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Experimental work in the orchard, supported by laboratory tests, demonstrates that spring cultivation (plowing followed by thorough discing) will destroy 100 per cent of the overwintered larvae and pupae of the Oriental Peach Moth, Laspeyresia molesta Busck, on the ground about the tree; and, that such cultivation to be most effective must exceed the depth of three inches. In a spraying and dusting experiment, a combination fungicidal-lead arsenatenicotine (1-800) spray showed the highest efficiency of any treatment, resulting in an increase in clean fruit amounting to 13.3 per cent. Under average conditions, such a spray should offer a return of approximately twenty cents per bushel over and above the additional cost in spray material.

Preliminary laboratory tests with coarsely ground automobile tire mica dusted on peach foliage showed that a high per cent of 'newly hatched larvae of the Oriental Peach Moth were killed before they reached a point of entry. More extensive laboratory tests with a number of dusts showed that finely ground talc and mica killed a high percentage of Oriental Peach Moth larvae hatching from eggs on peach foliage dusted with these materials. Limited field tests with talc and mica showed that talc sticks better and is more effective than mica or hydrated lime in reducing larval entry into peach twigs. Limited tests with talc and mica dusted on foliage containing Codling Moth eggs showed that the young larvae of this insect are killed by both materials.

Many species of moths are attracted to light, particularly to artificial lights in darkness. It is a well known fact that oriental peach moths, Laspeyresia molesta Busck, and codling moths, Laspeyresia pomonella L., congregate on the light side of screen cages or glass containers, consequently it may be assumed that the adults of both species under certain conditions, are positively phototropic.

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Laboratory experiments with white oil-pyrethrum sprayed on new and old peach twigs showed that newly hatched peach moth larvae ( Laspeyresia molesta ) are killed more easily when they crawl over sprayed new growth than sprayed old growth. The difference appeared to be due to the greater absorptive power of the old growth for the oil. Field spraying tests in which white oil-pyrethrum was used at 0.5 and 1 per cent on a five day schedule against third brood eggs and larvae showed a reduction in invisible fruit infestation of from 60 to 75. Visible fruit infestation, which was comparatively high at the time the spraying operations were begun, was reduced much less by the spray so that the combined visible and invisible injury gave a total reduction in fruit infestation of from 30 to 70 per cent. The effect of parasites on the seasonal activities of the peach moth and their relation to spraying operations are discussed.

Males and females of the oriental peach moth, Laspeyresia Molesta Busck, come to molasses-yeast baits. Usually adults come to the baits near sunset each day when the temperature is above 55°F and when it is not raining. A bait is most attractive for a few days after it is made or replenished with dilutemolasses. It may continue to attract adults for 50 days or longer without renewal. By means of traps containing a molasses-yeast bait it is possible to determine by daily observations the presence and relative abundance of the adults in the orchard. One season's observations indicate that males arc present in larger numbers than females during the early part of the emergence of each brood, while females occur in larger numbers than males during the later part of each emergence period. This is particular]y true of the first and second brood adults.

By applying Dyar's ideas that the width of the head-capsule of a lepidopterous larva is more or less constant for any instar of a given species and that successive e larval instars of a given species show. a more or less regular geometric progression in the growth of the head-capsules, oriental peach-moth larvae are found to have four or five instars. The number of larval instars produced is correlated with the rate of larval growth. As a rule rapid growth produces four instars and slow growth five instars. Rapidity of larval growth is dependent upon at least two factors, temperature and food. High summer temperatures produce rapid growth while low temperatures, such as occur in the spring and fall, produce slow growth. Larvae develop somewhat faster in peaches than in apples under insectary conditions. The rate of development of individual larvae in a given food varies Considerably.

The writer used several methods for testing repellency in a series of experiments at Riverton;New Jersey, in 1927. Recording the eggs deposited on sprayed twigs in cages (in the insectary), and recording the number of moths coming to bait pans, with and without evaporation cups containing chemicals (in the orchard), seemed the best methods. In the insectary tests, sprays of crude alpha naphthylamine and Dippel's oil gave the most satisfactory results. The orchard tests revealed four chemicals-furfural, Dippel's oil, ammonium sulphide and amyl acetate-which showed at least 50% repellency. An apparatus for use in field studies with repellents is described.

While making peach twig collections for parasite recoveries during the first part of June, a few Chrysopid adults were observed throughout the orchards. No particular attention was paid to this insect until late in July, when adults could be found on almost every tree throughout the orchards of the Niagara district. Several specimens were sent to Ottawa for determination and it was found that two species were represented, viz., Chrysopa oculata Say. and Chrysopa albicornis Fitch., the former being by far the more numerous. Eggs began to appear the latter part of July and could be located in numbers varying from one to four on almost every tree.

The Oriental peach moth (Laspeyresia motesta Busck) was first found in the South in the fall of 1923. Since that time inspections have revealed its presence in several localities of each of the Southern States, except South Carolina and Louisiana. Typical injury has been reported from those States. It is believed that the insect was brought into the South in infested apples, Studies of the life history and habits of the insect at Fort Valley, Ga., showed the occurrence of six generations and a partial seventh in 1925, and five generations and a partial sixth in 1926. The use of bait pans for the control of a light infestation of the Oriental peach moth, such as occurs in Georgia, was unsatisfactory and impracticable. Neither in the past, nor at present, has the Oriental peach moth been of any economic importance in Georgia. Because of the absence of a host, to mature the broods of larvae that hibernate, the Chances are that it never will be a pest of major importance in the Georgia peach belt. The original light infestation in Georgia has shown a marked decrease during the last two years. At the present time the known infestation is confined to trees in several cities and towns, and to a part of only two commercial orchards in the peach belt.

The problem of controlling Laspeyresia molesta Busck still challenges entomologists and fruit growers. To date no insecticidal control or orchard practise is known which is satisfactory or practical. The writer summarizes the more important factors that influence and limit the different artificial control measures. He also expresses his opinion on future possibilities of finding an insecticidal control measure based on ten years experience with the insect. Ovicides, larvacides, dormant control measures, light traps, attractants (baits) and repellents are discussed.

Oriental peach moths are attracted to fermenting molasses baits from the middle of April until the middle of October. Some or many males and females may be found in the bait containers every day during the entire season. This year, 1925, at Riverton, New Jersey, the largest number of adults were captured during the emergence period of the first brood moths. Later broods were reduced by parasitism. The graphs show that more moths came to the same sort of bait located in peach orchards than in apple or quince orchards. An enameled stewpan has proved to be the most satisfactory container for baits. So far as known bait containers should be well filled in order to catch the maximum number of adults. Containers placed high in the tree catch more moths than those placed low. Cheap stock-feeding molasses seems to be the most satisfactory grade of molasses for baits. Dilutions of 1–10 and 1–20 are more satisfactory than weaker or greater strengths. Yeast is unnecessary. Under most conditions natural fermentation makes a better bait than where yeast is added. Corn syrup, particularly the colorless grade, diluted 1–20 with water, attracted large numbers of moths.

Results of two methods of handling parasitized oriental peach moth material in transferring Macrocentrus ancylivora Rohwer are given. Retention of the material at the point of collection until the pupal stage is reached is considered the better of the two methods.

A number of the bait experiments of previous seasons for Laspeyresia molesta were repeated and in most cases the results obtained were duplicated. Enameled stewpans and wide mouth, glass, quart jars proved to be the most satisfactory containers. Some 250 aromatic chemicals tested. Terpineol and several essential oils (fennel, Bergamot, star anise, anise seed and Pinus sylvestris ) were somewhat attractive to moths. If one compares attractiveness of anyone of these products with that of several fermenting sugar-possessing it is much less. Fermenting fruits (dried fruit in water), particularly prunes, pears and apricots, attract a goodly of moths. Baits made of cheap black-strap molasses (5 to 20 per cent dilutions) are fairly attractive but they usually produce considerable their period attractiveness is not very long. Honey, corn syrups, refiner's syrups and brown sugar (5 or 10per cent solutions) are much more attractive than black-strap molasses. These products an(1othels of a similar nature produce little or no scum when fermentation occurs and their period of attractiveness is of considerable length (several weeks). Fermentation or some change occurs in all baits made of sugar-possessing commercial products before they become very attractive to the oriental peach moth. Several of the common disinfectants delay but do not permanently prohibit fermentation when added to the sugar-possessing products used in the experiments.

Field experiments in control of the Oriental peach moth, Laspeyresia molesta , in 1929 showed no control for talc dust and slight reductions for lime and oil combinations. Laboratory ovicide experiments under insectary conditions showed good kill for oil preparations, particularly oil and pine oil combinations.

Results are given of two years experiments in colonizing Macrocentrus ancylivora Roh. in the area of new infestation of the oriental peach moth ( Laspeyresia molesta Busck) in western New York. The parasite has apparently established itself in this region. Glypta rufiscutellaris Cress. and Ascogaster carpocapsae Vier. were found to parasitise the peach moth in western New York in 1927, altho the percentage of parasitism was negligible. In 1928 Glypta parasitised 12 per cent of the larvae of the peach moth and in 1929 only 0.71 per cent. In both of these years Ascogaster was of rare occurrence. In 1929 twig collections from the Hudson Valley and Long Island showed a parasitism by Macrocentrus of 51 and 89 per cent respectively. Seven hundred thousand Trichogramma minutum Riley liberated in one orchard parasitised 36 per cent of the season's eggs.

Agricultural articles in this issue pertain to the seriousness of the Oriental Peach Moth infestation, how the scrub bull campaign has improved bull conformation, and livestock in Cuba. Other articles address the benefits of ultra violet light, a freshman's first impressions of Canada, and notes from the English Department. Campus news reports on how the freshmen initiation became a serious matter of unacceptable hazing, the seasonal athletic activities, and the various wiener roasts and dances. The Alumni column provides an update of alumni activities and a letter from an alumnus experiencing the war conditions in China. The Macdonald Institute column includes a report on the women's field day, and alumnae updates. The Oriental Peach Moth in Ontario Canada's best bulls Ultra-violet light Live stock in Cuba First impressions of Canada English Department notes and news Editorial College life Athletics Alumni Macdonald advertising

Results are given of the season's experiments with twenty insecticides to control the oriental peach moth. Partial reduction of infestation was secured in all cases. A report of the third season's work in colonizing Macrocentrus ancylivora Rohwer is included. The area previously colonized showed a parasitism of 54.54 per cent, a 390 per cent increase over that of last year.