METHOD OF EVALUATING LOGS TO PREDICT WARP PROPENSITY OF LUMBER SAWN FROM THE LOGS

A method of predicting warp of lumber that might be sawn from any given log is disclosed. The method involves measurement of stress wave velocity in the tree stem. A scan is then made to define the exterior geometric configuration of the log. In particular, measurements relating to lack of longitudinal axis linearity (sweep) or irregularity of cross sections of the log are important. Stress wave values and selected geometric parameters are entered into a multivariate regression equation to predict warp propensity of lumber that might be sawn from the log. The equations are originally derived by examination of a representative population of logs of the particular species and locale and measurement of warp in lumber sawn from the logs. Logs determined to produce warp prone lumber can be isolated and used to produce other products such as timbers or plywood where warp is not as critical.