SITE INDEX EQUATION FOR NOTHOFAGUS-PUMILIO PATAGONIAN FOREST

Nothofagus pumilio is the most important native timber species in the Patagonian forest. Since there is no site index equation for lenga for est, we set as our aim to provide such an equation. One hundred trees were selected (along ten sites) for stem analysis and the data obtaine d were used in the nonlinear regression analysis. The constrained Weib ull-type site index model was selected, because it showed the best sta tistics; it also has the property of H=S at index age. Base age at 60 years was selected, and a range for SI60 of 9.8 to 23.22 m of total he ight was obtained. The use of this equation provides some of the infor mation required for different management regimes and silvicultural sit uations in lenga forests.