Cocoons of the larch sawfly normally spend from nine to ten months in the ground per annum under conditions existing in western Canada. For this reason biotic and abiotic soil factors are of paramount importance in the epidemiology of this insect. Preliminary observations and experiments indicate that ground water is one of the most important of these factors in that it not only affects sawfly development directly but also is significant in regulating sawfly predators and possibly parasites.

Recent developments in the insecticide field have made available to the economic entomologist a wide variety of chemical compounds which exhibit high toxicity to certain species or groups of insects. The pyrethrins rotenone and nicotine, reinforced by the dinitro compounds and thiocyanates of prewar times, have now been joined by the chlorinated aromatic hydro-carbons: DDT, gammexane, chlordane and toxapohene.

In the course ot laboratory tests with insecticides, some interesting data were obtained relative to the effect of certain materials upon the over-wintering egg masses of the Eastern tent caterpillar. The data appear to be of sufficient interest to warrant further study and are presented here with that purpose in mind.

A number of egg masses was collected. These were brought into the laboratory, were examined and sorted into lots roughly comparable in numbers. The twigs to be sprayed were segregated. Solutions of the following insecticides were then prepared.

The meteorological program of the Sault Ste. Marie Forest Insect Laborarory was inauguraced during 1946, with the establishment of stations at Sault Ste. Marie and Black Sturgeon Lake, for the study of the spruce budworm,Choristoneura fumiferana (Clem.) (vide Freeman, 1947) as its first subject. During 1946 and 1947, joint field and laboratory studies have been concerned primarily with the effects of evaporation, temperature, light and air currents upon the behaviour and activity of the insect. Recently, the work has been extended to include studies of the stages which can be dispersed by air currents and studies of certain aspects of the microclimates of the habitat.

On July 30, 1947, what appeared to be the nuptial flight of the above species occurred in the home of a resident of Windsor, Ontario. Hundreds of males and females appeared suddenly from the base of the toilet in the bathroom on the ground floor of the cottage and flew to the open screened window. Dr. William S. Creighton, who identified the species, has remarked that the choice of such a nesting site was certainly unusual for an ant which normally nests outdoors.

An inexpensive, simple, chemical control of wireworms in land to be used for vegetable production has long been sought in the Prairie Provinces. Existing methods of control (3, 4, 5, 6) are not wholly satisfactory for row crops. The cultural measures commonly advocated (6) will reduce wireworm infestations sufficiently that cereal crops can be grown without serious damage, but they are not usually sufficiently effective that potatoes or other row crops can be produced successfully. Crude naphthalene is the most satisfactory of the chemical methods recommended (3, 4, 5) but it is too costly for material, is difficult to handle and apply, and is effective only under certain conditions of soil, moisture and temperature. As a result, commercial potato production on the prairies has been restricted largely to districts and fields where wireworms are virtually absent.

Importations into North America of shipments of broom corn (Sorghum vugare var. technicum) have always been a source of anxiety to plant quarantine officials. It is well known that the European corn borer, Pyrausta nubilalis Hbn., was almost certainly introduced onto this continent in this commodity (22), a surmise which receives perennial support from the continued finding of this species in consignments from various parts of Europe. Broom corn is usually imported in bales weighing from 100 to 250 pounds each, (Figures 1 and 2) which contain both the brush and anything up to 12 inches of stalk necessary for the proper binding of the broom. It is interesting to note that in the country of origin, after the broom corn is harvested, it is dried and curcd and is then usually subected to the fumes of burning sulphur overnight in a closed room in order to bring about, through bleaching, a uniform yellowish colour desired in the trade. None of these treatments have any appreciable effect on the populations of living borers found in the stalks. In addition to insect pests which feed in or on broom corn as a normal host, other species may use the borings of the normal pests as sites of hibernation or pupation. Under some conditions, no doubt, stalks may be left lying in the field for some time prior to harvesting, and thus constitute a refuge for many potential pests.

During the summer of 1947, the potato inspectors (Dominion Division of Plant Protection) working in New Brunswick and Nova Scotia were given a course in potato aphid identification based on the methods presented herewith. In nearly all cases a high degree of accuracy was achieved in a few hours of practice. The purpose of this course was to aid the inspectors in determining the potential number of leaf roll vectors present. This paper is given with the hope that the method may be of value to others similarly interested.

The author published recently a “Revision of the Genus Nysius in the United States and Canada.” In compiling the data pertaining to the distribution of the species in Canada much assistance was rendered by three entomologists: Mr. G. Stuart Walley, Entomologist of the Department ot the Department of Agriculture, Ottawa; Mr. George A. Moore of Montreal, Que. and Mr. J. F. Brimley of Wellington, Ont.