Radial wood variation in some anatomical features in Aspidosperma quebracho blanco

Abstract

Radial wood variation patterns of Aspidosperma quebracho blanco, one of the most important species of the Dry Chaco Region, and their influence on wood quality are reported in this study.
Pattern variations of wood density, frequency and diameter of pore vessels and fiber length were examined using sites, trees and radial distances as sources of variation.
Univariate analysis was performed using a nested design, with random effects on sites and trees and fixed distances to the pith. Variance Components were estimated by Restricted Maximum Likelihood.
The results indicated that distance to the pith was the most important source of variation for the traits studied.
With the exception of fiber length, the wood anatomical features measured were not affected by site. Fiber length increased rapidly from pith to bark and defined the juvenile wood zone. Wood density was not found to be a good indicator of wood quality due to the great variability between trees.