Pine oil (Norpine-65, Northwest Petrochemicals) was assessed as an oviposition deterrent for gravid female onion maggots, Delia antiqua (Meigen), in two types of laboratory experiments. When given a choice for 24 h between a control onion half treated with hexane and an onion half treated with pine oil in hexane, the females oviposited preferentially on or around the control onion half. In a no-choice experiment the females laid over three times as many eggs on or around solvent control onions as on or around onions treated with 1.0% pine oil. The DC50 (deterrent concentration50) was calculated to be 0.09%. The results suggest that pine oil (or its constituents) may have potential as an oviposition deterrent under field conditions.

A key to the species of Hymenoptera that parasitize insects feeding on sunflower seed heads is presented. The data base for this work is from rearings done in mid-western Canada but the key should be reliable throughout North America. A discussion of each parasitoid, giving host records, distribution, references, and a morphological diagnosis, is presented. Finally, a list of all of the species of parasitic Hymenoptera associated with sunflower in North America is given including important references.

The Donacia subtilis species-group, comprising D. subtilis Kunze, D. fulgens LeConte, D. confluenta Say, and D. tuberculifrons Schaeffer, is newly defined. A key to species, and genitalic figures of males for the species are given. Types are designated for all names where necessary. Donacia cuprea Kirby, 1837 (lectotype female, BMNH, designated herein), the oldest name available for D. quadricollis, auctorum, is revalidated. Donacia quadricollis Say, 1827 (neotype male, MCZ, designated herein) is newly placed as junior subjective synonym of D. subtilis Kunze, 1818. Donacia confluenta Say, 1827 (neotype male, MCZ, designated herein) is removed from synonymy of D. subtilis Kunze on the basis of differences in male genitalic structure. Donacia magistrigata Mead, 1938, is transferred from junior subjective synonymy of D. fulgens LeConte, 1851 (lectotype male, MCZ, designated herein) to junior subjective synonymy of D. subtilis Kunze, on the basis of similarity of male genitalic structure. The collection of Ahrens is lost, therefore a neotype for D. aenea Ahrens, 1810, not Hoppe, 1795, is designated (CNC, male). Donacia aerea Lacordaire, 1845 (lectotype, male, BMNH, designated herein) remains as junior subjective synonym of D. subtilis Kunze.

By injecting fenitrothion into fluid in leaves of pitcher plants, Sarracenia purpurea L., it was determined that the mosquito, Wyeomyia smithii (Coquillett), and the midge, Metriocnemus knabi (Coquillett), are under some risk from fenitrothion forest sprays at the rate of 210 g AI/ha. Wyeomyia smithii is slightly more susceptible than is M. knabi. Other leaf inhabitants, mites and rotifers, were not affected by initial concentrations of fenitrothion in the fluid (up to 9.6 μg/L) that did affect the mosquito and the midge.

A study was conducted to examine the springtime hatching characteristics of Melanoplus sanguinipes (F.) and Aulocara elliotti (Thomas) eggs on rangeland. Laboratory experiments showed that eggs of M. sanguinipes required fewer accumulated degree days (DD) to complete post-diapause development than those of A. elliotti at a constant temperature of 23.3°C. Springtime field observations revealed that A. elliotti nymphs emerged prior to or concurrent with M. sanguinipes. Additionally, results suggest that A. elliotti nymphs emerge over a shorter interval than M. sanguinipes. Much of the variation in springtime emergence could be attributed to species-specific oviposition sites, pod depth, and pod orientation that resulted in A. elliotti eggs accumulating heat more rapidly than M. sanguinipes eggs. Results help explain some of the variation found in egg hatching of these two grasshopper species on rangeland.

The faunas of Newfoundland and Cape Breton include 217 leafhopper species, of which 24 are introduced and 65 are native, common to both islands. Newfoundland has 116 species, of which 86 are new provincial records and 2 are new nearctic records of introduced European species. Cape Breton has 172 species, of which 109 are new records for Nova Scotia. A species previously known as far north as Virginia was found in Cape Breton, 2 New England species were found as far north as Newfoundland, 2 high boreal species were found as far south as Cape Breton, and 42 species previously known from west of Maine were found as far east as Cape Breton. One new subspecies and 14 new species are described: Cosmotettix unica, Oncopsis minor terranovae and Typhlocyba (Edwardsiana) unicorn from Newfoundland, Colladonus balius, Cribrus micmac, and Typhlocyba (Zonocyba) hollandi from Cape Breton, Oncopsis speciosa from both islands, Erythroneura maritima and M. inundatus from the Gulf of St. Lawrence region, Limotettix (Ophiolix) schedia, Latalus (Jassargus) remotus and Macrosteles galeae from eastern bogs, and Empoasca volsella, E. zanclus and Kyboasca papyriferae from Cape Breton westward across Canada. Three new synonyms are created: Amphigonalia Young, 1977 = Neokolla Melichar, 1926, Scaphytopius sarissus Beirne, 1952 = S. cinnamoneus (Osborn, 1915), and Typhlocyba frigida Hamilton, 1983 = T. tersa Edwards, 1914. Three genera are reduced to subgenera: Jassargus Zachvatkin, 1953 in Latalus DeLong & Sleesman, 1929, Lemellus Oman, 1949 in Sorhoanus Ribaut, 1946, and Scleroracus Van Duzee, 1894 in Limotettix Sahlberg, 1871. New World species formerly placed in Agallia Curtis are transferred to Agalliota Oman. Oncopsis prairiana Hamilton, 1983 and its subspecies are made subspecies of O. minor (Fitch 1851). The composition of the faunas of the two islands is compared with those of adjacent areas of the mainland, and evidence is found for an offshore glacial refugium.

Four 10-ha plots located in Kamloops Forest District, British Columbia, containing Douglas-fir trees infested with Douglas-fir tussock moth were aerially sprayed with nuclear polyhedrosis virus (Virtuss) in 1982 when most larvae were in the first instar. A dosage of 2.5 × 1011 polyhedral inclusion bodies (PIB) per hectare was applied in an emulsifiable oil tank mix to one plot and the same dosage in an aqueous tank mix containing molasses was applied to a second plot. The remaining two plots were treated with dosages of 8.3 × 1010 and 1.6 × 1010 PIB per hectare, respectively, in the oil mix. The treatments were applied with a fixed-wing aircraft fitted with boom and nozzle equipment and calibrated to deliver 9.4 L/ha. A further four plots were selected as checks.

Population reduction at 6 weeks post-spray (calculated using a modified Abbott’s formula) was 65% in the plot receiving the lowest dosage and from 87 to 95% in the remaining three plots. Incidence of virus infection, determined microscopically, peaked at 5–6 weeks post-spray with 85–100% of the larvae scored as positive. Levels of naturally occurring virus remained low in the check plots. Adult emergence from the pupae collected in the treated plots ranged from 4 to 19% and from 28 to 43% in the check plots. Reduction in egg-mass density attributed to the treatments was 97% in one plot, 99% in two others, and not determined for the fourth.

A virus dosage of 8.3 × 1010 PIB per hectare, which is one-third of the previously recommended dosage, is adequate, and either tank mix is acceptable.

Following aerial application of a Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), nuclear polyhedrosis virus (NPV) product called Virtuss on four plots in 1982, observations were made to determine the impact of these treatments in 1983 and 1984. Treated plots as well as buffer zones between and adjoining the treated plots, and three of the four check plots established in 1982, were monitored. The NPV appeared to have spread from the treated plots to adjoining areas in 1982, effectively reducing the Douglas-fir tussock moth population. This observation suggests that a strategy of spraying alternate swaths of Douglas-fir tussock moth infested stands with this viral insecticide may effectively initiate an epizootic that would control the population at a reduced cost.

A naturally occurring NPV epizootic decimated the Douglas-fir tussock moth population in the three check plots in 1983, but severe tree mortality occurred in two of these plots with 60 and 62% of sample trees dead in 1984. Light tree mortality was noted in 1984 in two of the four treated plots with 4 and 7% of sample trees killed. It is concluded that the virus treatments in 1982 were successful in preventing tree mortality.

Relationships between temperature and development rates of eggs, overwintered second-instar larvae, and all larval stages of Choristoneura fumiferana (Clem.) fed on artificial diet were determined. Egg development was observed at eight constant temperatures between 7 and 32°C. It was fastest at 30°C, and showed relatively little variability. The rate of emergence of overwintered second-instar larvae was observed at 10 constant temperatures between 4 and 33°C. Maximum development rates occurred at 30°C. Variability in emergence rates was large, but unimodal. Development rates of the second to sixth larval instars were measured at 10 constant temperatures between 7 and 36°C, and maximum rates were observed, again, at 30°C. Variability in the development rates of the larvae was large, with no correlations between the development rates of the various larval instars. The results of computer simulations of the insect’s seasonal history are presented and discussed.

Parasitism of Colorado potato beetle, Leptirwtarsa decemlineata (Say), by the tachinid fly Myiopharus doryphorae (Riley) was monitored over four summers. Beetle larvae were collected from potato and a wild host species, Solanum sarrachoides Sendt., and allowed to complete development in the laboratory. Parasitism rates were high, averaging 67, 58, and 45% over the 4 years, in June, July, and August, respectively. Categorical analyses indicated that parasitism rates were dependent upon year, month, and host plant species of the beetle. During 1983–1985, rates were highest in June, and decreased over the summer; results for 1986 were somewhat atypical, with parasitism rates being low in June and increasing somewhat in August. Host plant effects on parasitism varied with year. During 1983–1984, rates were higher for beetles collected from potato than beetles collected from S. sarrachoides; this tendency was reversed in 1985.

Wild bee pollinators were collected in tree-fruit orchards and uncultivated habitats in the Okanagan Valley. Higher abundance and diversity of wild bee pollinators were found at uncultivated sites than on tree-fruit crops. Wild bees were not abundant enough in orchard habitats to provide adequate tree-fruit pollination. Variable flower visitation patterns by polylectic bees in orchard and uncultivated habitats make it difficult to predict floral visitation patterns. Therefore, orchardists cannot rely on a substantial and predictable contribution to pollination of fruit crops by wild bee species. Research into the use of wild bees as managed pollinators for tree-fruit crops in the Okanagan Valley may have potential. Future studies should consider three wild bee species collected in Okanagan Valley orchards, Bombus terricola occidentalis Greene, Bombus bifarius nearcticus Handlirsch, and Osmia lignaria propinqua Cresson, for pollination management.

The construction of a simulated-ear-insect-trap (SEIT) for ear-feeding black flies is described. The SEIT, which consists of a styrofoam container with dry ice and a mock sticky ear mounted on a tripod, was developed to capture Simulium jenningsi Malloch and S. vittatum Zett., both widespread pests of livestock. SEIT units set on horse farms within 5 km north of the Potomac River in south-central Maryland, USA (n = 36 samples of 30 min each), consistently captured S. jenningsi and S. vittatum ( and 7.1 per sample, respectively), whereas units set simultaneously on farms > 5 km north of the river (n = 99 samples of 30 min each) captured progressively fewer individuals of both species.

Methods of separating Pissodes strobi (Peck) from its insect associates in leaders of Picea sitchensis (Bong.) Carr. would enable the associates to be returned to the field when infested leaders are routinely clipped to remove P. strobi. We recently demonstrated a method based on the relative lack of cold-hardiness of P. strobi (Hulme et al. 1986). Another method suggested many years ago (e.g. Taylor 1929) is to exploit the different ability of adult insects to crawl through a screen. To our knowledge the efficacy of such a separation has never been demonstrated. We report here an investigation into the ability of these adult insects to crawl through screens having openings of various sizes, with the objective of establishing how completely these insect associates could be separated from P. strobi