A common regression equation, representing data collected from four widely separated areas, was constructed to determine number of eggs of the Douglas-fir tussock moth based on individual egg mass weights. The regression is designed for use in any egg mass sampling scheme where a knowledge of the potential early instar population is required. The regression equation is also given for each area.

A plot of 6 m tall white spruce trees was treated with an aerial application of an oil-base spray containing a non-toxic compound, Tris (2 ethyl hexyl) phosphate (referred to as TOF), which was amenable to gas-liquid chromatographic analysis The spray was formulated and applied at a rate to approximate the eastern Canadian operational spruce budworm control sprays. Meteorological measurements were made in the airspace from mid-crown height to the height of spray emission for the period of spray application and deposition. Spray deposit collection units (kromekote cards and glass plates) were used to record spray deposit at ground level.

Foliage samples and complete branches were taken from each of three trees at a series of heights and each of the four compass quadrants and returned to the laboratory for chemical analysis. Spray deposit was determined in terms of ppm TOF on the foliage. The kromekote cards provided information from which the drop size characteristics of the spray cloud and the deposit in terms of drops/cmK were determined; a colorimetric analysis of spray deposit on the glass plates indicated the volume of spray deposited.

Analysis of the spray deposits on the foliage indicated gradients in deposits with most on the upper, outer, upwind portions of the trees and least on the lower, inner, downwind portions. These differences were significant. These gradients can be attributed to two weather factors (a) the prevailing wind drifting the pesticide cloud through the forest canopy resulting in a filtering to produce a decreasing gradient from upwind to downwind side of the tree, and (b) air eddies around the tree tops resulting in an increased deposit and slight penetration of the spray cloud on the outer downwind portions of the tree.

This study demonstrates that a finely atomized spray applied to a white spruce forest under suitable weather conditions will give a deposit on the outer portions of the tree with a variation of only about 50% in spray deposit but with significantly less deposit on the inner, lower portions of the tree.

The sunflower moth, Homoeosoma electellum (Hulst) is a constant and damaging pest of cultivated sunflowers in Texas, Nebraska, and California. It was reported in Canada from Manitoba and Saskatchewan as early as 1936. Present studies begun in 1975 show that it can cause economic damage to cultivated fields in Saskatchewan. Field observations also indicate that this pest does not overwinter in Canada but that adults fly, or are blown in, from the south each year.

An efficient method of rearing this pest in the laboratory was developed and observations on its life history and behaviour, especially courtship and mating behaviour, are reported herein.

The within crown distribution of three species of Pleroneura and their food source (active buds) was determined on white fir trees 5–30 ft tall. Over 90% of all active buds and 94% of all infested buds occur in the outer half of the crown. Over 50% of the total active and infested buds occur in the middle third of the crown. Percentage infestation within the crown increases from bottom to top. Percentage infestation per tree decreases as tree size increases.

Glaucosarcophaga knabi Townsend is a synonym of T. albicans (Wiedemann), a highly variable species; a comparative study of specimens from South America and Mexico was made.

The 11 genera of Nearctic Braconini are keyed: two of them, Myosoma Brullé with a wide pantropical range and Alienoclypeus Shenefelt, new genus, are found chiefly in the Chihuahuan desert and shrub fauna of northern Mexico and the southwestern U.S.A. and are recorded as Nearctic for the first time. Four new species are described in Myosoma: eumystax, impexum, longius, and durango. R. D. Shenefelt describes a new genus and species, Alienoclypeus insolitus. The genus Atanycolimorpha Viereck, 1913 is synonymized with Ipobracon Thomson, 1892. The genus Coeloides is revised for the Nearctic Region; 12 species are described and illustrated. Five of these are new: mexicanus, durangensis, sympitys, tsugatorus, and sonora. One species, C. rossicus (Kokujev), is Holarctic, a new subspecies, betulae, is described from Canada. The following are new synonyms: C. rufovariegatus (Provancher) = (dendroctoni Cushman), C. vancouverensis (Dalla Torre) = (brunneri Viereck), C. crocator (Kirby) = (promontorii Dalla Torre).

A new trapping technique which selectively captures Culex sp. mosquitoes during oviposition is described. A comparison of this trap to CDC and CO2 traps is presented and the advantages of the oviposition trap for viral monitoring discussed.

Four commercial sex attractant traps were evaluated for monitoring low density spruce budworm (Choristoneura fumiferana (Clem.)) populations. Factors considered were color, the number of male budworm caught, durability of traps and their ability to exclude non-target insects and debris. The Pherocon 1CP was superior to 3-M Brand Sectar 1 and XC-26; Pherocon 1C was least suitable. Interpretation of the numbers captured may be confounded by the fact that trapped males repel other males.

In order to establish a functional relationship between damaged pine tips apparently infested with Nantucket pine tip moth, Rhyacionia frustrana (Comstock), and within-tip larval and pupal population, X-ray techniques were used to determine numbers of actually infested tips and the numbers of tip moth immatures contained therein. Linear relationships existed between these variables and changes in tip moth density. The effect of different plantations, tip moth generations, season, and tree age did not significantly alter the observed relationships. Approximately 40% of the damaged (i.e. apparently infested) tips were actually infested, and these tips contained an average of 1.4 tip moth immatures per tip. The equation Y = −.509 +.57X estimates the number of tip moth immatures, given the number of apparently damaged tips per tree (r2 =.71).

A total of 34 species of female tabanids were collected with CO2-traps from four different habitats near Guelph, Ont., during the 1971, 1972, and 1973 fly seasons. Nearly equal numbers of species were trapped at the Ontario Reformatory, Preston, Kortright, and the Hanlon Creek watershed, comprising a total of 15 Chrysops spp., 12 Hybomitra spp., 6 Tabanus spp., and 1 Atylotus sp. Relative abundance and flight periods are reported for each species. Chrysops frigidus O. S. and Hybomitra lasiophthalma (Macq.) were the most abundant species among their respective tribes; their abundance was related directly to degree of soil wetness, differing from that of Tabanus similis Macq. and T. quinquevittatus Wd. which was related inversely to these habitat types. The flight period of nearly 85% of the sampled population, consisting mainly of C. frigidus, H. lasiophthalma, and H. epistates (O.S.), spanned from the end of May till mid-July. T. quinquevittatus, T. lineola Fab., and H. epistates occurred till mid-September.

Due to concern over an outbreak of bluetongue disease in cattle near Osoyoos, B.C., a survey of Culicoides spp. was made and the seasonal and immediate geographical distribution of the known large-mammal biting species studied. Species found included C. cockerelli (Coquillett),C. crepuscularis Malloch, C. near haematopotus, C. jamesi Fox, C. montanus Wirth and Blanton, C. obsoletus (Meigen), C. occidentalis Wirth and Jones, C. palmerae James, C. piliferus group, C. travisi group, C. variipennis (Coquillett), C. yukonensis Hoffman, and Leptoconops kerteszi Keiffer. The active period for adults of C. occidentalis, a proved vector of bluetongue disease, is from mid-April through early October. Breeding sites of this species were common from 275 to 600 m above sea level throughout the area of bluetongue disease incidence. Breeding sites extended up to 1350 m and adults were trapped at 1820 m. A large number of adult C. occidentalis and other Culicoides spp. were collected for isolation of bluetongue virus. No virus was recovered. This was possibly due to large-scale testing of susceptible domestic animals for bluetongue virus antigens and removal of those giving positive reactions prior to collection of the insects tested.

The “cyclostome” subdivision of the Family Braconidae was recognized by Wesmael in 1835 and characterized as having the clypeus emarginated in such a way that a circular opening is left between it and the mandibles. This character has been used as one of the bases for primary segregation of the family into major groups ever since. However, it has long been recognized that other features are involved. For example, the clypeus is not simply emarginate but is also raised or becomes carinate transversely (horizontally) across the middle and it is the portion of the clypeus ventrad of the ridge which is impressed in such a way that the clypeus appears to be cut out. The degree to which the clypeus is infolded (backfolded) varies considerably. In addition, the labrum, which is broad at the base and narrows to the apex, is concave on the anterior side. This concavity is useful in segregating groups such as the Opiinae from the cyclostomes. Authors have tended to retain the cyclostome group as the subfamily Braconinae in the broad sense and to include therein the Rogadinae and Doryctinae.

The formation of a yellow band inside the stalk of each ovariole was a good indicator that a female European corn borer had laid eggs. The absence of these bands was less reliable as an indicator that no eggs had been laid, probably due to the time taken for the bands to form. The numbers of moths accumulating in a light trap over a week at Harrow, Ontario, and the numbers of females estimated to have laid eggs correlated significantly with the numbers of larvae developing in nearby green pepper plots 3, 4, and 5 weeks later during second generation flights. This enabled linear equations for forecasting pepper damage to be developed, in which the dissection data was more useful than the total moth catch alone.

Aerially sprayed fenitrothion (0.21 kg/ha) caused mortalities from 100% among experimentally caged bees in exposed habitats to 47% in cages placed under dense forest canopy. Bumble bees found foraging in sprayed areas during the days immediately following the spray suffered significantly higher subsequent mortality than those in unsprayed areas.

Long-term effects were investigated by comparing late summer Bombus population densities among sites representing various spray histories. For all species combined, abundances in unsprayed areas averaged 3 times higher than in fenitrothion treated areas. Population recovery appeared to be complete within a few years after discontinuation of spraying.

Foraging performance by laboratory reared colonies was significantly higher in sprayed areas with reduced bee populations than in a control area, possibly because of relaxation of competitive stress. The diversity of plant species used for pollen collection was nearly twice as great in the control as compared with sprayed areas, suggesting that the effect of fenitrothion spraying on cross-pollination may be greatest for plants which are subdominant in the hierarchy of bee preference In one such plant, red clover, reduced seed-set was demonstrated.

Nesting materials for use by the alfalfa leafcutter bee (Megachile pacifica Panzer) were compared. When all experimental designs were combined, the leafcutter bees nesting in grooved solid woods, such as pine and fir plywood, and in the polymers, styrofoam and polystyrene, produced a greater percentage of viable cells (i.e., cocoons) than those nesting in drilled boards, soda straws, K3 particle board, aluminum, or corrugated paper. Pine and polystyrene are the only nesting materials now used commercially in Western Canada and chalcidoid parasites occur in low numbers in them because the hives are made precisely. Cells can be mechanically removed from laminated grooved nesting boards so that a loose-cell system of bee management is feasible. Although more expensive initially, these boards are competitive with other nesting materials as they can be reused.

Southern pine beetles (Dendroctonus frontalis) carrying phoretic Trichouropoda australis deutonymphs were caught in bucket traps baited with frontalin-alpha pinene at heights of 3, 6, and 9 m on the boles of loblolly pines. Of 8475 beetles collected, 36.3% carried uropodids or their pedicels. Beetles trapped at 3 m carried more pedicels than those trapped at 6 or 9 m, indicating that the flight of beetles is influenced by the presence of phoretic mites. Re-emerging parent beetles can be differentiated from brood adults by the color of the mite pedicels.

The bioactivity and disappearance of chlorpyrifos in Dursban® 2.5 G and M formulations was studied in the laboratory and in the field in temporary pools lined with sod, clay, or sand substrate. The activity and presence of chlorpyrifos in the water was determined by bioassay with Culex tarsalis Coquillett larvae and chemical analysis by gas-liquid chromatography.

The tests indicated that, at equal rates of application in pools with organic matter or clay substrate, the 2.5 G formulation resulted in lower chlorpyrifos concentrations than the Dursban M, but provided periods of larval mortality equal to or greater than the M formulation except in laboratory sod-lined pools. At a given application, the shortest period of larval mortality and lowest detectable residues occurred in sod-lined pools, whereas in the sand-lined pools, the longest period of larval control and the highest residual concentration of chlorpyrifos in the water was encountered.

The wing-morph composition of populations of planthoppers exploiting stable and temporally uncertain resources was determined. In stable habitats like salt and fresh water marshes, the optimum population strategy of most planthoppers is to produce flightless brachypters which can efficiently use and remain on the immediate resource. Macropters, which can fly, are more adaptive and predominate in temporary habitats because they can emigrate and colonize new resources when conditions are no longer suitable.

Several streams near Baie Comeau, Quebec were treated with a particulate formulation of methoxychlor (particle size 8–15 μ) or Abate® (particle size 2.5–20 μ) at a dosage of 0.1 ppm for 15 min to determine if such a formulation is effective against and selective for black fly larvae. The effects of these larvicides were evaluated by sampling the stream fauna before and after treatment with cones, Surber samplers, drift nets, and rock sampling. A new caging device, the entrapment sampler, was used to assess mortality directly.

Both larvicides were effective against Simuliidae. Neither particulate insecticide was completely selective for black fly larvae, since philopotamid larvae and some chironomid larvae were also killed. Although some other detritus-feeding insects also were affected, numerous families of insects including potential predators of Simuliidae were not affected appreciably by these particulate larvicides. Particulate Abate affected a few more families of insects than particulate methoxychlor. The comparative effects of these formulations and the corresponding liquid formulations on stream fauna are discussed. Particulate formulations are a promising alternative to the present formulations used for black fly larviciding, and further research on their safety and performance and on methods of aerial application is recommended.

A study was made of the reason for the fairly rapid loss of attractancy of pheromone traps for the European corn borer, Ostrinia nubilalis (Hübner). This loss in attractancy appeared to be attributable mainly to formation of an inhibitory or repellent substance(s). Although traps with a suspended pheromone dispenser were significantly more attractive than traps with the dispenser placed in contact with the adhesive, they still became relatively unattractive to male corn borers within approximately 1 week.