ONGITUDINAL AND RADIAL VARIATION OF EXTRACTIVES AND TOTAL LIGNIN CONTENTS IN A CLONE OF Eucalyptus grandis W.Hill ex Maiden x Eucalyptus urophylla

The objective of this work was to determine concentrations of extractives and total lignin along with their radial and longitudinal variations in wood from a clone of Eucalyptus grandis W.Hill ex Maiden x Eucalyptus urophylla S. T. Blake at age six years. Longitudinal samples were taken at 2%, 10%, 30% and 70% of the commercial height of trees, and radial samples were taken from each longitudinal position, the number of samples depending on the diameter of each disk. Results led to the conclusion that, overall, concentrations of extractives and total lignin in the wood tended to decrease with increasing distance from the pith and tended to increase in portions closer to the tree base.