Red and white clovers, Trifolium spp., were grown in nitrogen-poor soil containing cadavers of larval Galleria mellonella (L.) that were infected with Steinernema carpocapsae (Weiser) and its symbiont Xenorhabdus nematophilus Poinar and Thomas. Growth and root nodulation were not affected by the nematode treatment, leading us to conclude that they would not be impaired through the action of antimicrobial agents produced by Xenorhabdus spp. present in soils because of Xenorhabdus-infected insect cadavers.

We assessed enzyme variability in a solitary leafcutter bee, Megachile rotundata (Fabricius), and found sufficient variability to compare relatedness among progeny in a nest in two samples: (1) nests with an associated adult female (putative mother) and (2) nests with out-of-sequence male progeny (M. rotundata, like most cavity-nesting solitary aculeates, usually provisions all female cells in a nest before any male cells). Estimates of relatedness from nests with associated adult females were consistent with the progeny in a nest being closely related and the offspring of a single, once-mated female. The relatedness estimates from nests with out-of-sequence males were all much lower, suggesting some combination of nest parasitism, nest usurpation, nest abandonment, and multiply mated females in these nests. The high levels of relatedness among female progeny in the first sample, as expected for full sisters in a haplodiploid system, are considered with respect to the evolution of social behaviour in the Hymenoptera. Besides higher estimates of relatedness, the nests with an associated female also had a lower male:female sex ratio than did nests with out-of-sequence males.

The preference of the predatory midge, Feltiella acarisuga (Vallot), for adult male and female twospotted spider mite, Tetranychus urticae Koch, was examined using functional response models. The midge exhibited a type-II functional response to each prey. Handling time was estimated to be much higher for the female mites than for the males (1.52 vs. 0.40 h). Estimated instantaneous search rates for the female and male mites were similar (1.32 vs. 1.28). A preference index of 1.03 was calculated using the ratio of the instantaneous search rates. Feltiella acarisuga was found to exhibit no preference for either female or male mites; when both prey were present in equal numbers, midge larvae killed as many females as males.

Four steinernematid strains, Steinernema carpocapsae All strain, S. carpocapsae Umeå strain, S. feltiae Lie strain, and S. feltiae strain 27, were evaluated in laboratory and field tests as potential agents for the control of the black army cutworm, Actebia fennica (Tauscher). Although each of the six instars was susceptible to attack, incidences of infection were highest and generally over 60% for the third, fourth, and fifth instars when exposed to 100 infective juvenile nematodes in petri dishes. Fifth-instar larvae exposed for 1 week to soil containing 4000 infective juveniles in a 1:1:1 mixture of the L1c, All, and Umeå strains were most frequently infected with the L1c strain when reared at 10 and 12 °C and with the All strain when reared at 14 and 16 °C. One hundred thousand infective juveniles of the L1c, All, and Umeå strains and strain 27, alone and in various combinations, and applied by either a spray or soil-plug inoculation, killed black army cutworm larvae caged in the field for 1 week with treated black spruce seedlings and provided protection of current and 1 -year-old foliage. Treatments that included strain 27 provided the best protection when daily mean soil temperatures were 7–11 °C in comparison to treatments that included the Umeå or All strains, whereas treatments that included the All strain as a component appeared to be more effective than treatments containing the L1c and Umeå strains when daily mean soil temperatures were 16–17 °C.

Adult potato aphids, Macrosiphum euphorbiae (Thomas), caged on potato terminal leaflets treated systemically with imidacloprid solutions ranging between 5.4 × 10−4 and 5.4 × 10−8 mL per mL water showed a significant reduction in the distance they travelled, time taken to travel a given distance, and flight propensity but no significant differences in the frequency or duration of short probing behaviour. The frequency of adult apterous potato aphids colonizing untreated potato leaflets or leaflets treated with an imidacloprid solution (5.4 × 10−4 mL per mL water) was not significantly different, indicating no repellency. Potato aphids moving from systemically treated to untreated leaflets did not recover much and their reduced walking ability was maintained for days. A 3-day exposure to vapour from an imidacloprid solution (5.4 × 10−4 mL per mL water) did not produce significant mortality or changes in nymphal production. The daily cumulative mortality obtained by caging potato aphids on potato leaflets placed in an imidacloprid solution (5.4 × 10−7 mL per mL water) was similar to that obtained in the field, on 20-day-old plants treated at planting with imidacloprid applied at 0.02 g Ai/m. None of the rates of imidacloprid tested stimulated the dispersal of apterous or alate potato aphids.

Mayflies of the genus Ameletus (Ephemeroptera: Ameletidae) occur in practically every drainage of western Alberta and in the Cypress Hills, from headwater spring brooks to larger rivers. The genus is speciose and reaches its greatest diversity in the southwestern part of the province where as many as 12 species can occur at a single site. Of the 30 bisexual species currently recognized from North America, 13 have been collected from Alberta (A. bellulus, A. celer, A. cooki, A. majusculus, A. oregonensis, A. pritchardi, A. similior, A. sparsatus, A. subnotatus, A. suffusus, A. validus, A. velox, and A. vernalis), and another, A. inopinatus, is assumed to occur in the northern part of the province. Male adults of all North American species were described previously by Zloty (1996, The Canadian Entomologist128: 293–346). In the current paper, we describe late-instar larvae and adult females of all 14 Albertan species, and provide species distributions and keys for identification of male and female adults and larvae. All diagnostic taxonomic characters are described and illustrated. The identification keys can also be used in Saskatchewan, eastern British Columbia, Montana, and the northern parts of Idaho and Washington.

Synchrony of insect and host tree phenologies has often been suggested as an important factor influencing the susceptibility of white spruce, Picea glauca (Moench) Voss, and other hosts to the spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae). We evaluated this hypothesis by caging several cohorts of spruce budworm larvae on three white spruce populations at different phenological stages of the host trees, and then comparing budworm performance with host phenology and variation of 13 foliar traits. The beginning of the phenological window of susceptibility in white spruce occurs several weeks prior to budbreak, and the end of the window is sharply defined by the end of shoot growth. Performance was high for the earliest budworm cohorts that we tested. These larvae began feeding 3–4 weeks prior to budbreak and completed their larval development prior to the end of shoot elongation. Optimal synchrony occurred when emergence preceded budbreak by about 2 weeks. Larval survival was greater than 60% for individuals starting development 1–3 weeks prior to budbreak, but decreased to less than 10% for those starting development 2 or more weeks after budbreak and thus completing development after shoot elongation ceased. High performance by the budworm was most strongly correlated with high levels of foliar nitrogen, phosphorous, potassium, copper, sugars, and water and low levels of foliar calcium, phenolics, and toughness. These results suggest that advancing the usual phenological window of white spruce (i.e. advancing budbreak prior to larval emergence) or retarding budworm phenology can have a large negative effect on the spruce budworm’s population dynamics.

The exotic birch-leafmining sawflies Fenusa pusilla (Lepeletier), Profenusa thomsoni (Konow), and Heterarthrus nemoratus (Fallen) occurred in Alberta during 1992–1995, but only the first two were abundant. Birch-leafmining sawflies occurred at all sites surveyed in central and southern Alberta, and appeared to be expanding their ranges northward. Adult F. pusilla began emerging in mid-May (approximately 220 DD05), and there were one to three generations per year, depending on location and year. Female F. pusilla were relatively less abundant on young than on mature trees. Profenusa thomsoni began attacking trees in June (between 400 and 550 DD05), and was invariably univoltine. Both species were more abundant and were active earlier on urban trees than at a nearby rural location. The highest catches and most complete representations of seasonal activity were obtained using yellow sticky traps. Larval F. pusilla and P. thomsoni are unlikely to compete directly for leaf resources because their leafmining activities are separated spatially and temporally, but they probably compete intraspecifically.

Searching and ovipositional behaviors by female Eretmocems sp. nr. californicus Howard on Bemisia argentifolii Bellows and Perring infesting velvetleaf, Abutilon theophrasti Medic. (Malavaceae), and telegraph weed, Heterotheca grandiflora Nutt. (Asteraceae), were quantified. Adult female behaviors were described and quantified for E. sp. nr. californicus to establish a behavioral time budget analysis. Females departed from leaves of A. theophrasti in 83.3% of the trials, and of those that remained and searched for hosts, walking speeds averaged 0.29 mm/s. Females departed from the leaves of H. grandiflora in 44.4% of the trials, and those remaining readily searched for whitefly hosts with walking speeds averaging 0.26 mm/s. The duration of host assessment by antennation was related to subsequent behaviors; rejecting a host was a shorter process than accepting it for further evaluation irrespective of plant species or nymphal stage. Evidence for a behavioral preference for oviposition under early nymphal instars was documented for female E. sp. nr. californicus on both plant species. Oviposition efficiency in 1-h laboratory trials for nymphs on A. theophrasti was 30% and efficiency on H. grandiflora was 23%. Females spent 61.9 and 53.3% of their total time in searching, host assessment, probing, and oviposition while on A. theophrasti and H. grandiflora, respectively. The remainder of the time was spent grooming, resting, and host feeding, except host feeding on A. theophrasti was not observed. Implications of this study for silverleaf whitefly management through conservation and augmentation of native flora and fauna are discussed.

Visual responses of adults of Calosoma sycophanta L., which are predators of the gypsy moth, Lymantria dispar L. (Lepidoptera: Lymantriidae), were investigated in laboratory arenas. Beetles moved toward dark cylinders significantly faster than to light ones when the background was white, but no differently when the background was black. Thus, C. sycophanta appears to respond most readily to dark objects, and this response is only slightly modified by contrast with the background. Beetles move toward large-diameter black cylinders more readily than toward small-diameter ones, but object height and shape do not appear to be important characteristics. The visual responses of C. sycophanta would tend to orient adults toward the base of trees in a forest. Because beetles prey on gypsy moth larvae in trees, this orientation serves to position them where they can most readily find hosts, or perhaps to guide them to objects under which to hide.

From 1985 through 1995, burlap flaps were stapled to 100 trees in a 10 by 10 grid in a 4-ha forest plot. Each year, the number of fourth- to six-instar larvae of gypsy moth, Lymantria dispar L., under each burlap flap was recorded at least weekly in June and into July. From 1987 through 1990,100 000–120 000 hatching gypsy moth larvae were released near the center of this plot in early May at the time of natural hatch. In the 4 years that releases occurred, there was a distinct, single cluster of large larvae under the burlap flaps near the center of the plot. This pattern did not occur in other years. Results are interpreted to mean that total dispersal of larvae from first to ultimate instar is limited, even though first instars are readily dispersed by wind.

The commercial feeding stimulant Pheast® was tested in the laboratory to determine its attractive and phagostimulatory effects on larval Choristoneura rosaceana (Harris). In choice experiments, larvae were attracted initially to filter paper discs treated with Pheast, but did not remain on or near treated discs. Larvae were not attracted initially to raspberry leaf discs treated with Pheast, but were more likely to stay near treated leaf discs than water-dipped ones. Larvae were neither attracted to nor arrested on whole raspberry leaves treated with Pheast. In no-choice experiments, larvae fed Pheast-treated leaves consumed more leaf tissue than, and grew almost twice as quickly as, larvae fed leaves dipped in water. When larvae were fed leaves treated with Dipel WP (Bacillus thuringiensis var. kurstaki) plus 5% Pheast, the mortality was 93% greater than that of larvae fed leaves treated with Dipel WP alone. These results suggest that Pheast has potential to enhance efficacy of B. thuringiensis against C. rosaceana on raspberries in the field.

During a study on the importance of spiders as predators of the cabbage butterfly Artogeia rapae L. (Lepidoptera: Pieridae) in cultivated cruciferous fields in Quebec, 209 specimens (114 were immatures riding on the back of a female) of Trochosa ruricola (DeGeer) (Lycosidae), 21 specimens of Ostearius melanopygius (O. Pickard-Cambridge) (Linyphiidae), and one specimen of Dictyna decaprini Kaston (Dictynidae) were found by pitfall traps and aspirator at L'Acadie, Quebec (45°20'N, 73°20'W) in cabbage, Brussels sprouts, and broccoli plots. This is the first record of these species in Canada.

Cyphocleonus achates (Fahaeus) is a Eurasian, root-feeding weevil introduced into North America for the biological control of spotted knapweed, Centaurea maculosa Lamarck. Stinson et al. (1994) reported that C. achates is one of the most damaging root-feeding insects on knapweed in Eurasia and should be a valuable addition to the biocontrol effort in North America. The biology, host specificity, and potential impact of the weevil were described by Stinson et al. (1994). Larvae mine into the root cortex where they induce formation of a conspicuous root gall. Feeding by older larvae causes much damage, especially to small plants or plants containing several larvae. The weevil overwinters as a larva in the root and emerges as an adult from mid-July to October. Adult weevils are large (14 mm long) and flightless, and feed on knapweed foliage. The weevil has one generation per year.

Danausplexippus L. (Lepidoptera: Nymphalidae) is a cosmopolitan species, distributed in America wherever milkweed grows (Amett 1985). Its migratory phenomenon spans Canada, the United States, and Mexico and it has been considered endangered since the 1980s (IUCN 1983).

Ackery and Van-Wright (1984) compiled 45 species of food plants used by immature stages and 70 species of plants attractive to adults of the Monarch butterfly. Malcolm and Brower (1986) listed 28 host plant species recorded in nature. Lynch and Martin (1993) added six Asclepias species and observed larvae on three species of milkweed vine, Sarcostemma crispum and S. cynancroides in Texas, and Cynanchum laeve in Louisiana.

Listronotus montanus (Dietz) is a little known species, distributed in central North America. O'Brien and Wibmer (1982) record its occurrence from Indiana west to Nevada and north to the Prairie Provinces. In Montana, it occurs widely in grasslands east of the Continental Divide (Montana Entomological Collection, unpublished), but is also recorded from Saunders Co. in western Montana (Russell 1968). Nothing has been reported on the biology of this species, but it has been observed on grasses in the Cypress Hills of Alberta (CWOB unpublished). We report the occurrence of this species as a potential pest of small grains.