Exotic leafmining sawflies (Hymenoptera: Tenthredinidae) on birch (Betula spp., Betulaceae) have become widely distributed in Canada since their introduction to eastern North America in the last century (Digweed et al. 1997). However, their distributions north of the 60th parallel are poorly known (Digweed et al. 2003). No birch leafmining sawflies were detected at Hay River and Louise Falls, Northwest Territories (NT), in 1993, but the ambermarked birch leafminer, Profenusa thomsoni (Konow), was reported from Yellowknife, NT, in 1994 (Digweed et al. 1997). Since that time, P. thomsoni populations have reached epidemic levels on urban birches in Yellowknife and Hay River, NT (unpublished data). While examining infested birches in Hay River in 2003, the authors also found the European alder leafminer, Fenusa dohrnii (Tischbein), attacking alder (Alnus spp., Betulaceae).

Pheromone trap catches and mating activity of sterile, mass-reared, diapaused and non-diapaused male codling moths, Cydia pomonella (L.) (Lepidoptera: Tortricidae), were compared with those of wild diapaused males using mark–release–recapture field experiments in springtime. Sterile moths were provided by the Okanagan–Kootenay Sterile Insect Release (SIR) Program mass-rearing facility, in Osoyoos, British Columbia, Canada. Nondiapause-reared (SIR-standard) and diapause-reared (SIR-diapaused) sterile males were recaptured in similar frequencies. Both types of sterile males were recaptured significantly less often than similarly released wild diapaused males, and ratios of recaptured sterile to wild males were similar with either sterile male. Ratios of sterile to wild males, using the combined catches of SIR-standard and SIR-diapaused males, were significantly lower when measured with traps baited with wild-females (21:1) than with traps baited with 10 μg pheromone (48:1). Both trapping ratios were markedly lower than the 80:1 ratio at which sterile and wild males were released. In mating studies, SIR-standard and SIR-diapaused males exhibited equivalent mating frequencies and both were recaptured in copula with tethered wild females significantly less often than released wild males. In the same mating studies, sterile mass-reared, diapaused males that had been chilled for 3 h at the Pacific Agri-Food Research Centre (PARC) before release (PARC-diapaused) were significantly more competitive than SIR-standard or SIR-diapaused males that averaged 24 h of chilling as part of normal SIR Program operations. PARC-diapaused males and released wild males mated with tethered females with equal frequency. We hypothesize that the length of time SIR males were chilled before being released may have caused SIR-diapaused males to be less mobile, and therefore less competitive with wild males in field mating assays, than were PARC-diapaused males. Based on these results, introduction of a diapause phase into the mass-rearing system used at the Osoyoos facility cannot currently be recommended as a means of improving trap-measured ratios of sterile to wild males, or increasing sterile × wild matings.

The species belonging to this interesting family have received very little attention from Entomologists generally, and considering the extent of the North American fauna, comparatively few species have been described. Of these almost nothing is known of their habits and development.

Pheromone lures for eastern and western blackheaded budworms, Acleris variana (Fernald) and A. gloverana (Walsingham), were synthesized and deployed in traps at locations with decreasing and increasing populations of western blackheaded budworms in British Columbia, Canada. Traps baited with these lures caught comparable numbers of moths at all sites tested in each year. The lures were sensitive to changes in density of budworm populations below observable damage levels, and numbers of moths in traps were strongly correlated with independent estimates of egg densities in the same year. The results confirm the qualitative similarity of the sex pheromones in eastern and western species of blackheaded budworm and demonstrate their utility as a tool for monitoring population trends, including increases in populations to damaging levels.

The results obtained in the experiments just described indicate that the discriminative ability of the female parasite operates to enable the parasite to distinguish between hosts which have been parasitized previously, not only by itself but by other members of the species, and perfectly health; hosts. If this were not the case, series in which the densities of the female parasite populations were high would have given results which were more nearly approximate to a random distribution of progeny among the available hosts. As we have seen, the tendency was for the parasite to avoid superparasitism under all conditions, i.e., to exercise a deliberate choice of hosts.

The bertha armyworm, Mamestra conjigurata Wlk., is a polyphagous climbing cutworm (Lepidoptera: Noctuidae) that attacks canola (Brassica napus L. and B. campestris L.) in the prairie provinces of Canada. Following the outbreaks of 1971–1974 (Turnock and Philip 1977), sampling methods to determine larval density in the field were developed by researchers in Manitoba, Saskatchewan, and Alberta. The methods were basically similar, using a 3-sided metal frame to outline each 0.5-m2 sample unit, with the long side of the frame (1 m) parallel to the rows of the crop. The differences were in the way in which the plants and soil surface were searched for larvae. In Manitoba, the plants within each sampling unit were shaken by hand, then the soil surface was examined for larvae and earthen lumps and plant debris were moved to expose hidden larvae. In Saskatchewan, the plants were shaken, then cut near the base and discarded before the ground surface and debris were searched. In Alberta, the plants were cut near the base, then shaken over a sheet, and the sheet and ground surface were examined for larvae.

A study was conducted to examine the relationship between development rate and constant temperatures (14, 21, 24, 27, 33, 36, 40, and 45°C) for the rangeland grasshoppers Melanoplus sanguinipes (F.) and Aulocara elliotti (Thomas). Non-linear regression was used to generate estimates of lower development thresholds. The chosen model provided for a concave-shaped development rate function at temperatures above the lower threshold and required fewer parameters than previous models. Although experimental results suggested that no precise estimates of upper development thresholds could be obtained, previous field studies indicate that preferred body temperatures may be lower than ambient temperatures and probably are related in part to the thermoregulatory abilities of the two species studied. Results will be of interest to insect ecologists and those studying grasshopper biology as well as researchers and pest managers interested in predicting grasshopper development.

When the polyphagous parasite Itoplectis conquisitor (Say) was reared on either of two hosts, Thymelicus lineola (Ochs.) or Galleria mellonella L., it showed no preference for the host from which it had emerged when exposed to equal numbers of the two hosts in the same type of ecological niche. No evidence for the existence of preimaginal conditioning in I. conquisitor was obtained.

Attacks by Scolytus ventralis on white fir were correlated both with periods of low precipitation and with medium to heavy infestations of true mistletoe. Trees were seldom attacked when the "running mean precipitation" was above 54 in. Attacks were significantly more frequent and were often a year or more earlier on trees with substantial amounts of mistletoe. Broods were seldom produced, however.Data suggest that heavy mistletoe infestation rendered trees more susceptible to beetle infestation, possibly by creating moisture stress in infected trees.

Palmistichus elaeisis Delvare and LaSalle, Tetrastichus howardi (Olliff), and Trichospilus diatraeae Cherian and Margabandhu (Hymenoptera: Eulophidae) are promising candidates for the control of sugarcane borer, Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae). The fungi Beauveria bassiana (Balsamo) Vuillemin (Cordycipitaceae) and Metarhizium anisopliae (Metchnikoff) Sorokin (Clavicipitaceae) also can be used to control sugarcane borers plus leafhoppers (Hemiptera: Cercopidae) in sugarcane. This observation motivated us to investigate whether entomopathogenic fungi can affect biological aspects of these parasitoids. Diatraea saccharalis pupae (24 hours in age) were exposed to parasitism by three females of each eulophid species for 72 hours and then placed in small tubes. A contact surface treated with 1 mL of fungal suspension was placed inside each tube with the parasitised pupae at concentrations of 1×109, 5×109, or 10×109 conidia mL−1 of M. anisopliae and B. bassiana. Exposure to fungi reduced emergence of adult P. elaeisis, but not of T. howardi and T. diatraeae. Life cycle duration, progeny, and sex ratio of P. elaeisis were not affected by exposure. Exposure was associated with decreased longevity for both sexes of T. howardi and in males of P. elaeisis, but not at levels expected to affect their performance as biocontrol agents. In general, the exposure of eulophid species developing in pupae of D. saccharalis exposed to entomopathogenic fungi, did not compromise the biological aspects of these parasitoids.

The present paper is an outgrowth of a collecting trip made by myself to the eastern arctic during the summer of 1935. The month of August was spent in the vicinity of Lake Harbour, Baffin Island, and brief stops were made at Port Burwell, Que., at Craig Harbour, Ellesmere Island, and at Pangnirtung and Clyde, Baffin Island. Results were satisfactory, considering the difficulties which the collector must experience in the region, and this success was due largely to indispensable aid received from Major D. L. McKeand of the Lands, Northwest Territories and Yukon Branch, Department of the Interior, and from Mr. James Bell and Mr. Nelson Adams of the Hudson's Bay Company, Lake Harbour.

Insects caused serious damage to cones and seeds of white spruce during one of the five years of this study. A new seed and cone insect, Pegohylemyia sp., was recorded for the first time from Alaska. This insect destroyed an average of 50% of the seeds per cone.

Adults of Trisetacus chamaecypari n. sp., and female adults of T. thujivagrans n. sp. are described, and species of Trisetacus associated with Cupressaceae and Taxodiaceae are discussed and keyed. An original diagnosis of the genus Trisetacus is included.

Sterilization of male and female Ips confusus (Coleoptera: Scolytidae) exposed to gamma radiation (Co60) as newly emerged adults was almost complete at levels exceeding 7500 r and 10,000 r, respectively. Mating behavior of males as expressed by sperm transfer was unaffected by dosages up to 60,000 r. The capacity of beetles of either sex to establish galleries was not affected significantly below this dosage, but female gallery pattern was altered above 15,000 r. Longevity was reduced at levels greater than 5000 r. LD50 for males occurred at 11.5 days at 7500 r and 29 days in the controls. Mortality of progeny resulting from males irradiated at substerilization levels was higher than in the controls. The dosage to achieve significant population reduction with minimum effect on longevity and other biological activity is estimated to lie between 6000 and 7500 r.

These studies indicate that this sterilization technique may have promise in the control of bark beetles. The necessity for rearing large numbers on artificial media could be circumvented by mass trapping utilizing their natural sex attractant and by mass rearing in cut host material in the laboratory.

Microscopic examinations revealed that free-floating hard black bodies in larvae, pupae and adults of the Swaine jack-pine sawfly, Neodiprion swainei Midd., often contained polyhedra. A simple and rapid method for detecting the presence of the virus infection before gross symptoms appear is described.

Melanolophia imitata (Walker) has been colloquially referred to as the green-striped forest looper, in reference to its appearance and habitat. The spring-flying adults and the consistently large numbers of larvae attract considerable attention annually. Although the moths evince little migratory movement, their comparatively large size and pale colour, in association with their quantity, combine to create the basis for occasional alarming reports of forest insects. It is not infrequent to hear of clouds of moths scattering about a forest traveller and viewed throughout the woods. Ordinarily the adults fly during late evening, and are less attracted to light than many moths.

Entomology in Canada began about the middle of the nineteenth century with a small but able group of hobbyists. They became active shortly before confederation in what was then the Province of Canada, a temporary union ofthe present provinces of Ontario and Quebec. Today, a century later, the science is firmly founded throughout the coilntry with over 400 professional entomologists, more than 50 well-equipped research centres, 16 institutions giving formal instruction, and eight profesional societies. Entomological advisory services are estahlished in several provinces and federal legislation protects the public against the spread of nosious insects and the fraudulent or dangerous sale of materials for their control.

The sampling of bark beetles and their natural enemies requires that bark be removed for examination of broods contained in the phloem. Counts of populations on bark samples are used to evaluate infestations for purposes of control and for studying population dynamics in the field. Bark samples have been cut from western conifers by chopping, sawing, or a combination of these operations. However, both these methods have disadvantages. Chopping produces ragged samples of varying size, and a saw tends to catch in the bark when cutting boundaries parallel to the trunk. Also, with either chopping or sawins, sample boundaries must be measured and marked as a guide during the cutting.

The species of Aphidini living on Senecio L. in South America are reviewed. Pehuenchaphisgen. nov. is described; it is an Aphidina genus characterized mainly by the siphunculi on abdominal segment VI when present and by its radicicolous way of life. The type species of the genus Pehuenchaphis agilissimasp. nov. is described and the new combination Pehuenchaphis americana for Sene ciobium americana Mier Durante and Ortego is established. Aphis senecionicoides E.E. Blanchard is redescribed and its neotype is established. Aphis papillosasp. nov. with very large marginal papillae and Aphis malalhuinasp. nov. with short siphunculi are described and differentiated from the previously known Aphis intrusa Ortego and A. senecionicoides. A key for the apterous viviparous females of these seven species and Andinaphis paradoxa Mier Durante et al. is given.

The pheromone specificity of female Choristoneura occcidentalis Freeman and C. retiniana (Walsingham) from several locales, laboratory colonies, and interspecific matings was determined by observing the numbers and wing maculations of males attracted at several sites in southern Oregon. Pheromone specificity of females reared from field-collected brown (typical of C. occidentalis) and green (typical of C. retiniana) larval morphs differed considerably but differed little among sites of origin. Field-collected females attracted more males than conspecific individuals from laboratory colonies. F1 and F2 interspecific hybrids most closely resembled C. occidentalis in the numbers and types of males attracted. As a group, progeny of backcrosses to C. retiniana appeared intermediate between pure lines of the species in their pheromone specificity. Females reared from intermediate-colored field-collected larvae varied considerably in attractiveness. Most attracted groups of males similar to those attracted to female C. retiniana, but others attracted males most similar to those attracted to female progeny of C. retiniana hybrid backcrosses. These findings support the conclusion that hybrid matings occur between these species at a low frequency in nature.