The woolly-bear caterpillars of Grammia (= Apantesis) blakei (Grt.) are sometimes abundant on native range pastures in the short-grass region of southern Alberta and southwestern Saskatchewan and occasionally cause early season damage to adjacent cultivated crops. The larvae overwinter as mid- to late-instars in protected sites on the soil surface and begin feeding in the spring as soon as new plant growth is available. They are general feeders on both mono- and dicotyledonous plants. Larval densities exceeding 10/m2 were found at several locations from 1982 to 1985 and historical records indicate that densities sometimes exceed 50/m2. The moths are present in late May through June but are rarely observed or collected. In Canada the species is univoltine with a mid-larval summer diapause.

Cystiphora sonchi (Bremi) females, fixed while ovipositing into leaves of perennial sowthistle (Sonchus arvensis L.), were sectioned and then examined with a light microscope. Sections revealed that this gall-inducing species oviposited into leaves of sowthistle via the stomatal openings of the lower epidermis. Furthermore, sections of eggs and surrounding leaf tissues indicated that the epidermis was not punctured during oviposition.

Hypericum perforatum L., St. John's - wort (Hypericaceae), is a cosmopolitan weed that, when eaten by livestock, causes photodermatitis, reduced weight gain, and, in extreme cases, death (Giese 1980). Chrysolina hyperici (Forester) and Chrysolina quadrigemina (Suffr.) (Coleoptera: Chrysomelidae) dramatically reduced populations of H. perforatum when introduced into Australia (Clark 1953) and the United States (Holloway and Huffaker 1951; Holloway 1957). These species also have served as effective biocontrol agents when introduced into central British Columbia (Smith 1958), Ontario, and Nova Scotia (Harris and Maw 1984). This paper surveys the distribution of Chrysolina spp. in eastern Ontario, 18 years after initial release of both species.

The oribatid mite genus Zachvatkinibates, found in both littoral and forest litter habitats in North America and the Soviet Union, is redefined. Its systematic relationship to other genera in the Mycobatidae is discussed. A new species, Z. tetrasklerosis, is proposed, and Z. maritimus Shaldybina, 1973, is redescribed. Immatures of both species are described; none was previously known for the genus. Sexual dimorphism is displayed in the notogastral porose areas of adults of Z. maritimus, but not of Z. tetrasklerosis.

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

The oilseed rape crop, Brassica napus L. and B. campestris L., has undergone a significant chemical transformation during the last 15 years. Plant breeders produced cultivars with only trace levels of erucic acid in the oil compared with 40-50% in early cultivars, and with 18 μmol/g of glucosinolates or less in the oil-free meal compared with 62-1 15 μmol/g (Daun 1983). The new “Canola” cultivars were developed because erucic acid was a suspected health hazard for humans and glucosinolates caused the meal to be unpalatable or toxic to farm animals.

In a 1984 study on the ecological factors influencing the forest vegetation in the southern region of the province of Quebec (Gauthier 1985; St-Jacques 1986), an adult specimen of Cleruchus biciliatus (Ferrière) was found. This is the first record of the occurrence of the species in North America.

Sampling was done in 120 sites selected in a stratified random design in natural forests of the Mirabel area, northwest of Montreal (from 45°33' to 45°45'N and from 74°3' to 74°44'W). At each site, vegetation was sampled from an area 20 by 50 m. A 400-cm2 sample of litter was taken from each of these areas. In the laboratory, the litter samples were put into modified Berless funnels (Phillipson 1971). Following a 48-h extraction process, the organisms, collected in 70% ethyl alcohol, were identified and counted.

Adults of nine species of thrips were collected from canola fields: Aeolothrips fasciatus (L.), Anaphothrips obscurus (Müller), Frankliniella occidentalis (Perg.), Frankliniella tritici (Fitch), Limothrips denticornis Haliday, Odontothrips loti (Haliday), Thrips nr. fuscipennis Haliday, Thrips tabaci Lindeman, and Thrips vulgatissimus Haliday. Of these, F. tritici was the most abundant in the collections and appears to have the greatest potential to be a significant canola pest, followed by T. tabaci and T. vulgatissimus.

Male spruce budworm moths, Choristoneura fumiferana (Clem.), were captured in 1986 and 1987 and the proportion recently mated was determined for each sample. Mating status was examined in relation to trap location, sampling method, sampling date, and adult emergence. On a given day the proportion of recently mated males captured was similar among pheromone-baited traps both within and among test sites. The number of males trapped increased with increasing trap elevation, although there was no difference in the proportion of mated males at each elevation. Males exhibiting “mate-location behaviour” were captured individually with an insect net and were found to be mated in the same proportion as those caught in pheromone-baited traps. The proportion of recently mated males trapped tended to increase during the early part of the flight season, to fluctuate during the middle portion, and then to decline toward the end of the season. This pattern was due, in part, to adult emergence trends.

The effect of abamectin on the leafminer, Liromyza trifolii (Burgess), was investigated using topical applications, leaf dips, and repellency bioassays. Topical application of technical material in acetone to susceptible adult females provides an LD50 value of 0.404 ppm. Leaf-dip assays using abamectin formulated in water with third-instar larvae gave an LC50 value of 0.386 ppm. These data provide baseline information on the toxicity of this material to L. trifolii and are important in the development of resistance management programs. Adult female leaf miners were repelled from feeding and ovipositing on chrysanthemum plants treated with formulated abamectin up to 7 days after foliar application in choice and no-choice assays. The implications of these data in managing populations of L. trifolii are discussed.