Field tests, using bolts of American elm trees either uninfested or infested with laboratory-reared or feral Hylurgopinus rufipes (Eichhoff), the native elm bark beetle, were conducted to evaluate colonization behavior of the beetle. The data confirm that (1) colonization of elm by H. rufipes can be accounted for by host attractants alone; (2) overwintered adult H. rufipes are attracted to broodwood (moribund or recently cut elm) in the spring, but summer-emergent adults are attracted to healthy elm; and (3) H. rufipes attacks broodwood primarily during evening beetle flights, and females initiate the gallery. A beetle-produced sex pheromone may be involved in the male–female pairing on broodwood.

Captive colonies of Bombus terricola Kirby received pollen for 8, 14, or 24 h per day from the time of onset of second brood oviposition until colony decline. The pattern of change of worker body size over time, especially between the first and second broods, varied according to these experimental food regimes. The results indicate that conflicting results reported in the literature, with respect to changes in worker size over the course of colony development, probably can be regarded, at least in part, as the outcome of differences in food supply.

A cardboard trap, painted yellow and coated with STP® oil treatment, was more efficient in trapping Myzus persicae (Sulzer) than water traps using Stickem®. STP-coated traps were more selective than Stickem-coated traps for small insects and caught more aphids per unit area than did water traps. Aphids were identified in situ on STP traps more quickly than from water traps or traps coated with Stickem.

Distribution of grasshopper populations was examined on a rural municipality (RM) basis over a 44-year period in Saskatchewan. A two-state Markov chain probability model was used to describe the transitional probabilities from high or low populations for different time steps. The analysis showed significant persistence of grasshopper populations in particular locations but the degree of persistence varied between RMs. The probability model was used to determine the expected duration of outbreaks or recessions. The potential usefulness of estimates of the expected duration of an outbreak is discussed in relation to crop protection.

The abundance levels of eight species of cutworms and army worms were monitored with sex-attractant traps at 81 locations in a 13 000-km2 area of southern Alberta from 1978 to 1983. Year-to-year change in population levels could be consistently detected by monitoring at a relatively small number of locations. For all species, subsets of selected locations along transects, or random subsets of as few as five locations, showed year-to-year fluctuations in mean catch per trap that were similar in pattern to those of the whole monitored area. The results indicate that long-term surveillance monitoring of pest species of cutworms and armyworms to detect year-to-year population changes, and long-term trends, is feasible in terms of both the resource requirements and reliability of the relative population estimates.

The fecundity and reproductive longevity of Schizaphis graminum (Rondani) parasitized by Lysiphlebus testaceipes (Cresson) were determined in the laboratory under four temperature regimes. Daily reproduction by S. graminum declined rapidly after parasitization except at a relatively low temperature regime (12–16 °C). The mean progeny production by parasitized aphids of 2.75 ± 0.08 nymphs per parasitized adult was not significantly different than that for unparasitized aphids (2.94 ± 0.23 nymphs) during the period of time equal to the reproductive life of parasitized aphids. Reproductive longevity of parasitized aphids was longest at the lowest temperature (5.67 ± 0.25 days at 12–16 °C). No significant differences were observed in total progeny produced at different temperatures. The number of progeny within parasitized nulliparous adults (3.37 ± 0.33) as determined by dissections was not significantly different from the mean total progeny produced by parasitized aphids. Parasitization thus seems to interfere with oogenesis, but not with embryonic development or progeny deposition.

The density and efficiency of bumble bees, honey bees, and alfalfa leafcutter bees on sainfoin, Onobrychis viciaefolia Scop., grown in southern Alberta were studied. Six species of bees were identified as pollinators, with alfalfa leafcutter bees comprising 56% of the observations, honey bees 40%, and bumble bees 4%. The density of flowers over the season can be described as curvilinear. The mean number of flowers per raceme decreased significantly over the season. The rate of foraging by pollinator species from flower to flower varied and is described by multiple regression models. Julian date, hour of day, and flower density are the independent variables. More than 90% of the bees visited three or fewer flowers per raceme when 60% of the racemes had three or more flowers available for pollination. The bees foraged on sainfoin for about 12 h per day and average bee density increased significantly with the corresponding flower density. A theoretical approach used to predict the bee populations required to pollinate varying flower densities shows that the required population of bumble bees is about two-thirds that of honey bees or alfalfa leafcutter bees. The observed populations of pollinators did not correspond well with the derived values, probably because multiple visits per flower are required for fertilization.

Data on the distribution of overwintering jack pine budworm (Choristoneura pinus pinus Free.) collected between 1985 and 1987 in northern Ontario are used to develop guidelines for sampling this stage of the budworm. Two alternative methods of expressing budworm density are considered: counting the number of budworms per metre of branch and counting the number per square metre of branch bark surface area. Estimates of budworm density for three levels in the tree’s crown are given for 4 site-years.

Entire branches are recommended as the sample units as the use of 60-cm branch-tip sections resulted in consistent underestimation of actual density per branch. Jack pine budworm density did not vary among cardinal compass directions and was generally highest at mid-crown levels.

The distributions of two parasitoids, Apanteles fumiferanae Vier. and Glypta fumiferanae (Vier.), which overwinter as an egg or first-instar larva within the jack pine budworm, also were considered. Apanteles was the most abundant parasitoid at all crown levels at all sites examined. Percentage parasitism by Apanteles was highest and that by Glypta was lowest on the branch-tip sections in relation to the branch-basal section, but total percentage parasitism was relatively constant over the entire branch, throughout the tree crown, and from tree to tree. Consequently, the sampling method for jack pine budworm is easily extended for estimating the rate of parasitism and therefore for providing a prediction of mortality that results from these two common parasitoids.

The seasonal damage to female reproductive structures (buds, flowers, and cones) of black spruce, Picea mariana (Mill.) B.S.P., was assessed during 1983 and 1984. Nineteen insects (five Orders) and the red squirrel, Tamiasciurus hudsonicus (Erxleben), were found feeding on these reproductive structures. Collectively, these organisms damaged 88.9 and 53.5% of the cones in 1983 and 1984, respectively. In the 2 years, Lepidoptera damaged 61.8% of the cones in 1983 and 44.4% of the cones in 1984. The spruce budworm, Choristoneura fumiferana (Clem.), and the spruce coneworm, Dioryctria reniculelloides Mut. and Mun., were the most important pests. Cones damaged by Lepidoptera could be classed into three categories: (a) severe, yielding no seeds; (b) moderate, yielding 22.3 seeds per cone; and (c) light, yielding 37.5 seeds per cone. Undamaged cones yielded on average 39.9 seeds per cone. Red squirrels removed 18.8% of the cones in 1983 and none in 1984. The spruce cone axis midge, Dasineura rachiphaga Tripp, and the spruce cone maggot, Lasiomma anthracinum (Czerny), caused minor damage in both years. Feeding by spruce cone axis midge did not reduce cone growth significantly or the number of viable seeds per cone, but feeding by the spruce cone maggot did. During both years new damage by insects to the female reproductive structures of the experimental trees was not observed after mid-July. In 1983 damage by red squirrels occurred from early to late September. In 1984 damage to cones on trees treated with dimethoate was 15.6% compared with 53.5% for untreated trees, without an increase in the number of aborted cones.

The control of the Colorado potato beetle, Leptinotarsa decemlineata (Say), by formulations of Bacillus thuringiensis (Berliner) (B.t.) and other microbial agents and chemical insecticides was assessed in field plots of potatoes and tomatoes over a 5-year period. Applications of formulations of thuringiensin, the beta exotoxin of B.t., and of B.t. var. son diego (B.t.sd.) to potatoes reduced numbers of larvae of the potato beetle compared with the nontreated check and resulted in yields significantly greater than from the check plots and, in most cases, similar to yields from plots treated with carbofuran. Treatment of tomatoes with B.t.sd. reduced populations of larvae of the Colorado potato beetle compared with the nontreated check and increased yield of nondamaged fruit from plots. An initial application of carbofuran to potatoes or permethrin to tomatoes followed by applications of thuringiensin or B.t.sd. protected potatoes or tomatoes as well as did the chemical insecticide used alone in a treatment program. Applications of preparations of B.t. var. kurstaki or spores of the fungus Beauveria bassiana (Balsamo) Vuillemin or the microsporidium Vairimorpha necatrix (Kramer) did not reduce populations of the beetle.

Ecological data, distribution records, comments, and diagnostic features are given for eight European species of Longitarsus Latreille introduced into North America: L. ferrugineus (Foudras); L. succineus (Foudras); L. luridus (Scopoli); L. jacobaeae (Waterhouse); L. ganglbaueri Heikertinger; L. pratensis (Panzer); L. pellucidus (Foudras); and L. rubiginosus (Foudras). The last two species are reported for the first time in North America.

Mortality of grasshopper eggs on the Canadian prairies is brought about by many factors, including winter temperatures. Although several authors (Parker 1930; Pickford 1966, 1976; Riegert 1967) have reported that winter temperatures can affect the mortality of grasshopper eggs, no quantitative data have been presented. This note reports the relationship between low temperatures and grasshopper egg mortality