Wood characterization of Salix. 1: Influence of the site, clone, age and sampling height

Abstract

The wood of two Salix clones cultivated in the Delta of Paraná River in Argentina was characterized according to their optical properties, chemical composition, basic density, tyloses content and health condition, analysing variations in terms of site, clone, age and sampling heighAmerican willow showed more cellulose content, higher density and less lignin, extractives and tyloses than the 131/27 hybrid. The wood of the last one had the smallest damaged area in the disks and the highest brightness values. The most appropriate site for both clones was the one less affected by flood. Brightness, L* and basic density increased, whereas deteriorated area decreased from bottom to tip within each tree. The tyloses percentage also decreased, both in vertical and horizontal directions. Six different types of wood were defined. Between them, "grey-coloured rings", result of flood, and "dark zone", may be considered similar to "healthy wood". Three types of stains were responsible for the main changes in the wood analysed. The "brown stains" showed low brightness and high tyloses, but the darkest one showed high lignin and low cellulose contents. The "light-brown stain" had the highest alkali-soluble substances contenThe "blue stain" showed low brightness and high extractives content.