System of equations for yield and growth of Pinus taeda including prune variables

Abstract

It were adjusted stand yield functions and dinamic growth models, that compose a compatible system of equations, that include regressors variables associated with prune intensity, beside age, stand density and site index. The data set come from a trial in a Pinus taeda L. plantation, with ages between 4 and 9 years. The response variables analyzed were basal area and volume per hectare. For both variables the models obtained produced lower production and young growth values when the prunes were intensified. Also, it were obtained more precision and a slightly better adjusted quality than equations with excellent statistic behavior without prune variables. The utilization of predictive area basal functions allows to obtain results for quadratic mean diameter according to prune intensity. These functions could be easy employed as a tool to decide when and how much of green branches prune in relation with the production objective. The obtained models appear interesting to develop new regional growth simulation programs of Pinus taeda that include prunes applied in intensive silvicultural systems of forest production.