The objective of this work was to evaluate the variability in the resistance to dry-wood termites of Eucalyptus grandis wood from commercial stands of four different ages (10, 14, 20 and 25 years old). Two logs were cut from sixteen different trees, four of each age. Six pairs of samples were taken from the most recent heartwood of a central board of a log. Each pair of samples was put in contact with 40 dry-wood termite individuals, Cryptotermes brevis. Samples of Pinus elliottii, a highly susceptible species, were also offered to the insects at the same time and under the same laboratory conditions in order to compare the results. The assay lasted for 45 days. After this period, the remaining insects were counted and the wood samples were inspected to determine number of holes, damage etc. It was found that 10-year-old wood samples were the most severely attacked, being the damage similar to that suffered by the control. There was no significant difference between levels of damage suffered by the other three treatments (trees of 14, 20 and 25 years of age); in all cases the damage caused by the insects was considered very serious.
Eucalyptus grandis; dry-wood-termite; Cryptotermes brevi
