The oribatid mite genus Ametroproctus, soil and litter inhabitants in the desert, alpine, and montane regions of western North America, is discussed. Two subgenera are recognized, Ametroproctus s. str. and Coropoculia. Their respective type-species, A. oresbios Higgins and Woolley and C. reticulata Aoki and Fujikawa, are redescribed, and newly discovered immatures of both species are described. Four new species are proposed, A. (Ametroproctus) tuberculosus, A. (A.) aridus, A. (Coropoculia) beringianus, and A. (C.) canningsi. A new generic diagnosis is given, as well as a key to subgenera and species known from North America.

The dosage of carbofuran as a bait required to reduce third-instar grasshopper populations to non-economic levels (5–10 grasshoppers per square metre in short mixed grass hay pasture) was considerably lower than the recommended rate for spray application. The results from 2 years’ field trials showed that 35.0 g active ingredient per hectare as a bait would reduce grasshopper populations by about 70%, 3 days after application.

The abundances of eight species of cutworm and armyworm moths were monitored with sex-attractant traps at 81 locations in a 13 000-km2 area of southern Alberta from 1978 to 1983. The life history and economic status of each species is summarized and the monitoring methodology is described. The attractants for redbacked cutworm (Euxoa ochrogaster), darksided cutworm (Euxoa messoria), pale western cutworm (Agrotis orthogonia), and army cutworm (Euxoa auxiliaris) were highly specific and > 99% of the moths caught were of the target species. Specificity of the attractants for clover cutworm (Discestra trifolii) and Leucania commoides was also high, averaging 98.3 and 96.6%, respectively, over 6 years. The attractants for variegated cutworm (Peridroma soucia) and bertha armyworm (Mamestra configurata) were less specific but the proportion of target species exceeded 80% in those years when either species was relatively abundant. For those species that were monitored over a wide range of population levels, the apparent specificity of the attractant varied directly with the number of target species moths caught. The use of efficient attractants in combination with high-capacity nonsaturating traps is clearly of advantage in enhancing specificity.

Sex-attractant traps were used to monitor the relative abundances of eight species of cutworm and army worm moths at 81 locations in a 13 000-km2 (5000-mi2) area of southern Alberta from 1978 to 1983. Clover cutworm (Discestra trifolii (Hufn.)), variegated cutworm (Peridroma saucia (Hbn.)), bertha armyworm (Mamestra configurata Wlk.), and Leucania commoides Gn. were monitored during spring and early summer, and redbacked cutworm (Euxoa ochrogaster (Gn.)), darksided cutworm (Euxoa messoria (Harr.)), pale western cutworm (Agrotis orthogonia Morr.), and army cutworm (Euxoa auxiliaris (Grt.)) during late summer and fall.

The ranking of moth catches among locations within years was highly consistent, indicating that the spatial pattern of abundance within the survey area remained stable during each flight period. The corollary is that differences in population levels among locations were being consistently detected. Most of the species also exhibited a considerable degree of consistency of pattern of abundance between consecutive years and to some extent over all years.

Estimates of the variability associated with individual traps, between duplicate traps, and among locations were obtained for each species. The within-location variability was always much less than the among-location variability, indicating that a meaningful measure of the relative population level at each location was being obtained. When abundance levels approached economic thresholds the likelihood of moth catches in duplicate traps being within 20% of the mean catch for a location was usually greater than 80%. Year-to-year differences in mean trap catches were frequently significant at the 95% confidence level and the monitoring system could detect relatively small changes in population level between years. Season cumulative trap catches are a composite measure of abundance and the mate-searching activity of males. Weather conditions that restrict male activity are also likely to reduce oviposition by females. Cumulative trap catches may therefore be closely correlated with realized fecundity.

Grasshopper assemblages inhabiting eight pastures of shortgrass prairie rangeland in northeast Colorado were studied for 4–6 years during a general increase and decrease in grasshopper abundance. Average densities increased 10-fold during a 3- to 4-year increase phase, with individual species and populations in separate pastures exhibiting greater or lesser changes. Asynchrony in grasshopper population characteristics was noted. The co-dominant species, Opeia obscura (Thomas) and Melanoplus gladstoni Scudder, exhibited similar trends in density, but M. gladstoni dominance, expressed as its proportion of the population, declined steadily relative to O. obscura. Subdominant species similarly were asynchronous. Species richness did not change during this cycle. Grasshopper densities and assemblage structure were not affected by rangeland management practices of fertilizer (nitrogen) and herbicide (atrazine) application.

Three sequential-sampling plans were developed for adult Diabrotica barberi Smith and Lawrence and D. virgifera virgifera LeConte in field corn in southern Ontario. The distribution of both species was well approximated by the negative binomial distribution and obeyed Taylor’s power law. Two plans, following the methods of Kuno (1969) and Green (1970), estimated populations with predetermined precision. The third plan, based on Wald’s (1947) sequential probability ratio test, categorized populations relative to an economic threshold. Different sequential-sampling plans were constructed for 1st-year fields and for all other fields because the parameter k, measuring the extent of aggregation of the beetles, differed between these two classes of fields. Decision equations for Wald’s plan in 1st-year fields were: D1 = 0.98n − 17.75 and D2 = 0.98n + 13.82. Decision equations for 2nd-year or older fields were: D1 = 0.99n − 13.42 and D2 = 0.99n + 10.45. The use of Wald’s plan reduced the required sample size by 55% in 1st-year fields, and by 48% in all other fields. The savings associated with the other sequential-sampling plans were not significant.

Western spruce budworm, Choristoneura occidentalis Freeman, adult males were observed in a wind tunnel for their response to synthetic sex pheromone and subsequently examined to determine their degree of infection with a microsporidian parasite, Nosema sp. A subsample of C. occidentalis was randomly selected and electroantennograms (EAG) of individual moths were measured for response to pheromone. The Nosema infection level ranged from 0 to 21.8 × 106 spores per milligram and was significantly negatively correlated with the proportion of males wing-fanning, taking off, and flying upwind to contact the pheromone source. The level of Nosema infection and the amplitude of the antennal response (EAG) to pheromone were not significantly related. These results suggest that Nosema affects the response of C. occidentalis males to pheromone in some way other than directly reducing the sensitivity of the antennae. We hypothesize that sublethal infections of Nosema sp. may reduce mating success of the western spruce budworm in field populations.

Fumigants that are liquid formulations at room temperature have been widely used to kill insects in stored products, containers, and soil. Carbon bisulfide was one of the first fumigants used on a large scale as early as 1869 and is still the main fumigant used in some parts of the world (Bond 1984). Carbon bisulfide is highly flammable (Fleming and Baker 1935) and is usually formulated with carbon tetrachloride to aid distribution of fumigants in grain masses (Berck 1958) and to reduce the fire hazard. Although carbon tetrachloride is of low toxicity to insects it causes extensive liver damage in humans (Rouiller 1964). Liquid fumigants were widely used to disinfest stored grain in the USA until recently (White et al. 1985), and are still used in many other parts of the world (FA0 1985).

Enhancement of virulence in entomogenous fungi has been a particularly neglected area of research (Roberts and Yendol 1971). It is generally believed that virulence increases following successive passage through a host and decreases following repeated subculturing on artificial media (see Aizawa 1971; Roberts and Yendol 1971). Using single-spore isolates (clones) of Beauveria bassiana (Bals.) Vuill., SamšiňSáková and Kálalová (1983) demonstrated spontaneous mutants with increased virulence. Enhancement of virulence using parasitic selection pressures has been accomplished by passage of fungal strains through a host (Daoust and Roberts 1982; references in Ignoffo et al. 1982). Such changes are thought to be due to gradual selection of genotypes.

Sperm transfer in the aphidophagous ladybird beetle, Harmonia axyridis Pallas, is by a spermatophore (unpublished data). Although the utilization of spermatophores in insects has been considered to be a more primitive method of insemination than direct sperm transfer, males of many orders produce spermatophores (Chapman 1969; Gerber 1970; Leopold 1976). The remains of the spermatophore, after the sperm has migrated to the spermatheca, is ejected by the female in some species and dissolved within the female genital tract in others (Chapman 1969; Leopold 1976). In Coccinellidae, Fisher (1959) reported on spermatophore formation of Chilocorus spp. and indicated that the female ejected the empty spermatophore 18–24 h after copulation. In this paper evidence is presented that H. uxyridis females not only eject the empty spermatophore but also feed on it.