João Gabriel Missia da Silva

RADIAL GROWTH DYNAMICS OF Khaya ivorensis TREES FROM EXPERIMENTAL PLANTATION

1 Received on 02.12.2016 accepted for publication on 23.01.2018. 2 Universidade Federal do Espírito Santo, Programa de Pós-Graduação em Ciência Florestal, Jerônimo Monteiro, ES Brasil. E-mail: <denise_soranso@hotmail.com> and <j.gabrielmissia@hotmail.com>. 3 Universidade Federal do Espírito Santo, Centro de Ciência Florestais e da Madeira, Jerônimo Monteiro, ES Brasil. Email: <grazividaurre@gmail.com> and <jtsilva@npd.ufes.br>. 4 Universidade Federal de Goiás, Setor de Engenharia Florestal, Goiânia, GO Brasil. E-mail: <mpchagas@gmail.com>. 5 Universidade Federal Rural do Rio de Janeiro, Departamento de Produtos Florestais, Seropedica, RJ Brasil. E-mail: <latorraca@hotmail.com>. *Corresponding author.

QUALITY OF REACTION WOOD IN Eucalyptus TREES TILTED BY WIND FOR PULP PRODUCTION

: This study aims to evaluate the quality of normal, tension and opposite wood of eucalyptus trees lengthwise, in straight and inclined stems,affected by wind action. It also aims to explain the pulping parameters resultant from the quality of the wood. The trees were grouped into four tilt ranges, ranging from 0 to 50o, and the basic density, chemical composition of the wood, and performance in kraft pulping were assessed. Normal and tension wood had similar basic densities; while for opposite wood, the densitywas lower, being responsible for a decrease in reaction wood density. The chemical composition of the wood was influenced by the presence ofreaction wood in the stem. Tension and opposite wood showed lower levels of extractives and lignin and higher holocellulose content when compared to normal wood, with favorable woodquality for pulping. The increase in holocellulose content and thereduction of lignin and extractives content contributed positively to a more delignified pulp andreduction of the Kappa number. However, after cooking the reaction woodunder the same conditions as those of normal wood,reaction wood pulping tends to have a lower screen yields. Due to differences in basic density and chemical constituents between opposite and normal wood, it is recommended not to designate the opposite wood as normal wood.