Report of the Vegetable Pathologvif. 251 



happy to say this operation is becoming more general every year. 

 While the Bordeaux mixture, with the formula 6'4'40, is now 

 commonly adopted, growers are constantly making inquiries as to the 

 advantages of adding this or that ingredient to the mixture. So one 

 set of experiments were directed to settling this question for a number 

 of substances, such as sulphate of ammonia, sal-ammoniac, saltpetre, 

 and common salt. These experiments were carried out at Mr. A. 

 F. Thiele's orchard, Doncaster, and since detailed results will be given 

 in the next issue of the Journal, it is only necessary to state here, that 

 while 90 per cent, of the fruit on the check plot was affected with 

 spot, the Bordeaux mixture of the 6'4"40 formiila reduced it to 9"6 per 

 cent. There was a slight difference in favour of the addition of 

 common salt at the rate of 1 lb. to 40 gallons of the mixture, there 

 being only 9"4 per cent, of spot in that plot. The Copper-soda 

 mixture was also tried, at the rate of 6 lbs. bluestone and 9 lbs. 

 washing-soda to 50 gallons of water (6"9*50), and the result was 14 

 per cent, of spot. The soda in the mixture does not give the adhesive 

 quality of the lime. 



In these experiments only one spraying was given, on 1st 

 November, and the variety of apple chosen was Yates. A second set 

 of experiments were conducted at Killara on the Buncome apple, but 

 because of the lesser susceptibility to the spot, and, perhaps, also on 

 account of the season being by no means favorable to the disease, no 

 very definite results were obtained, though the sprayed trees were all 

 much cleaner than those unsprayed. 



Bitter Pit. 

 As this disease had been very prevalent at Pakenham during the 

 season of 1901-02, it was considered a suitable locality for testing the 

 effect of various treatments. Mr. Hatfield kindly placed at our 

 disposal a number of his trees, and the Sturmer Pippin was chosen, 

 because this variety had suffered most from the disease. Five plots 

 were selected, in which the conditions, age of trees, &c., were as nearly 

 equal as possible, and there were 10 in each plot. 

 Plot 1. — Complete Manure. 

 2. — Potash Manure. 

 3.— Check. 

 4, — Gypsum. 

 5. — Potash and Gypsum. 



Owing to the peculiar nature of the season, there was very little 

 bitter pit at Pakenham in this particular variety. It was very dry 

 at the beginning of the season, and the fruit grew very slowly. As a 

 o-eneral rule, it is found that if the fruit grows rapidly and matures 

 quickly it is most likely to become affected, but when the season 

 encourages slow growth, and the apples are much smaller than the 

 average, as in this instance, then there is very little of this disease. 



The apples were picked in the beginning of June, and there was 

 no bitter pit to speak of, the fruit not being very large, although 

 there was a good crop owing to the dry spring. There were also 



