Insect-detection traps baited with the synthetic aggregation pheromones of the rusty grain beetle, Cryptolestes ferrugineus (Stephens), were inserted into grain stored in primary elevator annex bins and in farm bins, or suspended in partly full or empty bins and outside under the eaves of bins. The mixture of the synthetic pheromones 4,8-dimethyl-E,E-4,8-decadienolide (ferrulactone I) and (Z)-3-dodecen-11-olide (ferrulactone II) was released from hollow polyester fibers (0.203 mm ID) positioned in the interior of the insect-detection trap. In annex bins, the number of beetles found in baited traps after 1 week ranged from 0 to 7300. In these bins, more beetles were found in traps at a depth of 30–60 cm than at 150–250 cm, and in traps with 2 fibers containing pheromone rather than with 1 fiber. In farm bins, baited and unbaited traps were relatively ineffective at grain temperatures below 14 °C. More beetles were found in baited than in unbaited traps in farm bins but the numbers were small and the differences were not significant. Few beetles were found in traps suspended in partly full or empty farm bins and none in traps suspended outside under the eaves.

The growth and yield responses of “Totem” strawberries, Fragaria × ananassa, to 4 introduction densities of the twospotted spider mite, Tetranychus urticae Koch, were observed under field conditions in the lower Fraser Valley. At the high-density treatments T. urticae populations peaked at 65 mites/leaflet and declined during harvest. At the medium- and low-density treatments and in the controls, T. urticae had lower and later peaks. Two species of insect predators and 1 phytoseiid species preyed upon T. urticae. Berry weight and number were predicted (R = 0.97, 12 df) from the number of flowering stalks and accumulated mite-days. Yields increased with increasing numbers of flowering stalks and declined with increasing accumulated mite-days. A $1300 yield loss/ha was observed when 2500 mite-days accumulated between 15 May and 16 July. Fruit size was not affected by T. urticae. Yield equations were developed so that a mite sample 1–5 weeks before harvest can be used to predict dollars lost due to T. urticae. The data allow the grower to determine an economic threshold based on the number of weeks before harvest, mite sample precision, differences in environmental conditions relative to the present study, the control measure to be used, and the market price to the grower.

The life stages of Phyllonorycter blancardella (Fabr.) were monitored in an orchard at Guelph, Ontario in 1981 and 1982 and the results showed discrepancies with the previous concept of a trivoltine species occurring throughout its range in eastern North America. Sleeve cages were used to monitor the development of the second, mid-summer generation of leaf miners in a low-maintenance orchard at Guelph in 1982 and 1984 and 2 commercial orchards at Simcoe, Ontario in 1984. The flight period of the first-generation adults occurred over approximately a 6-week period. From eggs laid early in the flight period, a large proportion of the larvae developed quickly and emerged to give a second-generation adult flight. As the flight period continued, there was an increase in the number of progeny whose development was delayed in the early instars. These larvae did not pupate until late fall and overwintered as pupae. Of the second-generation larvae, about 70–90% at Guelph and 35% at Simcoe had a delayed development (summer diapause) and formed a large proportion of the overwintering population.

Second- and 3rd-instar nymphs of Melanoplus sanguinipes (Fab.) were more susceptible to Nosema cuneatum Henry infection than were 5th-instar nymphs. Lethal times were significantly lower for 2nd- and 3rd-instar nymphs inoculated with 1.0 × 106 and 104N. cuneatum spores/individual than for similarly treated 5th-instar nymphs and a much higher percentage of the latter were uninfected at the end of the experimental period (40–60 days post-inoculation). Fifth-instar nymphs inoculated with 1.0 × 106 spores/individual showed reduced adult longevity. The number of eggs laid per female was not significantly different for inoculated or untreated 5th-instar nymphs. However, the dry weights of eggs laid by inoculated grasshoppers were significantly lower and fewer eggs hatched than for those laid by untreated grasshoppers. Twenty to 30% of the progeny from inoculated 5th-instar nymphs had detectable levels of N. cuneatum sporoblasts and spores.

Section 7 of the primary simplex of the ductus ejaculatorius of unmated male spruce bud worm moths, Choristoneura fumiferana, contains a yellow substance that is not present in recently mated males. The yellow substance occurs in laboratory-colony males reared on diet and in feral males reared on foliage. It is shown that the presence/absence of this material is a reliable index of copulation during the previous 24 h. Although the yellow substance regenerates over a period of several days, males 0–72 h post-copulation may be indexed when compared with unmated males of similar age.

Four genera and 9 species of ants were collected by pitfall traps in a spruce budworm-infested forest of northern Maine. Myrmica detritinodis and Camponotus herculeanus were most abundant. In 1977, significantly more individuals and species were trapped in dense spruce-fir stands than in either uncut residual or clearcut strips. In 1978, clearcut-strip and dense-stand means were nonsignificant for individuals and species, but significantly more individuals and species were trapped in clearcut than in uncut residual strips. Ants were active during the spruce budworm’s developmental stages. Diversity of ant species was generally greater in dense stands than in strip-clearcut areas. Individuals were distributed unevenly among species but more evenly in dense stands than in strip-clearcut areas (residual + clearcut strips). Coefficients of community (CC) and percentage similarity (PS) values indicated ant species and individuals shared forest conditions in common; however, the most dissimilar neighboring habitats (uncut residual and clearcut strips) had few species in common. Neither age of strip clearcut (1–6 years) nor litter depth had much influence on mean catches and mean number of species of ants/trap/week.

The “new approach” to selecting biological control agents, as proposed by Hokkanen and Pimentel in 1984, through the use of new exploiter–victim associations is inappropriate for the biological control of weeds because of certain misconceptions in their method. Examples of biological control of weeds cited in their analysis were biased towards cactaceous insects, and cacti are not representative of target weeds. Several of their “new” associations were inaccurate. These inaccuracies are discussed and additional examples are provided to refute the proposed method. Contrary to the recommendation of Hokkanen and Pimentel, new exploiter-victim associations offer limited opportunities for biological control of non-cactaceous weeds with insects, and should not be used as the preferred method in selecting biotic agents for the biological control of weeds.

Emergence patterns, sex ratios, and dispersal characteristics of Ips typographus L. (Coleoptera: Scolytidae) emerging from hibernation sites were studied under field conditions. A total of 8666 emerging beetles were caught in 14 tent-traps, covering brood tree stumps at 3 different hibernation sites. Samples of these beetles were sexed at frequent intervals. The proportion of females increased as emergence progressed and the overall proportion of females was 62%. A total of 3433 beetles emerging after hibernation were marked and released on 19 separate occasions. The recapture rates were 13 and 4% in nearby and distant pheromone traps, respectively. Recaptures were recorded at distances of up to 1800 m. Beetles were able to respond and fly to pheromone sources shortly after emergence without prior feeding or prolonged flight activity. Trapping and marking techniques, temporal and spatial emergence patterns, seasonal sex ratio changes, and factors influencing pheromone trap catches are discussed.

Fenitrothion accumulates in foliage tissue of balsam fir, Abies balsamea (L.) Mill., in the forest, but only until about 1.5 μg/g is reached. The balsam fir sawfly, Neodiprion abietis (Harris), which belongs to the family of forest insects known to be most sensitive to fenitrothion, has become rare but persists in New Brunswick in spite of the use of fenitrothion for control of spruce bud worm, Choristoneura fumerifana (Clemens).

In 1982, the synthetic pyrethroid, cypermethrin, was among the insecticides recommended as a spray for control of adult flea beetles attacking canola crops in Saskatchewan (Saskatchewan Agriculture 1982). Growers reported some problems with its effectiveness at the recommended rates of 14–20 g AI/ha, however, and the recommendation for its use against flea beetles was subsequently discontinued. Laboratory spray trials were begun in 1982 to determine if post-treatment temperature affected the contact toxicity of cypermethrin to adults of the major pest species, Phyllotreta cruciferae (Goeze), and if the dosage that had been recommended was adequate as a contact spray.