10 Aug., 1918.] " Black Spot " and " Leaf Curl. 



479 



"BLACK SPOT" AND "LEAF CURL." 



(W. Laidlair, B.8c., Biologist; and C. C. Brittlehanh, Vegetable 



Pathologist.) 



During the last four seasons experiments have been carried out for 

 the purpose of testing the efficacy of different sprays on " Black Spot " 

 of the apple and " Leaf Curl " of the peach, and also to ascertain the 

 most effectual time for their application. 



Row of Statesman — sprayed Twice. 



Experiments during the first two seasons were made at the orchards of 

 Mr. C. Nickell, at Drouin, and at Mr. Peart's, Picnic Point, Bairnsdale, 

 l)ut subsequent tests have been conducted entirely at Drouin. These 

 orchards are very liable to the attacks of " Black Spot " and " Leaf 

 Curl." The former because of the high rainfall of the district and the 

 retentive nature of the subsoil, the latter owing to the situation of the 

 orchard on rich river flats where it is impossible to culitvate, as periodic 

 floods wash away the soil. Ideal conditions exist, therefore, at both places 

 for the growth of fungoid pests. Clover, grass, &c., springs up very 

 luxuriantly, as will be seen from the photographs, and this vegetation, 

 together with the heavy dews and river mists, keeps up a dampness 

 favorable to the development and spread of fungus. 



At the start of our experiments, the following mixtiires were used, viz.: — 



Bordeaux, 6.4.40; 



Copper soda, 6.8.40; 



Lime sulphur, 1 in 9; and 



Acetate of copper (verdigris), 3 lbs. to 40 gallons of water; 



