Among the wood properties that are affected by innumerable factors, such as growth conditions, environmental and silvicultural practices, the density stands out, which influences all other technological properties. The traditional methods used for density determination use wood samples, consuming time and making the process economically undesirable. Thus, the objective of this study was to establish model equations for the determination of basic density of Pinus taeda L., as a function of wave propagation velocity, moisture content of wood, tree diameter and height. Seventy-two trees from commercial plantations at 15 and 16 years of age were evaluated. In each tree, the impulse tomography was applied in the DBH cross-section. The trees were felled and sectioned in short logs at 0%, 33%, 66% of commercial height, in which the tomography was applied, to obtain the stress wave velocity (V), and a disc was removed to determine the basic density (BD) and moisture content (MC), according to ABNT standards NBR 11941 and NBR 14929, respectively. Several statistical models were tested to adjust the basic density of standing trees. As results, it was found for all situations analyzed, except for height at 66%, the best equation was: ln BD = β₀ + β₁*V² + β₂*(V²*MC) + β3*(V*MC²) + β4*MC². The best models were those that had the variable wood moisture content present in an isolated way. However, for the conditions of this forest stand, the stress wave velocity could not explain the wood basic density, since the variation of this variable was extremely small.

01 - Use of a non-destructive technique to estimate the wood basic density in standing trees