In the late 1940's significant increases in the population of the spruce budworm, worm, Choristoneura fumiferana (Clem.), occurred in northern New Brunswick and culminated in a severe outbreak of this major forest pest. The outbreak has been the subject of intensive investigations dealing with emergency chemical control operations (Webb, 1956) and with a long-term study of the population dynamics of the budworm. The latter program, called the Green River Project, is located on the Green River Watershed in northwestern New Brunswick. Its objectives, the co-operating agencies involved, the mortality factors being studied, and methodology have been discussed elsewhere by Morris et al. (1956), Morris (1951), Morris and Miller (1954), and Morris (1955).

The clover cutworm, Scotogramma trifolii (Rott.), has been recorded from a wide variety of host plants, but there are few records in the literature associating it with cole crops. Riley (1893) recorded it from cabbage in Maryland. Gibson (1915) recorded it from turnip and cabbage in Canada. Forbes (1951) and Frost (1955) listed cabbage as a host plant in New York and Pennsylvania, respectively. In 10 years' studies on caterpillars on cabbage in the Ottawa VaIley, 1949 to 1958, numbers of the clover cultworm on cabbage were almost always negligible. However, in the early summer of 1956 it occurred throughout the area in significant numbers, and in a study field of early cabbage at Merivale, Ontario, caused sufficient damage to affect the market value of the crop.

The European pine shoot moth, Rhyacionia buoliana (Schiff.), was introduced accidentally into Ontario about 1925, and has since spread throughout the southwestern part of the province south of a line from the south shores of Georgian Bay on the west to Brockville on the east (Fig. 1). Damage to the host is done by the larvae, the feeding of which results in the deformation of the branches and main stems, reducing the potential value of the trees as timber and, in heavy infestations, making young trees unsuitable for the Christmas tree trade. Several species of exotic and native pines are attacked; red pine, Pinus resinosa hit,, Scots pine. P. sylvestris L., and Mugho pine, P. mugho Turra, being the most susceptible. Because of the extensive planting of Scots and red pine in southern Ontario, especially during the last 25 years, the increasing numbers of European pine shoot moth in this area present a problem of great importance. Contributing to an understanding of this important pest, this paper presents a detailed review of the parasites obtained in Ontario since 1954, with some notes on earlier surveys.

The genus Linosta was described by Möschler (1881: 433) for the single species L. sinceralis Möschler from Surinam. There have been few subsequent published references to the genus, but in most collections it stands in the Schoenobiinae. Amsel (1956) surveyed the structural characters and noted that the genus did not fit very well into the Schoenobiinae or any other subfamily and that it would possibly require its own subfamily “Linosterinae”, but he left it in Schoenobiinae for the time being. In my opinion the group is sufficiently distinguished from the Schoenobiinae by the absence of proboscis, of maxillary palpus, of chaetosema, and of tubular 1st A of primary, as well as by the different tympanic and genital striucturc. The absence of the maxillary palpus would place the genus in Chrysauginae, but the joining of the tympanic bullae and the presence of a definite praecinctorium (new term for tablier of Guenée = Schürze of Lederer = Kielhäutchen of Amsel) rule this out. The group obviously belongs in the basal part of the crambine-pyraustine complex; the actual affinity appears to be to the Cybalomiinae (new subfamily, type genus Cybalomia Lederer, characters of Crambinae, but with chaetosema absent). The male genitalia agree well with those of Cybalomia and Stiphrometasia, especially in the close association of the base of the gnathos with a strap-like sclerite connecting with the costal articulation of the valve. Also the tympanic structure is closely similar to that of Stiphrometasia and furthermore to that of Thyridophora, which has a fovea and associated stalking of R5, and M1, just as in Linosta, and which also lacks the proboscis.

No research has previously been conducted on gall aphids on poplar in Alberta. Strickland (1953) published records of some of these aphids in his list of Hemiptera of Alberta. Manson (1931) mentioned that noctuids fed in galls of Pemphigus populitransversus Riley.

In the United States, several workers have reported on these aphids. Palmcr (1952, pp. 358-372) published a key to and some bioiogical notes on several species of the genus Pemphigus and related genera. Maxson and Knowlton (1929) gave considerable information on the life-history and classification of the tribe Pemphigini. Maxson (1923) and Hottes and Frison (1931) published keys to the same tribe. Essig (1926, pp. 259-261), Gillette (1913). Gillette and Bragg (1915), Jackson (1908), Oestlund and Hottes (1926), Patch (1913), Swaine (1919), and Williams (1910) also reported on some of the gall aphids on poplar.

The Forest Insect Survey at the Forest Biology Laboratory, Winnipeg, has been compiling records for a number of years on the percentage of cocoons of the larch sawfly, Pristiphora erichsonii (Htg.), parasitized by the tachinid Bessa harveyi Tnsd. Sawfly cocoons were collected each fall from the soil in infested stands, and those containing living larvae were dissected to determine the percentage of parasitism by B. harveyi. These estimates have been used to provide an index of parasitism (Lejeune and Hildahl, 1954), but are of limited value for a number of reasons: (1) estimates can be expressed only as percentage of sound cocoons parasitized; (2) total parasitism cannot be estimated because a portion of the parasites emerge from the cocoons before collection; and (3) estimates of parasitism may not be representative of the stand because there is a tendency to collect cocoons where they are easiest to find; hence all the cocoons in a collection may be from one or two small areas. If the proportion of cocoons containing B. harveyi varies within a stand such collections may give unreliable estimates of parasitism.

On July 7, 1958, at Churchill Park, St. John's, a number of wasps were observed boring holes into the mortar between the bricks of a private dwelling. A total of 41 holes, three-sixteenths of an inch in diameter and up to three inches in depth, were counted. The majority of these holes faced south and a few faced west. Some were provisioned with small green caterpillars and capped, and others were in the process of excavation. This unusual nesting habit, and the presence of the wasps, caused much anxiety to the owner. One spraying with a five per cent DDT solution, concentrated in and around the holes, eliminated the infestation.

The first North American collection of the European pine sawfly, Neodiprion sertifer (Geoff.), was made in Somerset County, New Jersey, in 1925 (Hamilton, 1943). It was first recorded in Canada near Windsor, Ontario, in 1939 (Raizenne, 1957), and by 1946 it had spread as far east as London (Watson, 1946). This serious pest of pines has continued to spread, and is now found throughout most of southwestern Ontario (Fig. 1) (Sippell and MacDonald, 1958). This is the only infestation of this species in Canada.

This paper is one in a series on sampling techniques used in population studies of the larch sawfly (Ives, 1955; Ives and Prentice, 1958). The technique has been developed to provide bases for comparing the intensity of sawfly infestations in stands of different compositions, and for studying the effect of the insect upon its host. A preliminary study demonstrated the feasibility of developing a sampling method for estimating foliage weight, but also indicated that the foliage weight increased as the season progressed (Ives, 1958). Foliage sampling in stands infested by the larch sawfly must be completed before defoliation becomes prevalent, and the foliage weight may increase considerably after sampling. In 1956 an intensive sampling program was carried out on tamarack in the Whiteshell Forest Reserve, Manitoba, to determine the sample size needed to obtain statistically acceptable estimates of foliage production and to study the nature of changes in foliage weight during the season.

The Douglas-fir beetle, Dendroctonus pseudotsugae Hopk., is a constant threat to Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests because of its ability to kill large quantities of this important timber tree. In the search for more effective control of this pest the need for experimental insects frequently exceeds the supply from natural sources. Laboratory rearing can alleviate this shortage.

During studies on the control of the onion maggot, Hylemya antiqua (Meig.), in late September, 1958, from one to 10 dead adults were found clinging to the tops of onion leaves in a three-acre field of green bunching onions in the Toronto area (Fig. 1). The dead flies were more abundant in the outside three rows, adjoining a non-cultivated grassy area, than throughout the rest of the field. A fungal growth was evident between the abdominal terga and sterna in many specimens. Infected live flies were somewhat pale, appeared bloated, and moved very sluggishly in comparison with non-infected adults. Dead flies were sent to Dr. G. Bucher, Entomology Laboratory, Belleville, Ontario, who identified the pathogen as Empusa muscae Cohn.

The effect on insect populations of the widespread use of plant growth regulators and herbicides is a neglected field. Fox (1948) reported on a relationship between the use of 2,4-D and wireworm damage to wheat. Putnam (1949) suggested that 2,4-D could be an environmental factor in the ecology of grasshoppers. A recent report (Maxwell and Harwood, 1958) indicates that even slight dosages of 2,4-D increase the rate of reproduction of pea aphids on broad beans. This note is a preliminary report on similar investigations with the pea aphid, Acyrthosiphon pisum (Harris), and broad bean, Vicia faba L.