METHOD OF EVALUATING LOGS TO PREDICT PROPERTIES OF LUMBER OR VENEER PRODUCED FROM THE LOGS

A method is disclosed for evaluating logs to predict structural properties and/or warp tendency of lumber or veneer that might be produced from a given log. The method can be used in a forest stand, sorting yard or merchandiser, on-line in a sawmill, or at other locations along the route from forest to mill. It enables decisions whether a log should be directed to a sawmill for lumber manufacture or for other applications such as timbers, veneer, or pulp chips. Log taper has been found to correlate with both stiffness and warp propensity of lumber cut from a given log. A high amount of taper leads to warped lumber and low stiffness lumber or veneer. The correlation with taper is highest if it is measured over the full stem length of the harvested log, before it is bucked to sawmill size or veneer blocks. Other geometric features of the log, such as sweep or cross section irregularity, can be combined with taper in a multivariate regression equation to increase accuracy of prediction. This can readily be accomplished in a conventional scanner used in a sort yard or sawmill.