ELIMINATION OF STRUCTURE-INFESTING TERMITE POPULATIONS USING PRECISION TARGETING AND BAITING TECHNIQUES

When whole-structure fumigation is not a feasible option due to construction or environmental restrictions, a localized application of insecticides, or spot treatment, into active foraging galleries of termites has been used as an alternative. Because the foraging galleries for drywood termites are relatively small, injection of liquid insecticides into active infestation may kill the entire colony (Scheffrahn et al. 1997). In severe infestations, however, multi colonies of drywood termites may be present within a building. The challenge for drywood termite control using spot treatments, therefore, is the detection of all active colonies within a structure. Foraging galleries of a subterranean termite colony may extend up to 100 m from a site of active infestation (Su & Scheffrahn 1988). Spot treatments using liquid insecticides only kill a small portion of the colony. Because the nest structures of a subterranean termite colony are interconnected by foraging galleries, bait containing slow-acting insecticides may be applied through sites of active infestation to impact the entire colony population. Both in-ground (Su 1994, Su et al. 1995) and above-ground (Su et al. 1997) baiting methods incorporating the chitin synthesis inhibitor, hexaflumuron, were successfully used to eliminate colonies of subterranean termites, R. flavipes, and C. formosanus. Application of baits using above-ground stations is well suited for remedial control of structure infesting populations of subterranean termites. Baits are placed directly over active foraging sites within a structure so that foraging termites can readily feed and transfer baits to nestmates. Recent development in detection technologies such as the acoustic emissions detector (Scheffrahn et al. 1993, 1997) also provides an additional tool for precision targeting in bait application. Control of the Formosan subterranean termite, C. for osanus, in historic Cabildo complex, French Quarter, New Orleans, provides an example of precision targeting and baiting using the acoustic emissions detector and spatial distribution analysis