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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.

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.

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.

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.