This study aimed to develop a prognosis system for growth and yield of Pinus taeda L. to simulate and evaluate several management regimes for the production of multiple use clearwood to analyze the economic feasibility for several sites, spacings, and wood discount rates and prices, based on owned and rented land plantations. The developed model was based on the compatibility of stand basal area model and diametric class model. The Weibull distribution was chosen to allow the prognosis for several strata and stand ages. A thinning simulator is then applied to obtain the desired remaining stand. A new prognosis is then made and a new thinning simulation applied. This procedure is repeated up to Pinus sp. the final cutting, using the SPPinus (Prognosis Yield System for Pinus sp.). For the economic analysis, two scenarios were compared, using various numbers, periods and thinning intensities, based on different initial planting intensities and various yield levels. A sensitivity analysis of the economic performance was conducted for each management regime, considering three discount rate levels, two wood price levels and the option of owing or renting land. It was concluded that: the model proposed did not present bias in volume and growth estimates; the management regime with a pre-commercial followed by two commercial thinnings should be adopted; renting land for Pinus sp. plantation is economically feasible but owing land is more profitable; the initial spacing should be of 833 trees/ha; and pruning improves wood quality that increases wood price, that will eventually enhance the economic feasibility of management regimes.
Growth; yield; simulation; thinnings; prunings
