Two, 1400-ha blocks of rangeland in western South Dakota were treated aerially with malathion liquid spray or carbaryl – bran bait in early July 1986 to determine the immediate and 2nd-year impact of treatments on grasshopper populations. Total grasshopper populations were reduced by 92 and 47% in the malathion and carbaryl – bran bait treatment plots, respectively, within 48 h after treatment and remained at a low level throughout the summer. Populations did not change in the control plots. Populations of the two most abundant species, Ageneotettix deorum (Scudder) and Melanoplus sanguinipes (F.), declined by 65 and 87%, respectively, in the carbaryl – bran bait plots but populations of bran "rejectors" (predominantly Trachyrhachys kiowa [Thomas]) did not change.

Densities of the bran "acceptors" (Melanoplus spp., Phoetaliotes nebrascensis [Thomas], and A. deorum), as a group, did not change significantly in the control plots between the pre-treatment and July 1987 sampling dates. Densities within both sets of treatment plots were significantly lower in the 2nd year of the study than on the pre-treatment sampling date. Although 2nd-year populations of bran acceptors, as a group, did not increase to pre-treatment levels in the treated plots, populations of M. sanguinipes did increase to pre-treatment levels in both sets of treatment plots. Populations of bran rejectors generally remained low in treatment and control plots.

Analysis of covariance of the densities of 2nd-year populations of total grasshoppers and bran rejectors indicated that treatment had no significant effect on populations of these grasshoppers, but the covariable, pre-treatment density, was significantly correlated with 2nd-year densities. Densities of 2nd-year populations of bran acceptors were also significantly correlated with pre-treatment densities.

It was concluded that both the insecticidal spray and bait were effective in controlling most economically important species of rangeland grasshoppers. Although both treatments may have suppressed populations of bran acceptors, as a group, in the 2nd year of the study, neither suppressed populations of M. sanguinipes which increased to pre-treatment levels regardless of treatment. The effect of treatments on 2nd-year populations of bran rejectors could not be determined because populations of this group also declined in control plots.

Laboratory tests with selected carbamate, organophosphorus, and pyrethroid insecticides demonstrated that the pyrethroid permethrin has the best potential for controlling newly hatched larvae of Zeiraphera canadensis Mut. and Free. Permethrin possessed high crawling contact toxicity (toxicity of insecticide deposits on foliage when contacted by crawling larvae) and direct contact toxicity to first-instar larvae and exhibited long residual effectiveness on potted, white spruce trees. Chlorpyrifos, fenitrothion, mexacarbate, and methomyl had high crawling contact toxicity but short residual activity. Azinphos-methyl appeared to possess long residual effectiveness but relatively low crawling contact toxicity. Aminocarb and thiodicarb exhibited short residual effectiveness and relatively low toxicity. In field trials, an aerial application of permethrin (70 g/ha) at egg hatch resulted in an 81% population reduction and limited the destruction of tree leaders to 9%. Leader destruction was greater than 19% after treatments of permethrin at 35 g AI/ha or aminocarb at 180 g AI/ha or aminocarb twice at 90 g AI/ha. Leader destruction in an untreated plantation was 51%.

Morphometric analysis of 16 body measurements of migratory and solitary Melanoplus sanguinipes (F.) and M. spretus (Walsh) was used to determine if M. spretus was, in fact, the migratory phase of M. sanguinipes. Migratory M. sanguinipes was found to be more similar to its own solitary phase than to M. spretus. Melanoplus spretus resembled migratory M. sanguinipes, but in 14 comparisons M. spretus differed significantly from both solitary and migratory M. sanguinipes. Despite the potential for environmental variation obscuring differences in morphology, the divergent morphometric characters of M. spretus and the phases of M. sanguinipes appear to justify the status of M. spretus as a true species.

Two new species of Brachypauropodidae are described, Aletopauropus tanakai and Deltopauropus reticulatus. They represent the first records of the family from Japan.

The lodgepole terminal weevil, Pissodes terminalis Hopping (Coleoptera: Curculionidae), is widely distributed in western North America on three races of lodgepole pine (Pinus contorta Dougl.), as well as jack pine (P. banksiana Lamb.), Bishop pine (P. muricata D. Don.), and Monterey pine (P. radiata D. Don.).

Three types of life cycle, one with three subtypes, are identified. In the univoltine type 1 cycle, adults emerge from attacked leaders in the fall, overwinter probably in the ground, and re-emerge in the spring to lay eggs in elongating leaders. Larval and pupal development is completed by early fall. The univoltine type 2 life cycle is similar, except that overwintering takes place in leaders; fourth-instar larvae overwinter in type 2A, pupae in type 2B, and adults in type 2C. The type 3 life cycle takes 2 years to complete, with the first winter being passed as a third-instar larva in the leader and the second as an adult, probably in the ground. The type 1 life cycle is most common at altitudes < 2000 m and the type 3 life cycle at altitudes over ca. 2500 m; all types may be found at altitudes of 2000–2500 m.

The effectiveness of seven insect juvenile hormone analogs (JHAs) in disrupting metamorphosis of the eastern spruce budworm, Choristoneura fumiferana Clemens, was determined by applying the compounds topically to early sixth-instar larvae and monitoring subsequent development. Fenoxycarb showed promising control potential, with an LC50 of 0.26 μg per insect. Relative lethal effectiveness, based on LC50 values, was Fenoxycarb > ZR9892 > ZR8487 > S-71639 > methoprene > ZR9582 > ZR10151. Some of the JHAs tested may be useful in an integrated spruce budworm control program.

Collections of larvae over 1 year in the River Clinton in the White Mountains of southern Québec indicated that Palaeodipteron walkeri Ide is bivoltine and that there are five larval instars. In April, larvae were in their fourth and fifth instars. Adults emerging in May and June gave rise to a summer generation in which most individuals emerged in August and September. The offspring of these adults, together with stragglers from the summer generation, formed an overwintering generation. Overwintering was completed in the larval stage, mainly the third and fourth instars. There was some growth in winter and development increased in the spring. Our data were compared with previously published observations; although no discrepancy occurred, our interpretation was different. Previous schemes proposed for the life cycle in this species were based on few specimens and lacked winter observations.

The balsam twig aphid, Mindarus abietinus Koch, infested nearly all trees in a range-wide provenance plantation of balsam fir, Abies balsamea (L.) Mill., in Michigan. Infestation levels were highest on eastern and lowest on western seed sources of fir. Large populations of the aphid were correlated with low survival and reduced developmental rates of the spruce budworm, Choristoneura fumiferana (Clemens). We propose that chronic, high susceptibility of trees to aphids could reduce concomitant susceptibility to budworm through direct (competition) and indirect (host and community-level) effects.

Economic injury levels and economic thresholds for nymphs of Lygocoris communis (Knight) were defined in apple orchards, using the beating technique. These were determined with 1987 apple market value and chemical control costs. Economic thresholds were established, assuming a 24-h period required for control implementation. Highly significant relationships were found between the damage at harvest and the captures of young nymphs of L. communis. The economic injury levels ranged from 0.4 to 5.8 young nymphs per sample unit depending on the sample unit and insecticide used.

The immature stages of Athrycia cinerea (Coq.) including the egg, three larval instars, and the puparium are described and illustrated. The male and female reproductive systems are also illustrated and described and notes on oogenesis are provided.

Woolly-bear caterpillars of Grammia blakei (Grt.) are sometimes abundant in early spring on overgrazed native range pastures in southern Alberta and southwestern Saskatchewan, occasionally reaching population densities exceeding 50 per square metre (Byers 1988). Grammia blakei has a wide distribution in the Great Plains and Intermountain regions of western North America. Although the brownish-black caterpillars are quite often abundant, the moths (Fig. l), which are not attracted to food baits or light traps, have been rarely collected and few field-caught specimens are present in collections (D.C. Ferguson, U.S. National Museum, Washington, DC; J.D. Lafontaine, Biosystematics Research Centre, Ottawa, personal communication).

The joint action of permethrin and Bacillus thuringiensis var. kurstaki Berliner (B.t.), Autographa californica (Speyer) nuclear polyhedrosis virus (ACNPV), or Artogeia (= Pieris) rapae (L.) granulosis virus (ARGV) fed as mixtures to larvae of Trichoplusia ni (Hübner) or A. rapae in laboratory bioassys differed with the host insect, the components, and the concentrations of the components. Permethrin interfered with the activity of ACNPV and ARGV in most of the mixtures, particularly at low concentrations of the latter virus but mortality by mixtures of mid-range (approximately LC50 if fed alone) concentrations of permethrin and of ACNPV exceeded the mortality expected by the components acting independently. Concentrations of permethrin in the middle of the dosage range enhanced the effect of B.t. against T. ni resulting in mortality that exceeded the expected mortality but mortality of A. rapae larvae fed most permethrin–B.t. mixtures was less than expected.

George Holland's superb monograph on the fleas of Canada, Alaska and Greenland was published as Memoir of the Entomological Society of Canada No. 130 on 11 March 1985 (not in 1984 as indicated on the spine of the monograph). This work was immediately adopted by those of us working with the northern North American flea fauna. Because of George's lengthy illness, he was unable to correct galley proofs to his usual high standards. Unfortunately, George Holland passed away later in 1985, before he was able to address corrections to the monograph. What follows is a compilation of the errors that we have detected since the monograph was published. We have made no attempt to reinterpret Holland's taxonomic or biogeographical concepts, nor in any way change the meaning of the text. We have included additional references that pertain to the relevant geographic areas, either where Holland did not refer to them in the text, or which appeared subsequent to completion of the manuscript, up to and including year of publication (1985). The authors thank Agriculture Canada for financial support in the publication of this manuscript.

Nematode parasites of bark beetles are taxonomically diverse, and may, in some cases, cause serious pathological and behavioural changes in their hosts (Kaya 1984). Their potential as biological control agents has long been recognized, but to date there is a shortage of elementary information on host-parasite interactions. Though the effects of superparasitism and subsequent crowding on the parasite have been studied for some mermithids (Petersen 1972) and steinernematids (Sandner and Stanuszek 1971), no such observations have been reported for bark beetle parasites. During a survey of nematode parasites of bark beetles in Manitoba, we encountered two examples where nematodes were detrimentally affected at the higher infection rates observed. It was our objective, therefore, to examine the relationship between intensity of infection, and impact on growth and reproduction of the parasites.

Pristiphora harai sp.nov. collected on red spruce, Picea glehnii Masters, in Hokkaido is described, illustrated, and compared with P. ezomatsuvora Togashi.

We have developed a system for recording and quantifying animal behavior on artificial or natural substrates. The system is designed for subjects such as insects and mites with movement rates as high as 4 cm/min. The principle is the same as in automatic stage or sphere centering devices (Berg 1971; Kramer 1976; Thiery and Visser 1986), but the compensations are made manually by an observer who may also simultaneously enter codes for specific behaviors on a microcomputer keypad. Data files produced are analyzed or plotted using programs in SAS® (SAS Institute 1985a) or similar data analysis packages.

Glossina morsitans submorsitans Newstead has two pairs of autosomes, a pair of sex chromosomes (males are heterogametic), and from two to seven supernumerary (=B) chromosomes (Southern and Pel1 1973). The only information allowing assignment of loci to linkage groups in this subspecies is that electrophoretic evidence suggests that five polymorphic loci, including Est-2 and Mdh, are autosomal (Gooding 1984a), and breeding experiments indicate that sex ratio distortion, favoring production of females, is due to an X chromosome-linked factor (Gooding 1986).

Russian wheat aphid, Diuraphis noxia, was first detected in Canada in late July 1988 when a few were found on late-maturing spring cereals in southern Alberta near the International Boundary between Coutts and Aden. By the end of September, after dispersal or further immigration influx, it was widespread in Alberta south of Highway #3 and in southwestern Saskatchewan as far east as Swift Current. By mid-October more than 30% of the plants in many fields of winter wheat and fall rye in southern Alberta and up to 20% of plants in some fields of fall rye in southwestern Saskatchewan were infested. In November, Russian wheat aphid was also found on winter wheat in the Creston Valley of British Columbia.

The tarnished plant bug, Lygus lineolaris (P. de B.), is the dominant mirid in crops grown in eastern North America (Strong 1968; Bariola 1969). Lygus lineolaris is an ubiquitous species found on a wide range of wild plants and cultivated crops (Knight 1941).

All previously known egg parasitoids of Lygus spp. were mymarids in the genera Anaphes, Erythmelus, and Polynema (CIBC 1979). The mymarid Anaphes iole Girault is the principal egg parasitoid of Lygus spp. in the United States (Debolt 1987). It has been reported from British Columbia, Alberta, Ontario, Quebec, and the Northwest Territories(Huber and Rajakulendran 1988).