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Colonization of hosts by bark beetles is generally mediated by aggregation pheromones. Species competing for the same resource can limit interspecific interactions and maintain reproductive isolation by using different pheromones. In the southern United States, 3 sympatric species of Ips breed in pine hosts, each with a different pheromone blend. Ips avulsus (Eichhoff) uses ipsdienol and lanierone; Ips calligraphus (Germar) uses ipsdienol, cis-verbenol, and trans-verbenol; and Ips grandicollis (Eichhoff) uses ipsenol. Different species can also minimize cross-attraction by using different enantiomeric ratios of the same pheromones. Studies on the enantiomeric ratio of ipsdienol used by I. avulsus have come to contradictory conclusions in part because of geographic and seasonal variation. There is growing evidence that semiochemical context, in the form of different co-baits used in trapping experiments, may also play a role in the responses of I. avulsus to enantiomeric ratios of ipsdienol. We conducted a trapping study at 2 locations with traps baited with (+)-ipsdienol or racemic ipsdienol and co-baited with ipsenol, lanierone, or both ipsenol and lanierone. We found context-dependent effects of both lanierone and ipsenol on the response of I. avulsus to ipsdienol. We suggest that responses to different bait and co-bait combinations may have been shaped by different types of interactions such as the absence of conspecifics or a related species, or the presence of beneficial or antagonistic interspecific interactions. [ABSTRACT FROM AUTHOR]

In 2006, we evaluated the effects of combining lures releasing pine host kairomones (ethanol + α-pinene) with lures releasing bark beetle pheromones (ipsenol + ipsdienol) on trap catches of predators associated with bark and woodboring beetles in Florida, Georgia, Louisiana, and Virginia. Catches in traps baited with all 4 compounds were greater than those in traps baited with either binary blend for the common predators Thanasimus dubius (F.) (Coleoptera: Cleridae), Temnoscheila virescens (F.) (Coleoptera: Trogossitidae), Aulonium tuberculatum LeConte (Coleoptera: Zopheridae), and Lasconotus spp. (Coleoptera: Zopheridae). The same was true for: Enoclerus nigripes (Say) (Coleoptera: Cleridae) at 2 of 3 locations; Platysoma cylindricum (Paykull) (Coleoptera: Histeridae) at 3 of 4 locations; and Corticeus spp. (Coleoptera: Tenebrionidae) at 2 of 6 locations. In contrast, the addition of ethanol + α-pinene to traps baited with ipsenol + ipsdienol reduced catches of Platysoma attenuatum LeConte (Coleoptera: Histeridae) at 2 of 4 locations. [ABSTRACT FROM AUTHOR]

In 2007-2008, we examined the flight responses of Monochamus titillator (F.) complex [M. titillator, Monochamus carolinensis (Olivier), and any possible hybrids], Monochamus scutellatus (Say), Monochamus clamator (LeConte), Monochamus obtusus Casey, and Monochamus mutator LeConte (Coleoptera: Cerambycidae) to multiple-funnel traps baited with and without host volatiles and bark beetle pheromones. Experiments were conducted in mature pine (Pinus) stands in Alberta (Canada), and Arkansas, Arizona, California, Florida, Idaho, Michigan, Montana, New Hampshire, North Carolina, Ohio, Oregon, Tennessee, Utah, and Wisconsin (United States). At each location, traps were deployed in 10 replicate blocks of four traps per block. The trap treatments were: 1) blank control; 2) ipsenol and ipsdienol; 3) ethanol and α-pinene; and 4) a quaternary blend of ipsenol, ipsdienol, ethanol, and α-pinene. All five species or species complex of Monochamus preferred traps baited with the quaternary blend over all other treatments. The consistency of these results across such a large geographic area suggests that similar selection pressures may be acting on Monochamus spp. in pine forests, regardless of variation in stand composition and climatic conditions. Our results suggest that multiple-funnel traps baited with the quaternary blend of ipsenol, ipsdienol, ethanol, and α-pinene may be highly effective for monitoring various Monochamus spp. in pine forests of North America, and may have utility in trapping and detection programs in North America and overseas. [ABSTRACT FROM AUTHOR]

In 2006, we examined the flight responses of 43 species of longhorn beetles (Coleoptera: Cerambycidae) to multiple-funnel traps baited with binary lure blends of 1) ipsenol + ipsdienol, 2) ethanol + α-pinene, and a quaternary lure blend of 3) ipsenol + ipsdienol + ethanol + α-pinene in the southeastern United States. In addition, we monitored responses of Buprestidae, Elateridae, and Curculionidae commonly associated with pine longhorn beetles. Field trials were conducted in mature pine (Pinus pp.) stands in Florida, Georgia, Louisiana, and Virginia The following species preferred traps baited with the quaternary blend over those baited with ethanol + α-pinene: Acanthocinus nodosus (F.), Acanthocinus obsoletus (Olivier), Astylopsis arcuata (LeConte), Astylopsis sexguttata (Say), Monochamus scutellatus (Say), Monochamus titillator (F.) complex, Rhagium inquisitor (L.) (Cerambycidae), Buprestis consularis Gory, Buprestis lineata F. (Buprestidae), Ips avulsus (Eichhoff), Ips calligraphus (Germar), Ips grandicollis (Eichhoff), Orthotomicus caelatus (Eichhoff), and Gnathotrichus materiarus (Fitch) (Cureulionidae). The addition of ipsenol and ipsdienol had no effect on catches of 17 other species of bark and wood boring beetles in traps baited with ethanol and α-pinene. Ethanol + α-pinene interrupted the attraction of lps avulsus, I. grandicollis, and Pityophthorus Eichhoff spp. (but not I. calligraphus) (Curculionidae) to traps baited with ipsenol + ipsdienol. Our results support the use of traps baited with a quaternary blend of ipsenol + ipsdienol + ethanol + α-pinene for common saproxylic beetles in pine forests of the southeastern United States. [ABSTRACT FROM AUTHOR]

In 2006, we tested the responses of the small southern pine engraver, Ips avul.rus (Eichhoff) (Coleoptera: Curculionidae), to multiple-funnel traps baited with (+)-, (-)-, and (±)- ipsdienol. Three experiments were conducted in Georgia with all traps co-baited with one of the following lure combinations, respectively: experiment 1, ipsenol; experiment 2, lanierone and (-)-α-pinene; and experiment 3, ipsenol, lanierone, and (-)-α-pinene. Ipsdienol and lanierone are aggregation pheromones used by I. avulsus, whereas ipsenol is an aggregation pheromone used by the eastern fivespined ips, Ips grandicollis (Eichhoff), a sympatric species also breeding in pines. In all experiments, the highest catches of I. avulsus were obtained in traps baited with (±)-ipsdienol. The relative attractiveness of (+)-ipsdienol varied across the three experiments. When traps were co-baited with ipsenol, lanierone, and (-)-α-pinene, catches of I. avulsus in traps baited with (+)- ipsdienol were high and no different from those in traps baited with (±)-ipsdienol. When traps were co-baited with lanierone and (-)-α-pinene, catches in traps baited with (+)-ipsdienol were lower than those in traps baited with (±)-ipsdienol by ≈40%, whereas catches were reduced by ≈95% when traps were co-baited with ipsenol alone. We hypothesize that the observed variation in enantiospecific responses of I. avulsus to ipsdienol may be explained by variation in semiochemical context (i.e., different co-baits among the experiments) or seasonal variation. [ABSTRACT FROM AUTHOR]

We conducted four behavioral choice tests in stands of mature lodgepole pine in British Columbia, from 1988 to 1991, to determine the dose-dependent responses of Orthotomicus latidens (LeConte) and Ips pini (Say) to their respective pheromones. Dose-dependent responses were exhibited by I. pini to (±)-ipsdienol and lanierone, with trap catches directly proportional to pheromone release rates. We found differences in sex ratio of I. pini in their responses to ipsdienol but not lanierone. There was no dose-dependent response exhibited by O. latidens to its pheromone, (±)-ipsenol, with or without the presence of the host kairomone, (-)-β-phellandrene. The bark beetle predator, Enoclerus lecontei (Wolcott), showed a dose-dependent response to lanierone. Thanasimus undatulus (Say) was attracted to ipsenol in a dose-dependent fashion only when traps were also baited with β-phellandrene. Neither T undatulus nor E. sphegeus (F.) exhibited dose-dependent responses to ipsdienol. [ABSTRACT FROM AUTHOR]