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drought core, is free of disease and has the appearance of being of good keeping-quality. The whole of the available trees are now in use for manurial trials, while some 109 spraying trials have been conducted in the orchard. Both the Plant Research Station and Cawthron Institute have made use of the orchard for field trials, and have drawn upon it for materials for laboratory investigations. In the nursery some 600 East Mailing selected and 100 Northern Spy stocks have been established, and have now been budded with buds selected from special-type trees of the leading varieties of commercial apples. Improvements have been effected ijj the packing and storage sheds during the year. Meteorological records of a type particularly required in orchard research, have been kept, a fully equipped station having been established. Particular interest attaches to the evaporimeter installed by which it will be possible to have some information regarding evaporation in the conditions of the Nelson climate. In view of the investigations to be undertaken shortly upon drought diseases of apples and pears, this information will prove of much assistance. 2. Botanical Investigations. Stocks.—Girth measurements of some 200 trees of the varieties Statesman, Sturmer, Delicious, Cox's Orange Pippin, and Jonathan, worked on Northern Spy and East Mailing Stocks Nos. I, XII,' XIII, XV, and XVI, representing thirty stock-scion combinations, have shown to date that'those propagated on East Mailing stocks are slightly more vigorous. This work is designed to indicate whether improvements can be effected by the more general use in New Zealand of .these selected East Mailing stocks. Strains of Apples.—Varietal studies of apples, peaches, and apricots have been commenced. Attention is being focused on the Delicious apple in an attempt to overcome the trouble caused by mouldy core, which is due to fungus growth gaining entry to the core of the apple through the calyx remaining open. Various strains selected throughout the Dominion are now being propagated on the early bearing Jaune do Metz Paradise stock, with a view to ascertaining those which are free from this defect. Northern Spy RootstocJcs. Five hundred stocks selected throughout New Zealand from very vigorous, normal, and stunted apple-trees have been grown in the nursery, and it has been found that 90 per cent, of these are Northern Spy stocks of a single botanical type. It appears, therefore, that there is no between the three classes of trees and the rootstock upon which they are established. Experiments have demonstrated that Northern Spy stocks grown from root cuttings, possess a markedly different root system and greater vigour of growth than those secured from layering, which appear weaker and generally shallower. It is obvious that with some of the weaker growing varieties of apples, care should be taken to ensure that these are propagated on vigorous stocks secured from root cuttings. Standardization of Pear Stocks.—Types of pear stocks are being collected from different parts of the Dominion, with a view to testing for an ultimate system of standard stocks. Filberts. —With a view to ascertaining the possibilities of commercial growing of filberts, trees developed in the nursery have been sent to different parts of the Dominion for trial. 3. Entomology. Red Mite: Control by Oil Sprays.—Trials were conducted with twenty-six specially prepared oils on the winter eggs of the two varieties of red mite. Bryobia praetiosa eggs were much more readily destroyed than were those of Paratetranychus pilosus. Quick-breaking unstable emulsions were found to be much more effective than were stable permanent emulsions made with the same oils. The killing-power of stable emulsions was found to increase with viscosity, but with unstable emulsions a 100 per cent, kill was secured with considerably lower viscosity. Field trials showed that winter oils \jrere most effective against red mite, when applied as close as possible to bud movement in the spring. Bronze Beetle : Control by Sprays.—lnvestigations on the control of bronze beetle by sprays has now been concluded. The results show that, maximum efficiency is secured by the use of 4 lb. acid arsenate of lead dissolved in 100 gallons of water, the mixture being applied so that a good even " spot " cover is secured. This can be done by applying the spray in a very fine mist. Spreaders and fish-oil detracted from the efficacy of the arsenate, because they induced an undue amount of run-off. Paris Green, while superior in its killing effect, was liable to cause fruit injury. Barium fiuosilicate gave the same control as lead arsenate, but caused severe burning of the fruit. Apple Leaf-roller. —The results of the bait trap experiments during the previous two seasons were incorporated in a graph showing the flight period of the moth in Nelson. Copies of this graph were distributed to Orchard Instructors. Some further observations have been made on the existing parasites of the leaf-roller and a paper on the most important parasite (Apanteles) has been prepared for publication. Codling Moth.—Graphs showing the flight period of the moth in Nelson during the previous two seasons were prepared and made available to interested persons. In January, 1934, a second consignment of the codling moth parasite (Phanerotoma tibialis) was received from the United States of America. This material consisted of codling-moth larvse said to be parasitized by Phanerotoma. The parasitism must have been very low, as only two parasites emerged from the material. Both the parasites were females and as the product of their unfertilized eggs will probably be exclusively males the prospects for successful breeding of the parasites from this material are slight.

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