Using hybrid models to develop silvicultural prescriptions for Eucalyptus nitens

A structural model was developed for Eucalyptus nitens from relationships b etween leaf area and stand structural components, and was incorporated into an existing hybrid model. The existing hybrid model combines the process-b ased site productivity model PROMOD and an empirical stand growth model NIT GRO. The modified hybrid model was used to predict the development of stand leaf area and stand crown length in 17 diverse stands of E. nitens in Tasm ania. We demonstrate how the model can be used to identify sites for prunin g based on site productivity, predicted leaf area index, and minimum piece sizes required at the end of the rotation; schedule pruning operations base d on height to the base of the green crown and leaf area index, and schedul e thinning to minimise height-related windthrow risk. (C) 2001 Elsevier Sci ence B.V. All rights reserved.