In 1966–67, the following fungi were isolated on Adelges piceae (Ratz.), a serious pest on fir trees in the Gaspé Peninsula: Fusarium larvarum, Cephalosporium coccorum, Entomophthora sp., Aspergillus fumigatus, Aspergillus nigra, Penicillium thomii, Penicillium sp., Cladosporium sp., Isaria farinosa, and Beauveria sp. F. larvarum showed more evidence of pathogenicity for Adelges, while C. coccorum was considered a facultative pathogen. There were not enough cases of infection by Isaria, Beauveria, and Entomophthora to determine their activity. Remaining species were saprophytic. Pathogenicity tests were conducted in the field with F. larvarum and C. coccorum. The fungi were introduced in the population by spraying or dusting, or by mites. However, a variety of external factors made it impossible to determine accurately the degree of virulence of these fungi for Adelges.

The balsam woolly aphid was introduced over 60 years ago from Europe into the Maritime Provinces of Canada where it established on Abies balsamea (L.) Mill. Ecological characteristics of the insect that are important to the survival and spread of populations in the new environment are feeding habits, cold-hardiness, and dispersal capacity. The aphid feeds on the bark cortex of all parts of the tree from the stem to the crown. ’Stem attack’ refers to the population established on the main stem while ’twig attack’ refers to the population established in the crown where the aphid may settle on numerous sites but mainly at the base of young shoots. Freezing is fatal and the probability of freezing increases as temperatures fall below −5°F. There are no survivors at −35°F no matter how brief the exposure. The adults are wingless and populations are spread mainly through wind dispersal of crawlers and eggs.The climate of the Maritime Provinces changes markedly from the coast inland from maritime, through transitional, to continental. Infestations in maritime and continental climatic regions follow particular patterns while in the transitional region the course of infestation is irregular. Climate is unimportant in determining population trend in maritime climatic regions. The probability of experiencing temperatures below −15°F in a winter is 0.10 and populations survive on the stem and in the crown. Crown populations are dispersed freely and the aphid and aphid damage is general. In the continental climatic region, the probability of −30°F occurring in a winter is 0.46 and populations are restricted to the base of the tree where snow cover provides protection. Wind velocities below the canopy are light and infestations remain isolated and small with damage from stem attack accumulating at a slow rate. In the transitional climatic region, the severity of winter is irregular with periols of mild winters being broken by occasional extremely cold winters. Tree mortality from twig and stem attack has been heavy in some stands while infestations in adjacent and equally susceptible stands have been arrested by severe winters.

This species is a member of the Delininae whose species with known life histories all attack plants belonging to the Liliaceae and Orchidaceae. Eggs are laid singly or in groups of up to 15 eggs on the abaxial surface of Veratrum viride leaves. Larvae produce extensive blotch mines as they feed upon the mesophyll layer. Puparia are formed in the soil, and the pupa is the overwintering stage of this univoltine species. A table outlining larval attributes of the Scatophaginae and Delininae is given.

A colony of Leptocera caenosa (R.) was self-sustaining for 60 generations in a variety of organically rich media. With a wet larval medium of green grass meal and expanded mica in equal volumes at 17 °C the life cycle was completed (female to female) in an average of 31 days (egg stage, 2 days; larval and pupal periods, 13 days each). Green grass meal was superior to a standard cereal house-fly medium (CSMA) and legume leaf meals; a low coumarin strain of sweet clover was superior to a high coumarin strain. A non-sterile nutrient solution was also successfully used. In one sample of fresh alfalfa meal the pupal period was about 2.5 times longer than that in grass meal, possibly because of the presence of an estrogenic hormone.The species survived a 3-month exposure to 7 °C but not 1.5 °C, indicating that it could not readily survive out-of-doors during the winter in Saskatchewan.

Experiments with rutabagas, cabbage, and cauliflower were conducted on mineral soils, mainly with pre plan tin g soil treatments of insecticides applied in bands placed about 2.5 cm below the soil surface (1.25 cm below the seed) in shallow ridges to determine the best insecticides for use in controlling the cabbage maggot. Drench or granular spot applications were also used for transplanted stem crucifers. Broadcast, surface band, and supplementary drench treatments had been tested earlier but were discarded in favor of the band-in-row treatments, mainly because of hazard to beneficial predators and parasites. Of the many materials tested, carbofuran, fensulfothion, and chlorfenvinphos have consistently given the best control throughout the growing season. Trichloronat, E.I. 47031, and mecarbam also gave good results. Thionazin and phorate gave excellent control until 1968 when applied at the exact required depth in the row with machinery; control was often erratic when these materials were applied on a field scale with hand applicators. In 1968, these two insecticides gave less effective early season control and poorer residual control than in previous years. Carbofuran, and phorate, appeared to influence the development of rhizoctonia rot lesions on the sides of the roots more than other materials in all experiments. Rot lesions were more numerous and severe on rutabagas that followed potatoes than on land that had previously been used for cereals. Root maggots in stem crucifers were controlled with a number of insecticides. Methods of application for all cruciferous crops are discussed.

Cohort life tables are seen to provide the basis for an analytic and insightful approach to the rational management of crop pests. A life table is presented for a typical planting of early market cabbage, and dx values appraised in the light of potential dollar revenues.

Larvae of Enoclerus sphegeus Fabricius (Coleoptera: Cleridae) were separated into three groups for study. Throughout their development, the larvae in each group were fed mountain pine beetle larvae, Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae), of a specific size (small, medium, or large). Clerid larvae fed small D. ponderosae larvae generally completed three stadia, while the other two groups, which were fed medium-sized and large prey, respectively, usually passed through two larval stadia. The number of stadia a larva would have was determined by the amount of food consumed during the first stadium. The feeding period of larvae given small prey was considerably longer than that of those fed medium-sized or large beetle larvae, but the prepupal period was much shorter. The head capsules of second-instar larvae that passed through two stadia were distinctly wider than those of second-instar larvae that completed three stadia.

Studies on non-treated plots at Harrow, Ontario, in 1967 and 1968 and at Kentville, Nova Scotia, from 1963 to 1968 inclusive showed that residues of viruses of the cabbage looper, Trichoplusia ni (Hübner), found in soil were related qualitatively and quantitatively to the virus residues on leaves of cruciferous plants grown in the plots and to mortality by viruses in the host populations. At Harrow where the cabbage looper is common and where virus diseases occur naturally in field populations, the viruses that occurred in the populations of the host built up in soil as the season progressed. At Kentville where the host is rare, virus was rarely found in soil or on foliage. The typical nuclear-polyhedrosis virus, an atypical nuclear-polyhedrosis virus that formed abnormally large polyhedra, and a granulosis virus were found at Harrow, with the typical nuclear-polyhedrosis virus predominating. Only the typical nuclear-polyhedrosis virus was detected at Kentville.

The two primary functional response models extant in recent entomological literature were compared using a common set of data. Use of an iterative least squares parameter estimation routine was shown to be essential to a comparison of these two models. With parameters properly determined, the Watt model fit data on one out of five experiment days best, the Holling model fit data best on four out of five experiment days. The "handling time" submodel was shown to require iterative least squares parameter estimation rather than the usual log transformation and subsequent fitting of this logistic function by standard linear regression techniques. The conclusion was reached that if accuracy in prediction by nonlinear functional response models is desired, proper methods of determining parameter values are of critical importance.

High fecundity from Chrysopa carnea was obtained from an inexpensive diet containing a commercially available product of dried, inactive Saccharomyces fragilis yeast and whey proteins. The effective diet consists of this product mixed with sucrose and water. S. fragilis autolysed 17 hours was more effective in diets than when autolysed for 36 hours or unautolysed, and was as effective as autolysed brewers’ yeast, S. cerevisiae.

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.

A rod-shaped noninclusion virus infects the European red mite, Panonychus ulmi (Koch), in Ontario. Infection and death can occur in any postovarial stage. Most infected mites contain, in the midgut, more or less spheroidal inclusions with a radiating crystalline structure. Infected mites deposit inoculum on the leaves, probably in excreta or oral secretions at feeding sites, which is picked up orally by uninfected mites while feeding. The inoculum on the leaves is very unstable, seldom remaining infective for more than a week and being almost immediately inactivated after exposure to water. Suspensions of infected mites, triturated in water or various solutions, were inefficient inocula.Introduction of virus into orchard populations of P. ulmi induced epizootics that rapidly reduced the population density. Natural epizootics were found only in dense populations.

The genus Cuerna Melichar as represented in Canada is reviewed. Cuerna costalis (Fabr.) is recorded for the first time. Seven new species of Cuerna are described from the Prairie Provinces and British Columbia: cuesta, fenestella, inflata, nielsoni, pseudoalba, reducta, and xyla. The identities of C. striata (Walker), C. lugens (Walker), and C. septentrionalis (Walker) are determined. All the species are described and illustrated, and a key is provided to the species-groups and species from Canada.

Basilia astochia new species is described from Colombia, from Vampyrops helleri Peters. It is closely related to B. ferrisi Sch. Stekh. and B. speiseri (Mir. Ribeiro) from which it differs in details of the shape and chaetotaxy of the legs, tergal plates, and sternites. These three species probably form a very closely linked "Artenkreis" occurring from Guatemala to Brazil, Paraguay, and Peru.

Scolytus ventralis females attack their host, Abies grandis, at random in the beginning of the flight period. The success of these attacks, as manifested by the length of the gallery, is determined by the rapidity of the host’s resinous response, attacking females being repelled by resin flow. Aggregation occurs on both resistant and susceptible hosts but is directly associated with the degree of gallery elongation. Resinosis occurring after brood establishment reduces survival, having its greatest impact on the early developmental stages. Mortality from resinosis is inversely related to attack density.

A telemetric system for the measurement of bark temperature of standing trees was developed and compared with a conventional thermocouple system. The components of the system and circuit diagrams are given. The cost of a single unit was about $65. The system was field-tested under both summer and winter conditions in the Sierra Nevada mountains of California. It was concluded that the telemetry system gave more accurate temperature readings and that it possessed several other advantages over the conventional system. While the system was developed for the measurement of temperature, it could be used for the measurement of any environmental variable for which there is a variable-resistance transducer.

Fifty-seven species of 27 families of mites associated with apple trees in Annapolis Valley, Nova Scotia, were recorded. Five species were phytophagous, 34 species were presumably predacious, and 18 species were presumably scavengers and fungus feeders.

An efficient oviposition cage for the codling moth, Carpocapsa pomonella (L.), is described and illustrated by photographs and line drawings. Essentially, the cage is a revolving drum with waxed paper walls (the oviposition surface) and wire screen ends. Use of this cage achieves satisfactory egg yield per female moth, uniform egg distribution, and easy and quick replacement of the oviposition surface without handling the moths.

Poecilips pteridophytae Schedl is the first species of Scolytidae to be found on a fern. It appears to be fairly widely distributed in New Guinea on the tropical bracken fern, Pteridium aquilnum (L.). The association is most probably of recent evolutionary origin. The immature stages are described in the text. Its life history is relatively short, the life cycle raking 2 to 4 mouths, and takes place wholly width the stem of the fern, except for emigrating adults. P. pteridophytae may have considerable economic potential as a biological control agent of bracken fern in countries where it is a pest.

Water deposited on peach leaves as a constantly replenished film for 48 hr killed few European red mites, Panonychus ulmi (Koch), by drowning. Considerably more, especially of larvae, were lost by their coming loose from the water-covered leaf surface and floating off; the proportion thus lost did not differ greatly between 6- and 48-hr treatments. Relative humidity of 100% and to a lesser degree, 96–99%, inhibited activity and development.