The influence of thinning on the proportion of peeler, sawtimber, and pulpwood trees in loblolly pine plantations

Data from a long-term, region-wide thinning study were used to examine the proportion of pulpwood, sawtimber, and peeler quality trees in unthinned, once-thinned, and twice-thinned plantations. Results suggest that the thinning treatments have had a significant influence on the product distribution in these stands over the 21-year history of the study. Proportional odds modeling methods were used to develop equations for predicting product proportions from dbh, the basal area before and after thinning (thinning intensity), and the number of thinnings imposed.