The efficacy of seven chemical insecticides, five commercial preparations of Bacillus thuringiensis, and two preparations containing diatom dust were tested against the European skipper, Thymelicus lineola (Ochs.), under field conditions. Satisfactory control was obtained with carbaryl, carbofuran, methomyl, permethrin, trichlorfon, Dipel 45B(=Dipel SC), Dipel WP, Thuricide 26B, Thuricide HPC, and Novabac 3 while dimethoate, chlorpyrifos, and the diatom dusts afforded little or no foliage protection. While larval mortality occurred less rapidly when B. thuringiensis preparations were applied, their use is strongly recommended as they afford the same degree of foliage protection as chemical insecticides and diminish possible undesirable off-target effects.

Comparison of yolk protein deposition rates as inferred from rates of leucine incorporation in ovarial yolk proteins was made between Dendroctonus rufipennis caged on living white spruce trees and freshly cut logs of the same species. Samples coinciding with resin exudation into the beetle galleries by the living tree revealed significant inhibition of this rate as compared with that observed on cut logs. These results constitute a clear example of the effect of a specific event in the tree on the reproductive processes of the adult beetle. Advantages of measuring rate of yolk deposition over counting total oviposition for determining the effect of various factors on reproduction are discussed.

The spermatophores in mated female European corn borers, Ostrinia nubilalis (Hübner), were shown to lose volume (depletion), change colour, and retract their spiral stalks over a period of about 7 days in such a way that postmating age could be estimated from their appearance. Colour changes and stalk retraction occurred more slowly in females that laid fertile eggs than in those that did not, but depletion occurred at the same rate. The average postmating age was estimated as 5.2, 6.3, 3.9, and 2.6 days for small light trap catches of first generation females in 1974, 1975, 1976, and 1977 and 4.4, 3.9, and 3.2 days for larger catches of second generation females in 1974, 1975, and 1977. Catches did not show decreasing numbers in successive age groups but tended to show modal values at < 1 day and at 4–6 days with only 1% living > 7 days. Redistribution of the moths from the date of capture back to the date of mating tended to give a unimodal curve of numbers on time in the 1975 second generation but not in 1974 or 1977. The unimodal curve of redistributed moths in 1975 was significantly different from a normal distribution. The redistribution showed that 58% of the moths mated within the heat unit interval when the second generation was expected to emerge, whereas only 38% of the actual catches occurred in this interval. Redistribution also showed that mating probably occurred even on cold nights when few moths were trapped, and conversely that on some warm nights with large catches most of the moths had mated on earlier nights.

A study on techniques for rearing Glischrochilus quadrisignatus (Say) in the laboratory showed that provision of adequate moisture and control of fungal diseases were essential. Most field-collected adult females oviposited regardless of when the collections were made, but there were large variations in the preoviposition periods. Hibernating beetles collected in the spring had a much shorter preoviposition period than beetles collected in the autumn and early winter. The high viability of eggs laid by overwintering females kept separate from males indicated that the beetles mated in the fall. Three consecutive generations occurred when beetles were reared in crocks supplied with corn and tomatoes in a greenhouse. At 21°C, the incubation period for eggs averaged 4.1 days, the larval period 21–22 days, and the pupation period 11.8 days. Newly developed adults remained in the soil for an average of 11.2 days before emerging.

Phyllotreta cruciferae (Goeze) was usually the most abundant flea beetle on crops of Argentine rape, Brassica napus L., in Manitoba, followed in order by Phyllotreta striolata (F.) and Psylliodes punctulata Melsh. These three species and small numbers of Phyllotreta bipustulata (F.) were present on volunteer rape in the spring. A few specimens of a fifth rape-eating species, Phyllotreta robusta Lee, were trapped in April after hibernating. The three main species were recorded in all 16 localities in which samples of flea beetles on rape crops and/or volunteer rape were collected. Details of seasonal life history of each species are presented, as well as data on the abundance of the three main species throughout the year on rape crops, in overwintering habitats and on volunteer rape in spring. The relative abundance of P. cruciferae, P. striolata, and Ps. punctulata in different rape-growing areas of Manitoba is discussed.

The antiaggregation pheroraone MCH was ineffective in preventing spruce beetle infestation in felled spruce near Hope, Alaska. In October, most progeny were larvae but some were pupae and new adults. Densities of spruce beetle attacks and progeny on the shaded under side of stems were about twice those on the upper side, whereas attacks of Polygraphus rufipennis (Kirby) and Dryocoetes affaber (Mann.) on the upper side were 100 times those on the under side. Ips tridens engelmanni Swain was present in only 2% of bark samples. Entomophagous insects were scarce; only Medetera sp. and Coeloides sp. were found. Spruce beetle progeny were 45 times more abundant than attacking parents. Factors affecting the efficiency of sampling spruce beetle attacks and progeny are discussed.

Dosage–response relationships of seven insect growth regulators (IGRs) to last instar western spruce budworm, Choristoneura occidentalis Freeman, were determined by topical application, spray application, and diet incorporation bioassays. Mortality was defined as failure to emerge as a viable adult. In spray application experiments, four IGRs—ZR-512, ZR-619, ZR-1662, and Ro 10-3108—had LD50s of less than 70 g/ha (1 oz/acre). Relative lethal effectiveness, based on a simple model combining data from the three bioassays, was ZR-1662 > ZR-619 > ZR-512 > Ro 10-3108 > ZR-777 > ZR-587 > ZR-515. We concluded that several IGRs, applied to a population consisting primarily of last instars, would induce lethal effects at dosages comparable to dosages of several conventional insecticides.

The fecundity and fertility of parent adult western spruce budworm, Choristoneura occidentalis Freeman, which survived treatment with IGRs in their last larval stage was assessed. With few exceptions, IGR treatment significantly reduced both reproductive factors regardless of whether the male or female parent had been treated. A simple model estimating population reduction in the F1-generation based on lethal and reproductive effects on the parents is described. If IGRs were applied at a dosage of 154 g/ha (ca. 2 oz/acre), the estimated percentages of F1 reduction which would result ranged from 74.6 (ZR-515) to 99+ (ZR-512 and Ro 10-3108 (oil)).

Blacklight traps were used for monitoring flight activity of Phyllophaga anxia (LeConte) in southern Quebec. Adults began flying during the last 3 weeks of May and flight terminated about the end of June, depending on the season and the locality. The adults required approximately 176 degree-days accumulated above a base of 5 °C for flying to commence. Peak flight occurred late in May or in early June. Both sexes were attracted to blacklight traps.

A modified Ladell apparatus is described which offers a low cost and efficient method of wetland macroinvertebrate extraction. Soil and leaf litter samples, immersed in Mg2SO4 solution, are subjected to agitation and bubbling to promote the extraction of macroinvertebrates. A further modification provides salt solution recycling. Fourteen floodplain taxa were recovered with extraction efficiencies ranging from 80 to 100% at a cost of 15–20 cents (U.S.) per sample.

The biology of the crucifer flea beetle, Phyllotreta cruciferae (Goeze), was studied in the laboratory, and under field conditions in southwestern Ontario. Field-collected adults, held in a state of induced hibernation were used for some laboratory studies. A rearing procedure was developed and a culture maintained for eight generations provided additional adults for laboratory work. Development and behaviour of the various crucifer flea beetle stages at different temperatures were studied. The mean preoviposition period ranged from 3.8 (32°C) to 22 (20°C) days. Time required for development from egg to adult varied from 24 (30°C) to 54 (20°C) days. For oviposition capability and egg to adult development, developmental thresholds were ca. 17° and 11°C, respectively, and 61 and 456 degree days were required. Crucifer flea beetle adults overwintered in leaf litter and the top 2.5 cm of soil, in windbreaks, fencerows, and cultivated areas. Adults appeared in early spring. Peak adult movement occurred at this time, primarily within 2 m of the ground, and oriented toward crucifer plots. Using heat unit summations calculated from soil temperatures, adult emergence in the field from eggs set out at various times was predicted with an accuracy of ± 3.7 days. Population studies and heat unit accumulations indicated that there was a single generation of crucifer flea beetle in 1974, and two generations in 1975. Adults were restricted primarily to cruciferous crops, with rutabaga and Chinese cabbage being the preferred hosts, among those varieties tested.