Predicting Basal Area Growth in Thinned Slash Pine Plantations

Abstract Long-term remeasurement data were used to evaluate different approaches to predicting basal area growth in thinned slash pine ( Pinus elliottii Engelm.) plantation plots at four locations in South Africa. These data clearly indicated that a single projection model for both unthinned and thinned plantation plots, based on basal area and age at the start of the projection period, was inappropriate. Precision of the basal area projections were improved significantly when a measure of the thinning intensity was included in this model. Even better projections of basal area growth in thinned plots were obtained with an approach that utilized an index of suppression to modify the expected growth in comparable unthinned stands. Forest Sci. 31:731-741.