In New Jersey, Typhlodromus pomi (Parrott) was the only predacious phytoseiid mite on most non-sprayed apple and deciduous trees. It also became the most numerous phytoseiid mite recolonizing apple trees a year after toxic spray residues had dissipated. Amblyseius fallacis (Garman) was the first phytoseiid mite collected from apple trees following cessation of toxic sprays and was usually abundant at the time of large red mite populations; later, an influx of several different species occurred. A. fallacis was the most common phytoseiid mite on low growing plants and was able to tolerate higher residues of toxic materials than other species. Other phytoseiids taken from sprayed apple trees in order of abundance included A. driggeri n. sp., A. amicus (Chant), T. longipilus Nesbitt, T. conspicuus (Garman), T. mexicanus (Garman), T. caudiglans Schuster, and A. pepperi sp. n. Species other than T. pomi found on non-sprayed apple trees were A. finlandicus (Oudemans), T. longipilus, T. caudiglans, and T. conspicuus. None of these species was entirely confined to apple. Five other species were collected that were not found on apple: T. flumenis Chant, T. pyri Scheuten, A. elongatus (Garman), A. okanagensis (Chant), and A. picketti sp. n. Three species collected from greenhouse plants in association with tetranychid mites were: A. fallacis, T. longipilus, and A. picketti.

Three new species of Amblyseius are described. Two undescribed males and the spermathecae of the females are illustrated.

The innervation of a pregenital, the genital, and postgenital segments of the male and female of Schistocerca gregaria (Forskäl) is described in detail and is compared with other orders of the Insecta.

Seven species of Braconidae from southern Canada are described: Colastes polypori and Meteorus betulini from annual bracket fungus Polyporus betulini on birch, Diospilus fomitis from the perennial bracket fungus Fomes fomentarius on birch, and from Dorcatoma dresdensis (Anobiidae) in Ganoderma applanatum, Ichneutes pikonematis from Pikonema alaskensis, Cantharoctonus canadensis from Bucculatrix canadensisella, Hormius tsugae from Pulicalvaria apicitripunctella on hemlock and P. piceaella on spruce, and Microctonus loani from adults of Altica corni, Altica ambiens alni, and Calligrapha philadelphica.

Using bioclimatic chambers to provide diurnally fluctuating temperature and humidity conditions, the relationship between fecundity of females of the aphid parasite, Praon exsoletum (Nees), and different host densities, was examined over a wide range of mean temperatures. At each temperature level the number of eggs laid by females was found to vary with host density in accordance with the functional response curve (disc equation) of Holling. Superparasitism was common at all temperature levels studied, and, irrespective of host density, eggs were found laid at random with respect to hosts present. The functional response equation was thus modified so that number of hosts attacked was determined by both number of hosts present and number of eggs laid. Using this modified disc equation, the bioclimatic characteristics of parasite oviposition were examined from rhc standpoint of varying temperature levels. Oviposition was limited to mean temperatures between 8° and 29°C; near these limits the maximum number of eggs laid and the maximum number of hosts attacked were low. At medial mean temperatures (13°–24°) the number of eggs laid per parasite was high, averaging between 70 and 110 each 12-hour day. At these same medial temperatures, according to the modified disc equation, the average "handling" time per oviposition attack was shortest, and the parasite effective searching rate fastest. Averaged over a 12-hour day (this parasite does not oviposit in darkness), females of P. exsoletum were capable of laying from seven to nine eggs per hour at temperatures between 15° and 24° respectively. In all cases, the number of hosts attacked varied with numbers of eggs laid in accordance with Thompson’s superparasitism formula.

Bucculatrix canadensisella Chambers, an important defoliator of birch trees in Canada, overwinters as a cocoon in forest-floor debris. Cocoons obtained from the field over a 3-year period showed that high mortality attributable to climatic conditions could occur during this stage. Field and laboratory experiments indicated that cocoons were quite resistant to various conditions of moisture and to cold in the fall and through the winter, but that they were highly susceptible to dry conditions at the time of morphogenesis in the spring. Cool temperatures retarded adult emergence; in nature, this would expose cocoons to a prolonged period of predation. It is concluded that weather conditions during a critical period of a few weeks in late spring could greatly affect cocoon survival of this insect. Warm, moist weather would offer optimum conditions while cool and (or) dry weather would result in high mortality.

Choristoneura houstonana (Grote) lays eggs singly in July. Egg development ranged from 8 to 11 days, with the majority hatching 10 days after oviposition.

Larvae are solitary, and mine during early instars but later instars feed externally on leaves in shelters made by webbing foliage together. There is one generation each year and overwintering occurs in a hibernaculum, in mined leaves. Field-collected head-capsule width frequencies indicated nine larval instars. Rearing larvae on seedling junipers indoors indicated a range of 8–11 instars.

Pupation occurs during June and July in the shelter where the larva feeds. The pupal stage lasted about 10 days at a constant temperature of 80°F.

A machine is described which generates a standard, mosquito-attracting “target” to which controlled additions of various volatile chemicals can be made and the amount needed to repel the insects thereby measured in micromoles per liter of air. The apparatus can be used with both solids and liquids as well as with blends or mixtures. While principally intended for testing mosquito repellents, it can probably be adapted for use with other biting insects and ticks.

Field studies were carried out on effect of attack by unmated spruce beetles, Dendroctonus obesus (Mann.) on log attractiveness. Test logs were screen-covered or sprayed with insecticide. Trays beneath logs, with glass-barrier traps beside them, were used to measure response of beetles from natural populations.

About 89% of the beetles attracted at six replicate sites were taken at logs containing introduced females. Males always predominated in responses to these logs. After the initial flight, about equal numbers of each sex responded to logs without introduced females. Response to the latter dropped to a low level after the initial flight, but beetles continued to respond well to logs attacked by females throughout the flight period. Use of increased attractiveness to logs following introduction of female beetles shows promise as a means of studying, directing, or controlling infestations of the spruce beetle.

Dicofol was applied to bean leaf discs in various ways. The number of drops per disc, the concentration of dicofol in each drop, and the size of the drops were related to egg laying and mortality of adult female mites placed on the discs. Under the conditions of the experiment, an increase in concentration above normal field strength (0.046% active ingredient) had little effect, even though the deposits were discontinuous and similar to those expected from low-volume spraying. Repellency of dicofol to mites was reaffirmed and toxicity effects were significant when about one-quarter of the leaf surface was covered by deposit.

The debris-feeding insects Trogoderma glabrum (Hbst.), Tribolium madens Charp., Cryptolestes ferrugineus (Steph.), and Vitula edmandsae Pack, were controlled by cleaning out die nests of Megachile rotundata L. annually and screening off the debris, and by discarding the cells of M. rotundata after emergence was complete. The chalcidoid parasites Monodontomerus obscurus Westw. and Pteromalus venustus Wlkr. and the depredators Coelioxys spp., were removed by light-trapping them in the incubators in which M. rotundata was being hatched. The removal was made possible because the incubation period of each of the indigenous enemies was considerably shorter than that of their exotic host.