Abstract
In order to prevent attacks by subterranean termites (Coptotermes formosanus Shiraki and Reticulitermes speratus Kolbe) on buildings and to control their potential, artificial traps were buried around the buildings of an electric power plant. The attacking activities of the termite in and around the traps were monitored by the detecting of acoustic emission (AE) generated by the feeding. of the termites. The trap has a cylindrical form with 600 mm height, 300 mm in diameter, consisted of wood sticks of Japaness red pine for forage in its center and slender polystyrene foam sticks surrounding the wood sticks. In eight traps of the ten set, termite activities were observed, especially a larger number of termites were found in the three of them. The traps were renewed every one or two months. The amount of termites coming into inhabiting the traps decreased drastically after the first renewal in June 1993, however it varied slightly in the following two and a half years. The amount of termites in the traps has increased during the period when the traps were kept without exchanging since September 1995. The estimated distribution of the termite attack in the plant was shown that the termite activity was restricted signifi-cantly by the installing and renewal of the artificial traps and any other serious additional attacks were found in and near the buildings during the test period. AEs generated by the feeding activities were monitored continuously by piezoelectric AE sensors attached to the sticks in the trap or on the wood bait stakes near the trap. The rates of AEs detected varied according to the feeding activities which are associated with the number of termites in the trap and the temperature conditions.
