Prediction of the mechanical properties of lumber by stress-wave velocity and Pilodyn penetration of 36-year-old Japanese larch trees

Solid Wood Properties Assessed by Non-Destructive Measurements of Standing European Larch (Larix decidua Mill.): Environmental Effects on Variation within and among Trees and Forest Stands

“…For both measurements, reaction wood due to slope and wind direction played a role and PP, which only assess the outermost rings, will be more influenced by recent growth differences [18], while SWV measurements better reflect long-term growth, density, and stiffness differences due to slopes. Our observations regarding varying SWV values on the four tree sides corresponded to findings published by Ishiguri et al [17] and Paradis et al [16]. For Japanese larch (Larix kaempferi (Lamb.)…”

“…The inner structure of wood, notably, the length and position of fibres, is likely a source of variation as opposed to a difference in wood density [51]. Other authors found only weak correlation between density and velocity [7,12,17,48], which was also confirmed with our data. The presence of knots and damages on the other side of a tree exhibited little influence on acoustic velocity in white spruce (Picea glauca (Moench) Voss), because the dilatational wave tended to take the fastest path of travel around local defects [52].…”

“…Carr. ), Ishiguri [17] reported on the effects of the measuring position, namely direction and height above ground level. Carter et al [49] discussed the presence of reaction wood in stands with steep slopes as well as its impact on velocity measurement.…”

“…Using our empirical data on PP as a simple estimator of wood density as well as the SWV from the two stands, B3 and B16, we calculated the modulus of elasticity according to the following formula: [17] We calculated MOE for each individual tree and used average values of PP and SWV across the four measurements.…”

“…In particular, the stress-wave velocity, i.e., the time it takes a stress wave to travel a fixed distance through the tree, was found to be a valuable parameter, strongly correlated to the modulus of elasticity (often referred to as wood stiffness) and wood density [15,16]. Together, Pilodyn penetration and stress wave velocity measurements on standing trees are simple and effective non-destructive methods for assessing required data in terms of indirect tests of wood quality [7,[16][17][18].…”