Chemical attractants tested against the Australian bush flyMusca vetustissima (Diptera: Muscidae)

A number of chemical compositions known to attract several synanthropic and pest fly species were tested against the Australian bush flyMusca vetustissima, a severe and persistent pest of man and domesticated and wild mammals. A standard composition containing small quantities of trimethylamine and indole, blended with large amounts of ammonium sulfate and anchovy meal, showed good attractancy against this fly. Deletion of ammonium sulfate did not significantly alter attractancy. Similarly, incorporation ofn-butyric acid and linoleic acid into the formulation did not alter attractancy, nor did addition of several carbonates and bicarbonates. Skatole, a closely related compound to indole, decreased attractancy significantly. In all the tests, the attractant compositions lured greater number of females than males. The attractancy of the standard composition was studied and compared with equal amount of fresh cattle dung. Chemical attractants lured bush flies and not dung beetles, while dung attracted both flies and beetles. The dung resource was 4.6 × more attractive to flies than the standard attractant composition. This suggests that there are other chemical attractants emanating from dung that warrant isolation and identification work. Nevertheless, the chemical attractants studied here provide a starting point for further investigations. The ratio of female to male flies attracted to humans was greater than the ratio of flies attracted to chemicals. The sex ratio of flies netted from human host was 3.0, while the sex ratio of flies attracted to chemical attractants was 1.8. The preponderance of females attracted to both sources was probably due to physiological requirements of the sexes.     

Caribbean fruit fly,Anastrepha suspensa (Loew), attraction to host fruit and host kairomones

Extracts of 22 fruits were tested for their attractancy toAnastrepha suspensa (Loew), the Caribbean fruit fly. Box-orange, calamondin, carambola, cattley guava, loquat, and Surinam-cherry were about equal in attractiveness to males and females. Nine synthetic chemicals, including four found in box-orange ripe seed, were attractive to females. Five synthetic chemicals, including two in box-orange ripe seed, were attractive to males. Farnesol,-phellandrene, and 3-carene were highest in attractiveness to both males and females. Females were more attracted than males to 12 synthetic chemicals. These data suggest that host chemicals serve as attractants and that female and male specific attractants and traps could be developed from host kairomone data. These data also suggest that the volatilization of chemicals from water may play an important role in kairomone biology.     

Field evaluation of chemical attractants against the flyFannia femoralis (Diptera: Muscidae)

Four chemical compounds previously shown to be attractants toHippelates eye gnats and houseflies were evaluated againstFannia femoralis (Stein). Two of the compounds, trimethylamine hydrochloride andn-butyric acid, were determined to be the principal attractants against this fly. A composition containing trimethylamine hydrochloride (yielding trimethylamine in presence of water),n-butyric acid, and an anchovy meal inert carrier proved highly attractive. To evaluate the practical use of the synthetic fly attractant (SFA) formulation, a large-scale trial over an entire poultry ranch was implemented using SFA formulation and a sugar toxicant (as a killing agent) in specially designed traps. Within 2 weeks after initiation of SFA-toxicant treatments, significant reduction inF. femoralis population from the pretreatment level occurred. This high level of reduction prevailed during the remainder of the treatment period.     

Compounds modifying the activity of two sex attractants for males of the pea moth,Cydia nigricana (F.)

(E)-10-Dodecen-1-yl acetate (E10–12Ac) and (E,E)-8,10-dodecadien-1-ylacetate (E,E8,10–12Ac) are sex attractants for males of the pea moth,Cydia nigricana (F.). Thirty-two structurally related compounds with chain lengths of 9–14 carbon atoms were exposed withE10–12Ac orE,E8,10–12Ac in traps in the field to investigate their influence on the activity of the attractants. Only alchols and acetates unsaturated at C-8, -9, or -10 greatly influenced moth captures. (Z) and (E)-8-dodecen-1-ol were weak synergists forE10–12Ac but no synergists forE,E8,10–12Ac were found. (Z) and (E)-8-dodecen-1-yl acetate and (E,E)-8,10-dodecadien-1-ol inhibited bothE10–12Ac andE,E8,10–12Ac while (E)-10-dodecen-1-ol, 10-dodecyn-1-ol, (Z) and (E)-9-dodecen-1-yl acetate, (Z)-10-dodecen-1-yl acetate, and undecyl acetate inhibited only the former attractant.     

Behavioral Response of Lygus hesperus to Conspecifics and Headspace Volatiles of Alfalfa in a Y-Tube Olfactometer

The western tarnished plant bug, Lygus hesperus Knight, feeds and develops on a variety of weeds in the spring, with later generations moving to alfalfa and cotton where severe damage to reproductive structures can occur. A synthetic attractant for monitoring or mass-trapping L. hesperus, or the identification of potential attractants for natural enemies, would be useful tools for integrated pest management programs. Studies investigated the response of naive and experienced fifth-instar and adult L. hesperus to odors associated with conspecifics and alfalfa, Medicago sativa L. Fifth-instar L. hesperus responded to all plant/insect combinations, whereas female L. hesperus only responded preferentially to vegetative and flowering alfalfa where conspecifics had fed for 24-72 hr, and to vegetative alfalfa where conspecifics were added approximately 30 min before the test began. Males were not attracted to headspace volatiles from any of the alfalfa treatments. Analysis of headspace volatiles showed that (E)-2-hexanal, (Z)-3-hexen-l-ol, alpha-pinene, (Z)-3-hexenyl acetate, (E)-2-hexenyl acetate, limonene, (Z)-ocimene, (E)-beta-ocimene, linalool, (3E)-4,8-dimethyl-1,3,7-nonatriene, and (E, E)-alpha-farnesene are emitted from both vegetative and flowering alfalfa. Indole and (3E, 7E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene were only detected in flowering alfalfa. Damage to alfalfa by L. hesperus increased emissions of (Z)-ocimene, (E)-beta-ocimene, (E)-beta-caryophyllene, and (E, E)-alpha-farnesene, while beta-pinene, myrcene, methyl salicylate, and (3E, 7E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene were only detected from damaged plants. Thus, individual or mixtures of these alfalfa volatiles may be useful as attractants for capturing nymphs and adult females of L. hesperus in the field.     

Attraction ofCarpophilus spp. (Coleoptera: Nitidulidae) to synthetic aggregation pheromones and host-related coattractants in Australian stone fruit orchards: Beetle phenology and pheromone dose studies

Synthetic aggregation pheromones ofCarpophilus hemipterus (L.) andCarpophilus mutilatus Erichson were field tested during a 10-month period in southern New South Wales stone fruit orchards to determineCarpophilus spp. phenology and the effect of two pheromone doses on attraction. Aggregation pheromones synergize the attraction of host volatiles toCarpophilus spp. Four major species,C. hemipterus, C. mutilatus, C. davidsoni Dobson andC. (Urophorus) humeralis (F.), were trapped, with greater numbers of each species inC. hemipterus pheromone/fermenting whole-wheat breaddough-baited traps, than in dough-only-traps. InC. mutilatus pheromone/ fermenting-dough-baited traps, onlyC. mutilatus andC. davidsoni responded in greater numbers than to dough-only traps. Beetles first appeared in traps in late September (early spring) when daily maximum temperatures averaged 17.5C. Trappings reached a peak during October and declined to very low levels in November–December (late spring-early summer). Numbers trapped of all species increased during February–March (late summer–early autumn), presumably due to the presence of abundant host resources (ripening and fallen fruit), and continued at high levels until May (late autumn). An 18-week study demonstrated significantly greater responses byCarpophilus spp. to 5000-g than to 500-g doses of C.hemipterus andC. mutilatus pheromones. Greatest responses to 5000g were recorded forC. hemipterus andC. mutilatus responding to their own pheromones (increased attraction over dough alone of 259x and 21.2x respectively). Implications of the study and the potential for using synthetic aggregation pheromones for managingCarpophilus spp. populations in Australian stone fruit are discussed.     

Single and blended maize volatiles as attractants for diabroticite corn rootworm beetles

Synthetic maize volatiles and analogs dispensed singly and blended were tested for attractiveness to western (WCR, Diabrotica virgifera virgifera) and northern corn rootworm beetles (NCR, D. barberi) in maize fields. Newly identified attractants included syn-benzaldoxime, especially for NCR, and -caryophyllene for WCR females. (±)-Linalool was more effective than was (–)-linalool. Myrcene, (+)--pinene, and (–)--pinene were unattractive. Adding methyl salicylate to (±)-linalool, (+)--terpineol, or -ionone appeared to synergistically increase capture of WCR females, but dispensing the terpenes in binary blends did not. Dose–response data for methyl salicylate, (±)-linalool, and a blend of both compounds confirmed the synergy. -Caryophyllene, but not (–)--pinene, added to the latter blend produced a further synergistic increase in WCR female capture that did not vary with sesquiterpene dose from 1.0 to 100 mg. Indole addition to the same blend caused an increase in WCR female captures indicative of synergy, assuming that each did not individually lure different segments of the WCR female population. The green leaf volatiles (Z)-3-hexenyl acetate and (Z)-3-hexen-1-ol were unattractive alone and had no influence on efficacy of traps baited with 3.3 mg each of (±)-linalool, methyl salicylate, and -caryophyllene. The latter mixture captured about half as many WCR females as did 10 mg of 4-methoxycinnamaldehyde, a potent WCR attractant standard. Substituting -ionone for (±)-linalool yielded a ternary blend that captured more beetles than did the aldehyde and was unaffected by aldehyde addition. Olive oil, which has been used to sustain attractant volatilization, did not affect captures. The results show that the blending of maize volatiles has the potential to greatly improve efficacy of lures having promising applications in corn rootworm population management.     

Sex pheromone components and calling behavior of the female dermestid beetle,Trogoderma variabile Ballion (Coleoptera: Dermestidae)

Females of the dermestid beetle,Trogoderma variabile Ballion, exhibit a diel pattern of calling behavior. A potent sexual excitant and attractant for the male beetles can be collected on Porapak Q during aeration of female beetles, but cannot be detected in extracts of macerated females. The attractant has been identified as (Z)-14-methyl-8-hexadecenal. Of the five additional compounds previously identified as attractants in otherTrogoderma species, only two were found; (Z)-14-methyl-8-hexadecen-1-ol is present in extracts of macerated female beetles, but not in extracts of Porapak Q, and -caprolactone is present in extracts of Porapak Q. Three collection procedures were necessary to ensure that all the pheromone components had been isolated. Synthetic (Z)-14-methyl-8-hexadecenal elicits attraction and sexual arousal inT. Variabile males.Mention of a commercial or proprietary product in this paper does not constitute an endorsement of that product by the USDA.     

TrappingDendroctonus brevicomis Changes in attractant release rate,dispersion of attractant,and silhouette

A sticky trap with 3 m² surface area was modified by changes in attractant release rate, vertical dispersion of the attractant, and addition of a tree trunk silhouette to the trap axis. As attractant release rate increased, the number ofDendroctonus brevicomis caught at the source of attractant and at 1.5 and 5.2 m above ground on two vertical silhouettes 4.5 m away increased. In one experiment, more beetles were caught at a dispersed source of attractant than at a point source. Fewer beetles were caught at the lower traps on the two outlying silhouettes when a silhouette was at the source, than when no silhouette was at the source. As attractant release rate increased, the catch of a predator,Temnochila chlorodia, increased at the source.Coleoptera: Scolytidae.Based in part on a thesis submitted by Paul E. Tilden to the University of California, Berkeley, in partial fulfillment of the requirements for the Master of Science degree in entomology, December 1976. These studies were supported by the Forest Service, U.S. Department of Agriculture, and in part by the Rockefeller Foundation and a joint grant (NSF GB-34718/BMS 75-04223) from the U.S. National Science Foundation and the U.S. Environmental Protection Agency to the University of California. The findings, opinions, and recommendations are not necessarily those of the funding agencies or the University of California.Mention of trade names is for information only and is not an endorsement by the funding or sponsoring agencies.     

Influence of pheromone chirality on response byOryzaephilus surinamensis andOryzaephilus mercator (Coleoptera: Cucujidae)

The response of the sawtoothed grain beetle,Oryzaephilus surinamensis (L.), and the merchant grain beetle,O. mercator (Fauvel), to synthetic racemic and chiral macrolide aggregation pheromones was assessed in pitfall olfactometers.O.mercator utilizes theR enantiomers of (Z)-3-dodecen-11-olide and (Z,Z)-3,6-dodecadien-11-olide.O. surinamensis utilizes theR enantiomers of (Z,Z)-3,6-dodecadien-11-olide and the Synergist (Z,Z)-5,8-tetradecadien-13-olide in combination with achiral (Z,Z)-3,6-dodecadienolide. For both species, the racemates of the respective chiral pheromones were effective attractants. The respectiveS enantiomers were inactive for both species and had no effect on the biological activity of the active antipodes. No diel periodicity in responsiveness to pheromones was detected inOryzaephilus spp. reared either on a 1212 light-dark photoperiod or in darkness. Nonpheromone macrolides, naturally released in trace amounts byOryzaephilus spp., did not affect the aggregation response of either species to its pheromones when these additional macrolides were combined with the pheromone mixtures.Research supported by the Natural Sciences and Engineering Research Council of Canada, Operating Grant A3881, A0851, and A3785, and Strategic Grant G0958.     

Identification, Synthesis, and Field Evaluation of the Sex Pheromone from the Citrus Leafminer, Phyllocnistis citrella

Using male antenna as the sensing element, three electroantennographic detection (EAD)-active peaks were detected from pheromone gland extracts of the citrus leafminer, Phyllocnistis citrella. Based on gas chromatography (GC)-mass spectrometry and GC-infrared data, the semiochemicals were tentatively identified as a novel pheromone, (Z,Z,E)-7,11,13-hexadecatrienal, a previously identified attractant, (Z,Z)-7,11-hexadecadienal, and (Z)-7-hexadecenal in a ratio of 30:10:1, respectively. Identification was confirmed with synthetic compounds, which gave retention times identical to those of the natural products on three capillary columns with polar and nonpolar phases. While traps baited only with the previously identified attractant alone did not catch any males in Brazil, binary and tertiary mixtures with the major constituents caught significantly more male moths than traps baited with five virgin females. This paper and the following paper (Moreira et al.) were submitted within a few days of each other. The editors and the authors agreed that they should be published in tandem.     

(Z,Z)-7,9-Dodecadienyl acetate,sex pheromone ofEpinotia tedella clerck (Lepidoptera: Tortricidae)

(Z,Z)-7,9-dodecadienyl acetate, a reported male attractant for several New World spp. ofEpinotia, was identified as the primary pheromone of femaleE. tedella (European spruce budmoth) through chemical analysis of pheromone gland washes, the electrophysiological study of male antennal receptor types, and field-trapping tests. The washes contained this compound at a level of approximately 0.4 ng per FE, along with a similar amount of the corresponding alcohol, (Z,Z)-7,9-dodecadien-1-ol. Each compound activated its own specialized type of male receptor cell. No traces of stereoisomers or monoenes were found in the washes. In field-trapping tests conducted in stands of Norway spruce in southern Germany, (Z,Z)-7,9-do-decadienyl acetate as a single chemical proved highly attractive to maleE. tedella over a range of lure doses. The corresponding alcohol or aldehyde did not show attractivity; rather, in binary combinations with the primary pheromone, these compounds, and also the (E,Z)-7,9 stereoisomeric acetate, reduced captures. A 101 blend of (E)-9- and (Z)-9-dodecenyl acetates, reported as anE. tedella male attractant, did not reveal significant captures. No otherEpinotia spp. besidesE. tedella responded to the various 7,9-do-decadienyl test baits during this study.     

Semiochemical attractants ofDiabrotica undecimpunctata howardi barber,southern corn rootworm,andDiabrotica virgifera virgifera leconte,the western corn rootworm (Coleoptera: Chrysomelidae)

During the summers of 1984 and 1985, a variety of structurally related benzenoid compounds was evaluated in sweet corn plots as attractants for adult southern corn rootworms (SCR), western com rootworms (WCR), and northern corn rootworms (NCR). Field response to the volatiles was measured by beetle counts on baited cylindrical sticky traps placed inside the corn plots at a height of l m above ground level. SCR adults were attracted late in the season (last week of August through September, 1984 and 1985) to numerous aromatic compounds, including phenylacetaldehyde, benzyl acetone, phenethyl alcohol, phenyl acetate, indole, veratrole, methyl eugenol, methyl isoeugenol, eugenol, and isoeugenol. Although many compounds attracted SCR adults late in the season, only veratrole, phenylacetaldehyde, and chavicol were significantly active in early and middle August 1985. WCR adults were attracted to a different group of compounds, namely estragole,trans-anethole, and indole. Estragole (4-methoxy-1-allylbenzene) was an effective WCR attractant from corn tasseling in early August 1985, until the end of the trapping period in late September and early October 1985. Indole andtrans-anethole (4-methoxy-1-propenylbenzene) were less effective attractants than estragole and were most active at the beginning and/or end of the corn season. Traps baited with 100 mg of estragole caught an average of 20 times more WCR adults than unbaited control traps, and the females outnumbered the males in the baited traps. Estragole dosage tests were conducted in three sweet corn plots on different dates in 1985 and the minimum effective dose ranged between 5 and 30 mg/trap. Field tests with structural analogs revealed the importance of the site of unsaturation in the allylic side chain of estragole and the effect of different ring substituents on WCR response. The phenylpropanoids, eugenol and isoeugenol, significantly attracted NCR adults, even though these beetles were in low abundance in the test corn plots. Field tests indicate there is no cross-species response by WCR and NCR adults to their related phenylpropanoid attractants. However, in late August, SCR adults do respond to some WCR and NCR attractants (indole and several eugenol analogs). Electroantennographic analysis of SCR males revealed they can perceive peripherally a wide range of benzenoid compounds.     

Preparation and use of sex attractants for four species of pine sawflies

Sex attractants were prepared for four species of diprionid sawflies,Neodiprion lecontei, N. swainei, N. sertifer, andDiprion similis, by esterification of both synthetic and naturally occurring alcohols. For the first two species totally synthetic (racemic) compounds were attractive to males in the field. For the latter two species, none of the synthetic compounds tested were consistently attractive. For these, effective attractants were prepared by saponification and reesterification of crude extracts from female insects.Hymenoptera: Diprionidae     

Identification of sex pheromone ofTetanolita mynesalis (Lepidoptera: Noctuidae), a prey species of bolas spider,Mastophora hutchinsoni

The bolas spider,Mastophora hutchinsoni, attracts adult males of four species of nocturnally active Lepidoptera through aggressive chemical mimicry of those species' sex pheromones. Here we report the identification of the sex pheromone of one prey species, the smoky tetanolita (Tetanolita mynesalis). In sex pheromone gland extracts, only two peaks stimulated an electrophysiological response as measured by a coupled gas chromatography-electroantennographic detection analysis. These two peaks had retention times identical to (3Z,6Z,9Z)-heneicosatriene (3Z,6Z,9Z-21:H) and (3Z,9Z)-cis-6,7-epoxy-heneicosadiene (3Z,9Z-cis-6,7-epoxy-21:H), respectively, and mass spectra identical to these two compounds. It was determined that 0.23±0.16 and 0.56±0.26 ng of 3Z,6Z,9Z-21:H and 3Z,9Z-cis-6,7-epoxy-21:H, respectively, were present in pheromone gland extracts from individual females. A 1:1 blend of 3Z,6Z,9Z-21:H and 3Z,9Z-6S,7R-epoxy-21:H was an effective attractant for adult males from feral populations. Blend ratios of these two components from 2:1 to 1:2 were equally effective as attractants. Greater deviation from the optimal blends resulted in diminished trap catches. The enantiomer 3Z,9Z-6R,7S-epoxy-21:H not only was not effective in attracting males, its presence in the effective blend shut down trap catches. These results indicate that the pheromone blend consists of 3Z,6Z,9Z-21:H and 3Z,9Z-6S,7R-epoxy-21:H. This is the first report of a hydrocarbon/epoxide pheromone for a prey species of this bolas spider. Sex attractants or pheromones for the other three prey species are composed of aldehydes or acetates.     

Identification of sex pheromones of two sibling species in dingy cutworm complex,Feltia jaculifera (GN.) (Lepidoptera: Noctuidae)

The sex pheromone components of the two sibling species of the dingy cutworm that occur on the prairies of western Canada were identified in abdomen-tip extracts from calling female moths. Three monounsaturated acetates, (Z)-7-dodecenyl acetate, (Z)-9-tetradecenyl acetate, and (Z)-11-hexadecenyl acetate, are common to both species in ratios of 100133 for species A and 0.30.5100 for species B. The most effective synthetic blends for the attraction of male moths in the field consisted of these three components in ratios of 1010 at 8.8g/lure for species A and 112000 at 500g/lure for species B. The addition of Z5-12Ac to either blend reduced the catches and the addition of Z7-12OH orZ11-16OH to the three-component blend reduced the catches of species B males. The species are morphologically indistinguishable, but the identity of the males attracted to the synthetic blends could be confirmed by their antennal responses to a test blend of the three components using a GC-EAD system. Both synthetic attractant blends are competitive with females and will be useful for studying the distribution, biology, and relative abundances of the two species.Contribution no. 3879005 of the Lethbridge Research Station.     

Host Attractants for Red Weevil, Rhynchophorus ferrugineus: Identification, Electrophysiological Activity, and Laboratory Bioassay

A steam distillate from the freshly cut young bark of coconut palm Cocos nucifera was analyzed by gas chromatography, combined gas chromatography–electroantennographic detection (GC-EAD) and GC-MS to detect host attractants for the curculionid weevil Rhynchophorus ferrugineus, one of the major coconut pests in Sri Lanka. A twin FID peak consisting of a minor and a major component was shown to possess electrophysiological (EAG) activity. The minor peak was identified as -nonanoic lactone 1, while the major peak was identified as 4-hydroxy-3-methoxystyrene 2. In an EAG assay the synthetic racemic nonanoic lactone 1 did not elicit a considerable response in the antenna of R. ferrugineus, whereas the laboratory synthesized 2 showed activity. In a laboratory bioassay using a Y-type olfactometer, synthetic 1 and 2 elicited moderate attractant properties to R. ferrugineus, whereas a 1:1 mixture of the compounds showed increased attraction over that of the individual compounds.     

Ethological function of components of a sex attractant system for oriental fruit moth males,Grapholitha molesta (Lepidoptera: Tortricidae)

Field studies of male Oriental fruit moth,Grapholitha molesta (Busck), behavior indicated that a mixture of cis-8-dodecenyl acetate (c8-12∶Ac) and ca. 7% trans-8-dodecenyl acetate (t8-12∶Ac) was requisite for upwind anemotaxis. The simultaneous emission of dodecyl alcohol (12∶OH) and the attractant blend of c8-12∶Ac containing ca. 7% t8-12∶Ac elicited a behavioral repertoire including close-range orientation, landing near the chemical source, wing fanning, and extrusion of the males' abdominal hairpencils in precopulatory display. The effect of 12∶OH in increasing trap catches was, therefore, not due to its effect on upwind anemotaxis, but rather to its importance in eliciting landing and other close-range precopulatory behavior. Interestingly, cis-8-dodecen-1-ol in extremely low ratios to the attractants (1∶333) appeared to duplicate the activity of 12∶OH used in ratios of 3∶1 to the attractants. Laboratory observations of mating sequences revealed that male hairpencil eversion always preceded copulation. The evidence supports a male response sequence based on specific component combinations and concentrations eliciting successive behavioral steps rather than a response hierarchy dependent on increases in concentration of a single chemical or blend. Additionally, the closeness of the males' approach to c8-12:Ac containing ca. 7% t8-12:Ac was optimal at a discrete emission rate, and male responses were diminished within 30–60 sec after the males' arrival at the attractant source.     

碳酸钠溶液吸收处理硫化氢试验研究

研究了碳酸钠(Na2CO3)溶液吸收处理硫化氢(H2S)气体的效果。常温(20℃)常压下,当Na2CO3溶液质量浓度为10 g/L、H2S空间速度和初始质量浓度分别为5 L/(L.m in)和200 mg/m3时,可以得到以下结论:碳酸钠溶液吸收硫化氢的穿透时间是570 m in;在穿透时间570 m in内吸收效率维持在80%以上;吸收液pH值维持在9~12之间;吸收液pH=9.5时,吸收效率可以维持在80%以上。     

Olfactory basis of cannibalism in grasshoppers (Orthoptera: Acrididae): III. Use of attractants on carbaryl wheat bran bait

Two known necrogenic attractants, linoleic acid (18:2) and linolenic acid (18:3), were added to carbaryl bran bait to enhance control of rangeland grasshoppers in southeastern Wyoming. The primary goal was to increase control of species of Gomphocerinae, which normally do not consume bran bait. Each attractant was applied at 1, 5, and 10 grasshopper equivalents (GE) (e.g., a 1-GE treatment had the amount of fatty acid per unit weight of wheat bran that would be found in one grasshopper). Controls included carbaryl bran with no attractant and no treatment. Bran was applied at a rate of 1 kg/ha to 1-ha blocks on June 6, 1992, with four replicates per treatment and control. Plots were sampled for grasshoppers and nontarget organisms one day prior to and one, two, and three days after treatment. The addition of linoleic acid (10 GE) resulted in significantly lower total grasshopper densities than carbaryl bran alone. None of the attractants significantly improved control of all Gomphocerinae due to inconsistent effects among species. Relative to carbaryl bait alone, all doses of both fatty acids significantly improved control ofAmphitornus coloradus (Thomas). However, the attractants did not change the level of control ofCordillacris occipitalis orAulocara elliotti, and linolenic acid (5 GE) and linoleic acid (1 GE) resulted in significantly poorer control ofAgeneotettix deorum (Scudder) than carbaryl bait alone. Nontarget arthropods were largely unaffected by the attractants, except for the spiders, which were significantly reduced in all linolenic acid treatments.