RESISTANCE OF THERMALLY MODIFIED Eucalyptus grandis W. Hill ex Maiden WOOD TO DETERIORATION BY DRY-WOOD TERMITES ( Cryptotermes sp.)

ABSTRACT There are currently in operation at least 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: natural 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 (IPT, 1980). Similarly to the European processes of thermal modification, the Brazilian VAP HolzSystem e ® was not effective to improve wood resistance to dry-wood termites attack, at least in the evaluated conditions.