Three major species of Ips bark beetles (Coleoptera: Scolytidae) in the southeastern United States, 1. avulsus (Eichoff), 1. calligraphus (Germar), and 1. grandicollis (Eichoff), attack all species of pines in their range, sometimes causing significant tree mortality (Thatcher, 1960 USDA Forest Service Occasional paper 180, 25 pp.) Coincident with region-wide drought, pine mortality due to Ips has been severe throughout the southeastern United States in recent years. For example, losses in 1999 were estimated at about U.S. $13 million dollars, second only to the southern pine beetle in value lost from insect-caused mortality (Report on losses caused by forest insects, Sou thern Fores t Insec t Work Con fe rence , 2000) . Before effective monitoring, management or research programs can be developed and implemented for Ips beetles in the Southeast, effective lures must be identified for each species. lpsdienol has been identified as an aggregation pheromone for 1. avulsus (Vite et al. 1972, Can. Entomol. 104: 1967-1975; Hughes 1974, J. Insect Phys io l . 20 : 1271-1275) . In add i t ion , the enant iomer ic compos i t ion o f ipsd ieno l appears to be important. The primary aggregation pheromone for 1 . avu/sus was identified as (-)-ipsdienol, while its antipode was found to be an antiaggregant (Vite et al., 1972; Skillen et al., 1997, USDA Forest Service, FHTET-96-15). However, Birgersson et al. (1995, Proc. of a Joint IUFRO Working Party Conference, 1994, pp. 12-18) successfully captured 1 . avulsus using racemic ipsdienol in combination with lanierone, a strong synergist to ipsdienol for attracting 1. phi (Teale et al., 1991, J. Chem. Ecol. 17: 1159-l 176). Seybold (1995, J. Chem. Ecol., 21: 9951016) also found that 1 . avulsus produced primarily (+)-ipsdienol. Thus, managers and researchers alike are uncertain about which lures should be used to trap this species. Synthetic ipsdienol lures are available from a commercial source in 97% (-) and 50% (-) (= racemic) formulations (Phero Tech, Inc., Delta, BC). Because the 97% (-) lure costs about 5 times more than the racemic lure (about U.S. $30.00 versus $6.00)