Resistance of thermally modified Eucalyptus grandis W. Hill ex maiden wood to deterioration by dry-wood termites /Resistencia da madeira modificada termicamente de Eucalyptus grandis W. Hill ex maiden ao termita de madeira seca Cryptotermes sp

• Published in: Ciência florestal 2016-04, p.671
• Main Authors: Batista, Djeison Cesar, Nisgoski, Silvana, Oliveira, Jose Tarcisio da Silva, de Muniz, Graciela Ines Bolzon, Paes, Juarez Benigno
• Format: Article
• Language: Spanish
• ISSN: 1980-5098; 1980-5098

There are currently in operation five major European industrial processes for wood thermal modification. They improve wood's dimensional stability and decay resistance, but are not efficient against termites attack. In fact, there is little research about the effect of thermal modification on wood resistance to termites, whether subterranean or dry-wood termites. The aim of this study was to evaluate the effect of the Brazilian process of thermal modification (VAP HolzSysteme®) on the resistance of Eucalyptus grandis wood to attack by Cryptotermes sp. dry-wood termites. Five treatments were tested: untreated eucalypt wood, thermally modified eucalypt wood at three final temperatures (140, 160 and 180°C) and pine wood (control). The attack was evaluated in terms of mass loss, mean score of wear grades, number of holes and termites mortality, according to a Brazilian method proposed by the Technological Research Institute of Sao Paulo. Similarly to the European processes of thermal modification, the Brazilian VAP HolzSysteme® was not effective to improve wood resistance to dry-wood termites attack, at least in the evaluated conditions. Keywords: thermal modification process; VAP HolzSysteme®; termites attack. Existem atualmente cinco principais processos de modificacao termica em operacao na Europa, que aumentam a estabilidade dimensional e a resistencia da madeira a biodeterioracao, porem, nao sao eficientes contra o ataque de termitas. Na verdade, existe pouca pesquisa a respeito do efeito da modificacao termica da madeira na resistencia a biodeterioracao por termitas, sejam subterraneas ou de madeira seca. O objetivo desta pesquisa foi avaliar o efeito do processo brasileiro de modificacao termica VAP HolzSysteme® na resistencia da madeira de Eucalyptus grandis ao ataque de termitas de madeira seca Cryptotermes sp. Para tanto, foram testados cinco tratamentos: madeira nao tratada de eucalipto, madeira de eucalipto modificada termicamente a tres temperaturas finais (140, 160 e 180°C) e madeira de pinus (controle). O ataque foi avaliado em termos de perda de massa, escore medio das notas do desgaste, numero de orificios e mortalidade das termitas, de acordo com o metodo proposto pelo Instituto de Pesquisas Tecnologicas de Sao Paulo. Semelhante aos processos europeus de modificacao termica, o processo brasileiro VAP HolzSysteme® tambem nao foi eficaz para melhorar a resistencia da madeira de eucalipto ao ataque das termitas de madeira seca, pelo menos nas co