The emergence patterns of Diptera breeding in small-sized and buried carrion were studied in rearing experiments with field-exposed baits. Development times are reported for 52 species in the families Phoridae, Sphaeroceridae, Sepsidae, Heleomyzidae, Anthomyiidae, Fanniidae, Muscidae, Sarcophagidae, Psychodidae, and Sciaridae. Most species showed a synchronous emergence of males and females. Protandry was detected in Hydrotaea ignava (Harris) (Muscidae), H. palaestrica (Meigen), and Psychoda minuta (Banks) (Psychodidae). Protogyny was found in several species of Phoridae, namely Conicera similis (Haliday), C. schnittmanni Schmitz, Anevrina unispinosa (Zetterstedt), and Triphleba dudai (Schmitz). Conicera schnittmanni and T. dudai showed two discrete emergence periods for each sex, which is due to a delayed emergence of some specimens. Protogyny is a rare phenomenon in Diptera and insects in general, and has never been reported before in Phoridae. The significance of protogyny could not be ascertained in the examined species, because of insufficient information on their mating systems and female receptivity patterns.

During the course of genetic studies on the spruce and jack pine budworms, it was noted that there are distinct morphological characters on which the pupae and egg clusters may be separated. They are described here as a contribution towards the taxonomic separation of Choristoneura fumiferana (Clem.) and C. pinus Free.

A detailed analysis of male courtship behavior in Phodaga alticeps LeC. is presented. Although behavior in this species shares the basic pattern characterizing the subfamily Meloinae, several unique features are present. These include the mounted male being supported primarily by the substrate rather than the body of the female, and the anterior positioning of the male’s middle legs during most of the courtship period. Male stimulation of the female is tactual in nature and consists of periodically curling the antennae around those of the female and at the same time stimulating her maxillary palpi with the middle legs. Bouts of tactual display alternate throughout courtship with periods of male quiescence. Genital insertion attempts are rare in this species and probably occur only prior to copulation. Besides a description of male behavior the structural modifications functionally correlated with courtship are described; and concomitant female behavior and its effects on the male are discussed. In addition, the pattern of courtship in P. alticeps is compared to that of other meloids. Particular attention is given to behavior in its closest relative, Negalius marmoratus Casey.Other aspects of the bionomics of P. alticeps are also treated in this paper. Geographic distribution, seasonal distribution, feeding behavior, defense, antennal cleaning, and oviposition behavior are stressed.

From 1981 to 1984, a low-spray management program was employed against injurious arthropods on the 40 disease-resistant apple trees in my experimental orchard in Massachusetts. The program consisted of an annual early-season application of petroleum oil followed by 2 applications of phosmet (1 at petal fall and another 10–14 days later). Visual traps were used to suppress Rhagoletis pomonella flies. For all years combined, a mean of 89.7% of fruit sampled at harvest in this orchard was free of insect injury compared with 0% uninjured fruit on neighboring unsprayed trees. Populations of foliar-feeding pests never reached injurious levels.

Four species have been described in the apterus-group of the staphylinid genus Tachinus Gravenhorst. One of these, tundrae Poppius, is regarded as a synonym of brevipennis Sahlberg. Tachinus arcticus (Motschulsky) is recognized as a valid species, although earlier works have considered it a synonym of apterus. Tachinus brevipennis is recorded from the Nearctic Region for the first time. A neotype is designated for arcticus and lectotypes are designated for brevipennis and tundrae. Tachinus instabilis Mäklin is transferred to the apterus-group from the fimbriatus-group and recorded for the first time from Siberia. One new species, T. glacialis, is described from Siberia.

A key for identification of the species of the group and a description of the group characters are included. Each of the five species is described and the major diagnostic characters illustrated with scanning electron photomicrographs. A map is included to show the distribution of the species.

Feeding on leaders of resistant Sitka spruce trees, Picea sitchensis (Bong.) Carr., Led to ovarian regression in white pine weevils, Pissodes strobi Peck., that contained already mature eggs at the time of caging on leaders. Such feeding also led to inhibition or a virtual blockage of ovarian development in weevils that did not contain already mature eggs at the time of caging. Ovarian maturation in such weevils was restored by application of juvenile hormone to female weevils. Effects of three levels of resistance were consistent within the experiments and with the field performance of the tested clones. These results indicate that the effects of resistance were postingestive, i.e., resistance was a form of antibiosis. How antibiosis can cause the weevils to concentrate oviposition on susceptible trees is discussed. Results also provide a means of selecting and ranking resistance of individual spruce trees for tree breeding and reforestation.

One larval parasite, Aphaereta pallipes (Say) (Hymenoptera: Braconidae), and three pupal parasites (Muscidifurax raptor G. & S., Spalangia nigra Latr., and Eupteromalus dubius (Ashm.) (Hymenoptera: Pteromalidae)) developed on face fly, Musca autumnalis De G. (Diptera: Muscidae), collected near Belleville, Ont. These parasites, and four other Hymenoptera and one staphylinid, were reared from other Diptera associated with M. autumnalis. The economic value of the four face fly parasites is limited because only one (A. pallipes) finds hosts easily, none is host-specific, and few individuals that develop on face fly pupae emerge from the puparia.

Evidence is presented indicating that Harnischia Kieffer in the sense of Lenz is correct. Harnischia sensu Beck & Beck then becomes a synonym of Cryptocladopelma Lenz (which, however, is formally a nomen nudum). Synonyms of the genus Harnischia are given. Corrections and additions to the descriptions of Harnischia curtilamellata (Mall.) (syn. H. pseudosimplex Goetgh. syn. nov.) are given. The genus Harnischia is characterized. The phylogeny of the Harnischia complex is discussed.

Tests of sexual isolation indicate that, in the absence of temporal and spatial isolation, the strict mating behavior of the females and the high sexual aggressiveness of the males of Choristoneura fumiferana (Clem.) would obstruct any inward flow of genes from either C. occidentalis Free, or C. biennis Free. Under these same conditions, however, the two latter species may receive genes from C. fumiferana, since, in tests, their females mated indiscriminately and their males were less aggressive than those of C. fumiferana.

Field trials in northern Ontario in 1990 and 1991 confirmed that survival of spruce budworm larvae [Choristoneurafumiferana (Clemens)] (Lepidoptera: Tortricidae) parasitized by Apanteles fumiferanae Viereck (Hymenoptera: Braconidae) was greater than survival of nonparasitized budworm larvae following application of Bacillus thuringiensis var. kurstaki Berliner (Bt). Apparent parasitism by A. fumiferanae increased slightly when application of Bt was early (instar III or IV) but increased significantly when applications were later in the season (instars IV–VI). Delaying the timing of the spray conserved parasitoids while providing significant reductions in budworm densities and not compromising the primary objective of Bt application, i.e. the protection of current year foliage. The potential for long-term management of spruce budworm through the strategic integration of natural and imposed mortalities is discussed.

The influence of topical applications of fluorescent dyes or rubidium chloride (RbCl) solution, or both, on adult male spruce budworm longevity and attraction to and capture by pheromone-baited traps was investigated. Both marks persisted for at least 8 days in the field (duration of tests) and for at least 3 weeks in the laboratory. Recoveries of marked moths were similar to unmarked moths with respect to total recovery and timing and location (within the canopy) of recovery. The results validate the assumption implicit in previous mark–release–recapture studies on spruce budworm males that fluorescent dyes have no measurable effect on male trapping. A 0.41 M RbCl solution topically applied to laboratory-reared adult males is an efficient mass-marking technique for the spruce budworm.

Integration of pollinator-dependent invasive plants into native pollination networks can have direct and indirect effects on local plant and pollinator communities. Impacts on local plants are well documented; however effects on native pollinators have gained less attention. We examine these issues in habitat fragments of the endangered oak-savannah ecosystem in British Columbia, Canada. We measured pollen collection by native bumble bees (Bombus Latreille; Hymenoptera: Apidae) and the introduced honey bee (Apis mellifera Linnaeus; Hymenoptera: Apidae) foraging on two common native plants in habitat fragments with varying invasive (Cytisus scoparius (Linnaeus) Link; Fabaceae) density. The Bombus species with the largest workers had higher proportions of invasive pollen on their bodies and in their corbiculae than smaller workers. Honey bees rarely collected C. scoparius pollen. While some native bumble bees species collect an increasing proportion of C. scoparius pollen with increasing C. scoparius density, this did not translate into an increased potential for pollination. Rather, measures of effective pollination decline with C. scoparius density. Overall, our results suggest that some bee species may be better at finding resources at highly invaded sites. Apis mellifera is likely not playing a major role in facilitating the spread of C. scoparius in our region. Rather C. scoparius is visited by a complement of native bumble bees that are similar to pollinators in the native range of this plant.

We examined the within-crown distributions of male and female bagworm, Thyridopteryx ephemeraeformis (Haworth), pupae on Juniperus virginiana L. as a function of prior defoliation. This was to evaluate the hypothesis that the differential movement of females to the upper crown before pupation would be strongest on heavily defoliated trees. Differential stratification of the sexes occurred irrespective of degree of defoliation, and despite the fact that competition, as evidenced by higher mortality of pupae and reduced weight of egg masses, was apparently greatest at the top of moderately and severely defoliated hosts. There was no relationship between height of pupation and risk of parasitism for either sex. Female larvae were ca. 4-fold more likely than males to abandon a low-lying host upon which they had fed and to ascend the trunks of nearby trees before pupating. Enhancement of larval dispersal by females is the most plausible explanation for the stratified distribution of bagworm pupae within trees.

Hyperparasitism is a mortality factor that generally is beneficial to the continuous reproduction of the species involved.

The parasites of a primary parasite of a phytophagous insect may exhibit two distinctive types of secondary relations to that insect. These types are defined as follows:

Direct secondary parasitism: that type of host-parasite symbiosis where only the primary's parasitized host or the primary itself is attacked.

Indirect secondary parasitism: that type of host-parasite symbiosis where the primary's phytophagous host is attacked whether parasitized or not parasitized.

The host mortality caused by direct secondary parasitism may greatly exceed that caused by indirect secondary parasitism, this being manifested when the percentage of the primary parasitization of the phytophagous host is minimal.

Two viruses, one a nuclear polyhedrosis virus and the other a granulosis virus, were applied in an attempt to initiate epizootics in populations of western spruce budworm, Choristoneura occidentalis Freeman, on Douglas-fir trees, Pseudotsuga menziesii (Mirb.) Franco, in southeastern British Columbia. Two 172-ha plots were aerially treated in 1982 with 9.0 kg of lyophilized, virus-infected larval powder that was formulated in an emulsifiable oil tank mix and applied at 9.4 L per hectare. Each plot was treated when larval populations were at the peak of the fourth instar. The nuclear polyhedrosis virus was applied at 5.4 × 1011 polyhedral inclusion bodies per hectare and the granulosis virus at 1.7 × 1014 capsules per hectare. Results showed that the granulosis virus treatment caused 34.6% population reduction (Abbott’s formula) and the nuclear polyhedrosis virus 51.8%. Larvae from treated and check plots were reared individually in the laboratory and the incidence of viruses, parasitoids, and successful adult emergence was recorded. Studies m these plots continued in 1983 and 1984. Although vertical transmission of both viruses was evident, their impact on budworm mortality was less than in 1982. Consequently, the epizootics were not sufficiently intense to control the target insect population.

The tuber flea beetle, Epitrix tubrnis Gent., has been a pest of potatoes in the Fraser Valley and the lower mainland of British Columbia since 1940 (Glendenning, 1942); However, it was first reported from the interior in 1944, at Keremeos and Princeton and in the southern Okanagan Valley (Buckell, 1944). In 1945 and 1946, the first surveys were made to determine the area involved. The area and the degree of infestation have since increased anti1 it is now a very serious pest in the interior. The area of infestation is bounded by the International Border on the south and the Okanagan Valley on the east and extends northward to Malakwa. From here the line runs west through Adam's Lake to Barriere, to Criss Creek, to Pavillion, thence south to Lillooet, Lytton, Merritt, Princeton, and Hedley.

Several populations of the bagworm, Thyridopteryx ephemeraeformis (Haworth), were studied to determine the factors affecting survival of the larvae and pupae. Infestations were on Juniperus virginiana (juniper) and Thuja occidentalis (arborvitae). A normal complement of parasites, hyperparasites, and scavengers was recovered with four new records. The ichneumonid Itoplectis conquisitor (Say) accounted for most of the parasitism (75.9%). Females of this species were more often found in female hosts and males in male hosts. Although predation or larvae vacating bags were not directly observed, empty bags were found in each larval population beginning in mid-July and early August. The proportion of empty bags increased sharply from less than 10% to about 50% during a 3-week period but remained at this level for the rest of the season, suggesting that the bags were emptied during the first 3 weeks they were observed.

The pine needle miner (Exoteleia pinifoliella (Chamb.)) is one of at least seven pine needle miners occurring in North America. A native to the East, it is widely distributed from Southern Ontario (6) through the Atlantic States to Georgia (1).

The insect is a persistent and annoying pest that infests forest trees of all ages from nursery transplant beds to mature stands. The moths oviposit year after year on the same trees causing localized infestations; one part of a stand may be heavily populated, while an adjacent area may remain untouched for years.

The susceptibility of female spruce budworm moths to ULV aerial sprays of aminocarb and phosphamidon was dependent on the proportion of the total complement of eggs a female had laid. Females which laid few eggs were not killed by the insecticides whereas spent and almost-spent females were killed. Methods are described for determining the number of eggs a female has laid, the number of eggs she has to lay, and her total fecundity. These methods are used to evaluate the efficacy of ULV aerial sprays against budworm moths.