs and Small Clear Specimens

In this study, we used both nondestructive and destructive methods for assessing solid wood properties in six Vietnamese grown Eucalyptus clones at 6 years after planting. We measured stress wave velocity in standing sample trees (SWVT), logs (SWVL), and small clear specimens (SWVS) obtained from the trees and logs, and to measure static properties, we used MOE-modulus of elasticity and MOR-modulus of rupture. The highest average MOE and MOR were detected in clones 3 and 5, suggesting that these clones might be more appropriate for breeding programs focused on improving wood quality of Eucalyptus grown in Vietnam. Mean MOE and MOR of the lumber had significant (p < 0.001) relationships with SWVT (r = 0.61 and 0.53, respectively) and SWVL (r = 0.76 and 0.71, respectively). Stress wave velocity measurements of both standing trees and logs can be useful for further segregating Vietnam's Eucalyptus timber resource based on MOE and MOR. For the small clear specimens, the best prediction of stiffness (dynamic modulus of elasticity (MOEd)) was obtained when both SWVS and air-dry density (AD) were used. The coefficient of correlation between MOE and MOEd was 0.93.