A model of the seasonal development of Dioryctria amatella (Hulst.) is presented. The proposed biological model considers the various habitats where D. amatella is reported to occur. Cronartium fusiforme Hedge, and Hunt cankers and second-year cones of various pine species are indicated to be the main routes necessary to the development of Dioryctria amatella.

Eggs, larvae, and adults of diamondback moth, Plutella xylostella (L.), and imported cabbageworm, Artogeia rapae (L.), were monitored on cabbage, broccoli, and brussels sprouts [Brassica oleracea (L.) var. capitata, italica, and gemmifera] for 2 years in southwestern Quebec. The first eggs and adults of P. xylostella were observed during the first week of June, and the use of pheromone traps combined with plant sampling permitted detection of three to four generations on each cultivar type. However, adult counts in pheromone traps were not correlated with the number of eggs and larvae on plants. The date at which each generation appeared and their duration varied little between the three Brassica cultivars. An average of 352.7 degree-days (DD) above 7.3 °C were required to complete one generation, but the considerable overlap between generations reduced the usefulness of DD accumulations to predict P. xylostella occurrence. Visual counts of adult A. rapae and plant sampling of eggs and larvae permitted detection of three generations of this species on each cultivar type. The first A. rapae eggs were found during the last week of May, at least 2 weeks before adults were observed. However, butterfly counts were generally correlated with the number of larvae on plants. The dates at which each generation of A. rapae started were similar between cultivar types, and an average of 319.7 DD above 10.0 °C was required to complete one generation.

In view of the known lack of effectiveness and doubtful value of many of the materials cited in literature as being of value as repellents for biting flies, a series of experiments was carried out at the direction of the Dominion Entomologist, during the past three seasons, with the object of determining which of the many materials recommended as repellents might be the most effective and which the most lasting in effect.

Multiple interactions occurring within aphidophagous guilds determine their final predation outcomes, i.e., antagonistic, additive, or synergistic. Based on these predatory outcomes, the suitability of guilds in suppressing aphid pests is determined. The present study assesses the efficacy of 11 guilds, formed from both larval and adult stages of four locally abundant aphidophagous coccinellids (Coleoptera: Coccinellidae), while exploiting the pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae). The observed antagonistic effects within these guilds are resultants of enhanced predator–predator interactions due to the size and diversity of guild predators. Smaller ladybird predators maintained their usual body mass, probably by increasing their conversion efficiencies to compensate for their reduced prey consumption. However, larger ladybirds reported loss in their body mass, owing to their higher energy needs. The overall guild conversion efficiencies and growth rates were reduced. Among the experimental guilds, the observed prey mortalities were relatively higher in two-predator guilds, and within these two-predator combinations, the higher prey mortalities were recorded in those guilds where Coccinella septempunctata was one of the predators.

Diumal patterns in yellow sticky trap catch of pear psylla, Cacopsylla pyricola Foerster, are described for the spring (reproductive) winterform generation, summerforms, and the fall (diapausing/dispersing) winterform generation. For each life stage, trap catch of the two sexes is also compared, and sex ratios on sticky traps are contrasted with independent estimates of population sex ratio obtained by beat tray samples. Beat tray estimates of sex ratio showed a slight male bias for both winterform generations (although P = 0.09 for spring winterforms), and a female bias for the summerform samples. Sticky trap catches were significantly male biased for the reproductive generations (i.e. spring winterforms and summerforms). Trap catches of fall winterforms were not different from a 1:1 ratio. The male bias for the reproductive generations may be due to mate-seeking activities of males or to a decrease in activity by egg-laden females. Peak catch for summerforms occurred in the morning, and that of both winter-form generations occurred at midday. There was no evidence that trapping depleted local densities of psylla during a 24-h period.

Fifteen compounds used for suppression of lepidopteran pests of citrus were applied in a commercial manner to lemon trees. Amounts of dislodgable residues, together with mortality of Aphytis melinus DeBach confined on treated foliage, were monitored for 36 days following treatment. Most materials caused high mortalities on the 1st day following treatment. Several materials had little effect on A. melinus after 7 days post-treatment. These included a formulation of Bacillus thuringiensis Berliner endotoxin, a formulation of B. thuringiensis exotoxin, cryolite, methomyl, mevinphos, naled, parathion, and trichlorfon. Carbosulfan, chlorpyrifos, esfenvalerate, fluvalinate, methomyl, and two formulations of carbaryl caused mortality for up to 30 days post-application. Mortality in the thiodicarb treatment was above 60% for the 36 days of the study. Mortality was correlated with amounts of dislodgable residue for each material tested.

High winter mortality of eggs of three species of grasshopper occurred at various locations in Saskatchewan. Climatological factors associated with these mortalities indicated that egg survival during the winter is dependent upon snow cover as well as upon the intensity and duration of periods of subzero air temperatures.

The specific status of Neodiprion nigroscutum Middleton is firmly established by new data. The adult female is mostly black and brown. The second annulus of the lancet is generally weakly developed ventrally. The larvae have black head capsules in the first instar, but this coloration usually changes to reddish brown in the later instars. The third, fourth, and fifth feeding-instar larvae have unbroken subdorsal and supraspiracular lines, and broken postepipleural lines, but lack an epiproctal spot. The nonfeeding-instar larvae often have a pink body color. The egg mass of most females is green. Jack pine is the preferred host. The fecundity is approximately 100 eggs, but they are typically distributed over many branches, usually in one needle on each branch. Larval colonies composed of first- through fourth-instar larvae usually contain 3–10 larvae, while colonies of fifth-instar larvae usually contain 1–6 larvae. There are two generations per year in southern Wisconsin. Feeding-instar larvae are present in late May and June, and again (second generation) in August and September. The species is distributed throughout the jack pine stands of Wisconsin. Phenological data and notes on parasites are presented.

This paper offers a taxonomic arrangement of the forms of Coccinella L. that occur in the United States. Canada, and Greenland. Eighteen forms, which are arranged as 12 species, are considered to merit names. The forms of the United States and Canada were reviewed last by Dobzhansky in 1931. The arrangement proposed below differs from his as detailed in the summary that follows the taxonomic treatment. The principal difference is in the subspecies concept that is applied.

A key and measurements are presented for the eggs of 23 species of Aedes. Twenty species from California and Nevada are illustrated, and eleven previously undescribed eggs are described.

Twenty-one species of fleas, seven of which are considered true ground squirrel fleas, were collected by various means from Spermophilus richardsonii (Sabine), S. tridecemlineatus (Mitchell), and S. franklinii (Sabine) in Manitoba. Opisocrostis tuberculatus tuberculatus (Baker), O. labis (Jordan and Rothschild), Neopsylla inopina Rothschild, and Rhadinopsylla fraterna (Baker) are ground squirrel fleas reported from Manitoba for the first time. These, in addition to Oropsylla rupestris (Jordan) and Thrassis bacchi bacchi (Rothschild), were restricted to the southwestern region of the province, but Opisocrostis bruneri (Baker) was collected throughout the range of the ground squirrels, irrespective of location. Fourteen species collected were considered accidental on ground squirrels, one of which, Tamiophila grandis (Rothschild) (an eastern chipmunk parasite), was recorded for the first time in the province.

Spring-felled logs of Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco, and western hemlock, Tsuga heterophylla (Raf.) Sarg., were attacked by ambrosia beetles, Trypodendron lineatum (Oliv.), in the year after felling. By monitoring individual galleries it was determined that brood production was similar to that found in fall- and winter-felled logs. The sex ratio of the brood did not differ significantly from 1:1. Only beetles that had failed to establish successful galleries emerged during the "second" flight period. Significant linear relationships were found between frass weight and each of the following variables: number of egg niches, emerged adult progeny, and gallery length. Mortality in galleries in Douglas-fir and western hemlock logs, respectively, was found to be 9.4 and 12.4% between the egg and larval–pupal stage and 19.5 and 32.1% between the larval–pupal and adult stages.

Nymphs of lotic mayflies live in environments that are expected to give rise to different degrees of population structuring. Here we investigate two taxa adapted to different lifestyles. Baetis macani Kimmins (Ephemeroptera: Baetidae) lives in flowing water; brooks that may periodically dry out in the summer or freeze to the bottom in winter. Baetis jaervii Savolainen is mostly found in sedge belts along the shores of lakes. Most insects living in flowing water show low levels of among-population genetic differentiation within and among catchments. Levels of differentiation in the lotic species are therefore assumed to be lower than in lentic B. jaervii. Here we test this hypothesis. Mitochondrial DNA and allele frequencies of nuclear genes were used to detect population structure in specimens originating from an extensive area from northern Finland. The genetic differentiation among populations of the lotic B. macani is more than twice the corresponding value for the lentic B. jaervii (FST 0.33 versus 0.15, while the mean FST between species was 0.33 and significant). The result is congruent within the cytochrome c oxidase subunit I gene (COI) partial gene frequencies. We argue that the significant genetic population structure, which only was found in the lotic B. macani, is differentiated as a consequence to the unpredictable environment as contrasted to the stable environment in standing bodies of water.

Bryophaenocladius brincki (Freem.) comb, nov., B. productus (Freem.) comb, nov., B. laticaudus spec, nov., and B. digitatus spec. nov. are described or redescribed.

The new genus Tokunagaia is given for Adactylocladius Sæther 1969 pro parte, nec Sæther 1968. A new name, Orthocladius (s. str.) curtiseta, is given for O. brevisela Sæth. nec Kieff. Some new synonyms and records are given.

The seasonal history of the grape phylloxera, Phylloxera vitifoliae (Fitch), infesting vine roots in commercial vineyards in the Niagara Peninsula, Ontario, was investigated from 1960 to 1963, mostly on the variety Delaware. Galls caused by the phylloxera feeding on actively-growing feeder rootlets first appeared about mid-June, and increased to a maximum in late August or early September. Numbers of phylloxerae on the infested roots increased during the season until hibernation. Nymphs of the winged form of phylloxera were first found on the roots on dates ranging from 16 July to 22 August, and continued to occur for 11/2 to 21/2 months. Hibernation usually began in the latter part of September, and reached 90% between 2 and 23 October. Usually fewer than 10% of the hibernants survived the winter.

There were more infested vines, more galled roots, and relatively more phylloxerae in vineyards on clay loam soil than in sandy loam.

Hibernants resumed activity in the laboratory in a few days at room temperatures, and became adults in as little as 10 days.

Cylindrical traps with screen cones at the ends baited with virgin females and placed in rape fields about 1 m above ground level were effective in trapping males of the bertha armyworm. Males were most active between 0330 and 0430 h M.D.T. and moved precisely to confined females. Virgin females became attractive 1 day after emergence and remained attractive for at least 7 days. Trapping was an effective method for rapidly determining the presence of bertha armyworm.

Banchus flavescens Cresson is the most abundant hymenopterous parasitoid of the bertha armyworm, Mamestra configurata Walker, in western Canada. The females attack 1st, 2nd, and 3rd instars of the host. The speed of parasitoid development is adjusted so that the 2nd instar is completed when the host finishes feeding. Banchus flavescens has an obligate diapause and overwinters as a prepupa within a cocoon in the soil. Notes on life history and descriptions of the egg and 5 larval instars of B. flavescens are given.

Medetera aldrichii Wheeler larvae enter galleries of Dendroctonus ponderosae Hopkins through the beetle entrance holes. Observed larval densities of the fly were greatest in the May–June period following beetle attack. Densities were consistently greatest in the portion of the tree 5–10 ft aboveground; averaging around 3–4/sq. ft. The fly larvae probably cause a major share of the beetle mortality between August and the following May. The fly larvae pupate near beetle-created openings that lead from the galleries to the exterior.

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 sawfly Neodiprion swainei Midd. has long been recognized as a serious defoliator of jack pine, Pinus banksiana Lamb., but it was not until the relatively recent use of jack pine as a raw material for pulp that interest in the sawfly became acute. Subsequently, investigations into the natural control of N. swainei were begun in the year 1955 near the headwaters of the Gatineau River, P.Q. (47° 55′ N., 75° 25′ W.) which was considered to be near the centre of the current infestation.