A Thinned/Unthinned Loblolly Pine Growth and Yield Simulator for Planted Cutover Site-Prepared Land in the Mid-Gulf South

Abstract

Abstract The components and structure of a thinned/unthinned growth and yield simulator, developed by the MSU Growth and Yield Cooperative, for planted loblolly pine (Pinus taeda L.) on cutover site-prepared land are generally described. Prior to the first thinning, a three-parameter Weibull diameter distribution recovery system supported on the arithmetic-mean, quadratic-mean, and minimum-stand diameters is employed. At the first thinning, or if an initial tree list is supplied as input, a parameter-free least squares adjustment, diameter moment recovery system is used to allocate mortality and diameter growth to the elements of the tree list. Because thinnings from below essentially are equivalent to heavy competition mortality, the parameter-free mortality allocation procedure is adapted for allocating thinned trees to the before-thinning tree list. Copies of a PC-compatible computer program implementing the model can be obtained by writing to the senior author. South. J. Appl. For. 16(2):70-75.