Characterisation of eucalypt wood from trees with dieback for production of Kraft pulp

Abstract

Dieback, resulting from abiotic stress, compromises the development of trees and the quality of wood. The objective of this work was to characterise the wood and cellulosic pulp produced from young eucalypt wood with dieback. Eucalyptus grandis × Eucalyptus urophylla three-year-old trees from commercial plantations in the municipality of Estreito, Maranhão, Brazil were analysed. Height and diameter at breast height were measured, and the volume of trees (with and without stress) was estimated. The basic density, anatomical elements, chemical properties and parameters related to the production of cellulosic pulp were analysed in discs taken along the trunk of 15 trees with dieback and 15 without the stress. The basic wood density did not change, however, the anatomical elements, chemical composition of the wood and the commercial volume differed between the trees with or without dieback. The pulp produced from stressed wood presented low cooking yield and low viscosity, increased production chemical consumption and overall consumption of wood.