REPORT OF THE SOCIETY 33 



Sanders composed of dehydrated copper sulphate, calcium arsenate and 

 hydrated lime, came rapidly into general, use not only in Canada but also 

 throughout the United States and in other countries. Coincidentally better types 

 of power dusters were manufactured, and each year brought a reduction in the 

 price of the materials used due to more up-to-date methods of making and 

 distribuing and to the larger scale on which such materials were being handled. 

 Methods were developed for the utilization of white arsenic as an insecticide 

 in Bordeaux mixture. 



Other lines of investigation have received attention; the compatibility 

 of various insecticides with various fungicides, foliage injuries resulting from 

 sprays and dusts, their cause and prevention, insect repellents and attract ants, 

 new uses for insecticides, relative tests and efficiency of new insecticides, and 

 so on. 



More recently other new lines of work have been commenced. Among 

 the more prominent of these may be mentioned the utilization of nicotine fimies 

 and other gases as insecticides in connection with power-dusting machines, a 

 study of various spray and dust "spreaders" and "stickers" and a study of 

 the absorption of water-soluble arsenic b}' various material'^. 



Investigations of important fruit insects have also been conducted by 

 officers attached to the Annapolis laboratory, such as life-history studies and 

 control of the bud moths affecting apple, the fruit worms attacking orchard 

 trees, the White-marked Tussock moth, the Green Apple Bug, the European 

 Apple Sucker, etc., as well as certain insects affecting field and vegetable crops 

 such as the Army Worm, the Colorado Potato Beetle, etc. For field crop work, 

 a temporary laboratorj' was established at Kentville, in 1923. In insecticide 

 and other investigations, our officers have had close co-operation with Prof. 

 S. Blair_, Superintendent of the Experimental Farm at Kentville. 



The European Apple Sucker, Psyllia mail Schmidb., was first found in 

 Nova Scotia in 1919 in the vicinity Wolfville, and has since spread through 

 Kings county and into the counties of Annapolis, Hants, Colchester, Cumber- 

 land, Halifax and Lunenberg. In order to assist in the prevention of the 

 spread of this insect from the Province of Nova Scotia, the federal Department 

 of Agriculture placed the above areas under quarantine and no nursery stock 

 liable to introduce the pest into new sections is allowed to be moved. In 1920, 

 it was noted that a fungous disease, Entoviophthora spharospenna Fres., was 

 attacking the Apple Sucker, and ]\Ir. Allan G. Dustan was detailed to make an 

 intensive study of the parasite with the end in view of assisting in its natural 

 spread. This work has been remarkably successful, and in areas where the 

 fungus was introduced artificially in 1922 and 1923, the Apple Sucker was 

 practically exterminated. The provincial entomological laboratory at Wolf- 

 ville was placed at our disposal. In 1920, Mr. Dustan also undertook a study 

 of a fungous disease parasitic on the Green Apple Bug, Lygus communis 

 novascotiensis Knight . 



The winter scouting work for the nests of the Brown-tail ]\Ioth, conducted 

 bj^ the Division of Foreign Pests Suppression, in co-operation with the provin- 

 cial Department of Agriculture, has assisted very materially in controlling 

 this pest. During the winter of 1913-1914, 24,106 nests, containing living 

 caterpillars were gathered. This number has been noticeably reduced during 

 succeeding winters; in 1922-1923, only 492 winter nests were found. Altogether 

 during the ten years under review 73,756 nests were collected in this province. 

 Mr. F. C. Gilliatt has been locally responsible for the carr^'ing on of this 

 work during the past five years. 

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