Lepidoptera larvae on highbush blueberry fed more frequently in flower and fruit clusters than in leafrolls during April, May, and early June. Their feeding reduced the harvest from individual clusters to about half of that of undamaged clusters. Larval feeding caused losses of production in blueberry fields of from 2.5 to 7% depending on leafroller densities. Insecticide treatments in experimental plots decreased leafroller populations and increased cluster yields.

Two species of opiine (Braconidae) parasitoids, Opius lectoides Gahan and O. downesi Gahan parasitized Rhagoletis zephyria Snow and R. pomonella (Walsh) in the Willamette Valley, OR. Almost equal numbers of O. lectoides and O. downesi were recorded from R. zephyria, whereas about 91% of the opiines associated with R. pomonella were O. downesi. In general, percent parasitization of R. pomonella was variable from sample to sample, but substantially higher on hawthorn than on apple fruit. It appears that both the opiine species have made a rapid host shift from R. zephyria to newly introduced populations of R. pomonella.

As part of a preimpoundment baseline study in the James Bay Hydroelectric Project in Northwestern Québec, systematic collections of aquatic insects were made in 1974 and 1975 in lakes and streams of the Rivière du Castor drainage. The aquatic Empididae are reported on here: they comprise 12 species, one of which is new (Hemerodromia fibrina n. sp.). Except for the boreal Metachela albipes, the fauna is remarkably temperate in character and composition. Emergence patterns are similar, though foreshortened, to those observed in southern Québec, and there are no bivoltine species. Most species are lotic and many thrive in fast waters (Neoplasm scapularis, Roederiodes recurvatus), but there is nevertheless a distinct lacustrine fauna (H. fibrina and perhaps also Chelifera rastrifera). The bog stations harbored only the widespread Chelifera palloris.

Representative aquatic insects, larvae of Simuliidae, Chironomidae, Trichoptera, Megaloptera, and nymphs of Ephemeroptera and Plecoptera, were tested for susceptibility to continuous exposure to Bacillus thuringiensis Berliner var. kurstaki at 4.3, 43, and 430 IU/mL. Only Simulium vittatum was affected, and at the highest concentration. Effects on other organisms, particularly Prosimulium fuscum/mixtum, were suggested. The lowest of the concentrations tested was twice the worst-case transitory concentration peaks expected in water from aerial forest spraying at 30 BIU/ha. Spray buffer zones around water bodies are unnecessary at this spray rate.

Data from 87 trees within 21 natural infestations were used to estimate the population size of the southern pine beetle (Dendroctonus flontalis Zimmermann) under collapsing high-level conditions in North Carolina. Spots of K trees (1<K<12) were created by random selection without replacement from the initial pool. Samples of m trees (1<m<K) were then chosen from each simulated spot according to random and selective plans. These samples over m trees were then extrapolated to the full K tree spot by 1 of 3 scaling factors: percentage of trees sampled, percentage of diameter sampled, or percentage of phloem area sampled. In this manner the total numbers of parent adults, brood, and brood adults were estimated for each artificial spot. Proportional errors, defined as (observed value – expected value)/(observed value), were computed over 10 000 independent trials for a variety of sample sizes, spot sizes, and scaling factors. The precision of these errors, after a bias correction was applied, was used to compare the different schemes. Random-diameter and largest-diameter schemes were judged best because of their good precisions and ease of application. However, when these results were applied to the 21 natural infestations, the confidence intervals were found to be too narrow to include the expected number of estimates. A discussion of this shortcoming is discussed in relation to spot dynamics and its effect on the application of this sampling technique.

Microctonus vittatae Mues. oviposit in the hemolymph of flea beetles, Phyllotreta striolata (F.) and Phyllotreta cruciferae (Goeze), by inserting the ovipositor into the host's mouth and occasionally, membranous areas between body segments. Some of the eggs are transported in the hemolymph posteriorly from the head to the thorax or abdomen, and some laid in the thorax are carried into the abdomen, but eggs hatch in all 3 body regions of the hosts. First-instar larvae that eclose in the head and thorax disperse into the abdomen where they develop. Egg and larval dispersal into the abdomen increase the probability that the parasite has adequate space for development.

The influence of nitrogen levels in foliage of white-fir, Abies concolor, and Douglas-fir, Pseudotsuga menziesii, seedlings on various biological characteristics of the western spruce budworm, Choristoneura occidentalis Freeman, was studied. Seedlings were grown under greenhouse conditions and provided with nutrient solutions to maintain five foliar nitrogen levels ranging from 1.29 to 4.42% dry weight for white fir and 1.43 to 3.94% for Douglas fir. Larvae confined to treated seedlings were monitored through the next generation. Larval mortality was higher, and development time longer, at both upper and lower extremes of foliar nitrogen than at mid-level. Mean pupal weight was significantly greater for larvae reared on white fir with the mid-range foliar-nitrogen level. Mean number, and weight, of eggs laid were highest when larvae fed on foliage from the mid-range nitrogen level. Total number of larvae produced was lowest at the high and low extremes of foliar nitrogen levels.

Cypermethrin was more toxic to adults of the tarnished plant bug, Lygus lineolaris Palisot de Beauvois, in both laboratory and field studies, than other synthetic pyrethroid, organophosphorus, or chlorinated-hydrocarbon insecticides. The synthetic pyrethroids were more toxic than other groups of insecticides. Residues of cypermethrin were toxic to plant bugs for 7–10 days; other compounds were effective for shorter periods. In the field 1 application of cypermethrin effectively controlled tarnished plant bugs on peach.

Early removal of the alfalfa canopy not only reduced the population density of Agromyza frontella (Rond.) by the elimination of partially developed larvae, but also by increasing mortality of individuals that had already evacuated their mines. This mortality was associated with increased temperatures and/or decreased humidity of the soil, as most pupae are found close to the surface due to the limited burrowing capacity of prepupae. Harvesting data should be included in predictive models, as this parameter affects both the number and time of adult emergence.

Field-screening tests using dodecenyl and dodecadienyl acetates and alcohols were conducted in pine plantations in northern Ontario to find attractants for Rhyacionia and Eucosma moths. Rhyacionia adana was attracted by various ratios of (E)-9-dodecenyl acetate and (E)-9-dodecen-1-ol (99:1 to 70:30) but no clear preference was observed. Similarly, R. busckana was also attracted to the same ratios of these compounds. Rhyacionia granti Miller, a new species revealed by these tests, was attracted to (E,E)-8.10-dodecadienyl acetate. Rhyacionia granti and R. busckana are newly recognized sibling species distinguished in this study by differences in their respective attractants, EAG responses, and phenologies. The fourth species studied. E. gloriola, was optimally attracted by 9:1 and 8:2 ratios of (Z)-9-dodecenyl acetate and (E)-9-dodecenyl acetate. Flight data for the 4 species in the same plantation revealed overlapping flight periods. Rhyacionia granti was the earliest flier, followed closely by R. adana and R. busckana, and somewhat later by E. gloriola.

Detailed generic descriptions are given for the adult male and female, larva, and pupa of Xylotopus Oliver and for the adult male of Irisobrillia n. gen. Two new species, Xylotopus burmanensis and Irisobrillia longicosta, are described. A key is presented to separate adult males of Xylotopus and Irisobrillia from allied genera, Brillia Kieffer, Eurycnemus Wulp, and Euryhapsis Oliver.

Norwegian pipe traps, used with pheromones to mass-trap Ips typographus (L.) in Scandinavia, were used in central British Columbia to determine whether any native beetles would respond to the pheromone of I. typographus. The spruce-infesting Ips tridens (Mannerheim) was the only species captured. Traps baited with “Ipslure” packets (1400 mg 2-methyl-3-buten-2-ol, 70 mg (S)-(−)-cis-verbenol, 15 mg racemic ipsdienol), ipsdienol, or ipsdienol plus cis-verbenol, caught significantly more beetles than unbaited traps. cis-Verbenol, which attracted no beetles when used alone, acted synergistically when added to ipsdienol. Methylbutenol used alone was no more attractive to beetles than the control, and inhibited the response of female beetles when added to traps baited with ipsdienol or ipsdienol plus cis-verbenol. Ipsenol alone attracted no beetles. The sex ratios of responding beetles (mean 1 male: 7.15 females) did not differ among treatments, but all differed significantly from the ratio of 1 male: 3.12 female beetles emerging from naturally infested spruce bolts.

Predation on spruce-budworm, Choristoneura fumiferana (Clem.), pupae on the forest floor was estimated at 72.5% per day. It is unlikely that many adults of the spruce budworm emerge from the forest floor and there would be little bias introduced in the estimation of apparent fecundity by disregarding pupae on the ground. There were large seasonal fluctuations in the rate of predation attributable to various predator groups; the overall rate ranged from 66 to 91% per day. Low temperatures had no detectable effect on vertebrate predation, but reduced invertebrate predation; however, this effect is unlikely to result in much variation in survival of pupae on the forest floor.

The insect parasite Cotesia rubecula (Marshall) shows a long-day, photoperiodic response that results in diapause in the eonymph. Within the region of the critical photoperiod, the diapause response is modified by temperature and by the duration of the developmental period of the larval parasite, but in field populations in Vancouver, diapause is predominantly a response to short photoperiods. There is evidence that the parasite's response is largely independent of the host's response. Once diapause is induced, there is an obligatory dormant period of at least 2 months after which diapause terminates when specific-heat requirements are fulfilled. The estimated heat requirements are used to predict the date of diapause termination and the emergence of parasite adults in the field. Parasite activity begins almost 6 weeks after that of its host.

The critical photoperiod for populations in Vancouver, Canada, lies between 15- and 16-h photophase but in Canberra, Australia, the critical photoperiod is less than 13 h. The significance of this difference in the diapause response of the 2 introduced populations is discussed and recommendations are made for further biocontrol efforts.

Chrysopidae in Canada comprise 24 species in 9 genera and 2 subfamilies. Additional southern species are mentioned, 1 as a new combination, and other nomenclatorial changes are reviewed in relation to the Canadian fauna. Generic diagnosis of males employs sternum VIII + IX, the arcessus, gonapsis, pseudopenis, and tignum. Generic diagnosis of females is based on the dorsal furrow, ectoprocts, spermatheca, subgenitale, and a non-genitalic trait, the innermost gradate crossvein in the wings. The ecological implications and inherent difficulties in taxonomy are discussed for coloration in Chrysopidae, to develop a practical key to differentiate 26 species using color and other non-genitalic traits. A checklist summarizes maps of the geographic distribution in Canada and notes species in Alaska, based on specimens examined. Patterns of distribution for the Canadian chrysopid fauna are either Holarctic for 1 species or indigenously Nearctic, with eastern, western, or boreal foci. Disjunctions are apparent for species with a more southern, transcontinental distribution, which enter Canada primarily in Ontario and British Columbia. Life-history and bionomic notes are limited to 6 species in Canada, for which synonymies and figures are based on specimens examined. Most data originate from studies performed in Ontario. There are 5 species of parasites from 2 chrysopids. Hosts include 11 species of insects and mites, with 2 cases of hyperpredation. Three insecticides account for the more recent scarcity of chrysopids in the Niagara region. Conclusions relate the following: variable color in the 1 Holarctic species to post-glacial mingling in the northwest; gaps in temporal and spatial distribution to extinctions in progress; and renewed interest in Chrysopidae to earlier research on this group in Canada.

Simple, sticky traps were used to monitor adult sciarid populations, and soil cores were used to monitor larval sciarid populations in commercial cucumber greenhouses. Four methods of sticky-trap placement were compared and it was found that 5 traps in a “W” formation correlated closely with more intensive 12- and 30-trap random placements. All 4 of the greenhouses studied exhibited similar sciarid population patterns in 1983 but only 2 showed large sciarid populations in 1984 and the other 2, using different overwinter sanitation methods, had no detectable sciarid populations. Moth-flies (Psychodidae) were often the most numerous form of small dipteran found on the traps. Larval sciarids occurred in the upper 5 cm of each 10-cucumber bag, and weekly 50-mL core samples showed a range of 0.0 to 1.1 larvae/mL which corresponded to estimated larval populations of up to 2500 per bag. Plants that had succumbed to fungal pathogens and then been sampled immediately for sciarid larvae were found to have fewer larvae per bag than apparently healthy plants. Insect monitoring in cucumber greenhouses has enabled growers to reduce and/or eliminate the need for insecticide applications against sciarids during the growing season.

The numbers of Douglas-fir tussock moths (Orgyia pseudotsugata) (Lepidoptera: Lymantriidae) caught in sticky, delta-shaped pheromone traps baited with different concentrations of synthetic lures were compared with egg-mass densities and subsequent defoliation throughout a population cycle. A lure containing 0.01% pheromone by weight in the form of a 3 × 5-mm polyvinylchloride rod provided more consistent catches than pheromone concentrations of 0.0001, 0.001, 0.1, or 1.0%. Trap saturation occurred when >40 moths per trap were caught. To achieve a standard error of 30%, 6 traps were required at each site. There was a poor correlation between numbers of moths caught and egg-mass density or defoliation estimates in the following generation, but a threshold density was found that provides a warning of an incipient outbreak. Ground surveys for egg masses are recommended to confirm suspected infestations after continuous increases in moth catches for 2 to 3 years or if an average of 25 moths or more per trap has been caught.

The life cycle, feeding behavior, and feeding damage of the spruce budmoth, Zeiraphera canadensis, were studied in northern New Brunswick. Larval emergence, which began in late May, was usually completed within 10 days. First-instar larvae did not feed on the previous year's foliage and took less than 30 min to settle inside a growing shoot, from which they exited only at the end of larval development. Larvae then dropped to the ground and remained as prepupae for approximately 6 days. Mating could be observed the first night following adult emergence. The majority of the mated females contained only 1 spermatophore (92%); others had 2 (7%) or 3 (1%). Although 95% of the egg clusters had 7 eggs or less, 5% had up to 19 eggs. Eggs required embryonic development before successful diapause could be initiated. The importance of these observations in the development of management strategies for this pest is discussed.

The New World species of Trissolcus, exclusive of the flavipes and thyantae species groups, are revised. This encompasses seven species: T. basalis (Wollaston) recorded in the southeastern USA, West Indies, Venezuela, and southeastern Brazil; T. cosmopeplae (Gahan) from the USA and Canada; T. erugatus n. sp. from the western USA and Canada; T. hullensis (Harrington) widely distributed throughout Canada, USA, Mexico, Dominica, and Venezuela; T. radix n. sp. from Guatemala, Costa Rica, Colombia, Venezuela, and the southeastern USA; T. solocis n. sp. from Mexico and the southeastern USA; and T. utahensis (Ashmead) from the western USA and Canada. Available host information for each species is summarized. These species are described and an identification key is provided.

During 1983, collections and observations of the half-wing geometer, Phigalia titea (Cramer), were made in 2 counties of eastern West Virginia where the species had caused heavy defoliation of hardwoods in the previous 2 years. Larvae were observed on 41 species of host plants in the field. Host–plant evaluations for 69 species were made in the laboratory with 1st-instar larvae. According to criteria of response/developmental time of larvae, 33 plants were categorized as highly acceptable, 12 as acceptable, 20 as unacceptable, and 4 as toxic.