Growth resulting from the variation and combination of models of Chapman-Richards and Silva-Bailey applied to Leucaena leucocephala (Lam.) of Wit

The main objective of this work was to develop new growth models for forest resources, applied to (leucena) [Leucaena leucocephala (Lam.) of Wit], based on the biological hypotheses proposed by Chapman-Richards and Silva-Bailey. The experiment of the leucena was carried out in the Experimental Station of the Agricultural and Liverstock Research Company of Pernambuco - IPA, in the municipal district of Caruaru - PE. Five hundred and forty four trees of Leucaena leucocephala (Lam.) of Wit were used, with 20 measures along the time. It was compared new growth models resulting from the combination and variation of the Chapman-Richards and Silva-Bailey models, as well other models used in forest resources. For the selection of the final equations, the fit of index, standard error of estimate and the graphic distribution of the residues were used. Results show that new models were as good as Chapman-Richards and Silva-Bailey and other tested. Therefore, any one of them can be applied to estimate the growth of leucena.