Data from 1.213 trees of Eucalyptus grandis x E. urophylla hybrids were collected between 1988 and 1994 from the Aracruz Celulose S.A. commercial plantation in the State of Espírito Santo, Brazil. Data on stand productivity and macronutrient concentration in four tree components (leaf, branch, stembark and stemwood) were used to determine the reference values of nutrient concentration by the methods of Mathematical Chance and DRIS. The formula of Jones and the population distribution based on age and selection of the relation between elemental concentrations by the F test were used in the calculation of DRIS indices. Critical levels were obtained using the DRIS method, by the following processes: determining the mean nutrient concentration in the nutritionally balanced and productive (optimum critical level) eucalypt stands; and by graphs (critical-level graph). The mean concentration proved to be a promising method, even when compared to the Mathematical Chance method. This latter method was appropriate mainly for the determination of the optimum range, which could be used as minimum and maximum limits for the range of nutrient sufficiency in productive trees.
Eucalyptus; optimum levels; critical levels; sufficiency range