72 BITTER PIT INVESTIGATION. 



SUMMARY FOR IRRIGATION. 



The comparative experiments conducted at Bacchus Marsh with Sturmer Pippins, irrigated 

 once and twice respectively, do not show any great differences in the amount of Pit. In the first 

 season, 1911-12, when the rainfall was the highest recorded for 35 years, there was a difference of 5 per 

 cent, in favour of the twice irrigated, but in the two succeeding seasons the rainfall was comparatively 

 low, and very little Pit developed. 



Rainfall. 

 Inches. 

 29-23 

 15-78 

 16-07 



F. COLD STORAGE EXPERIMENTS. 



As a preliminary to keeping the fruit in cold storage, I had the freezing point of the juice of 

 apples and pears determined by Mr. P. R. Scott, Agricultural Chemist. The varieties of apples were 

 selected when they were ready for picking for export, and two early varieties were chosen in the 

 first instance. 



The freezing point of Gravenstein was determined as 28-31 degrees Pahr.; and of Lord Suffield, 

 29-15 degrees Fahr. 



Two samples of Cleopatra, which is a mid-season variety, from irrigated and dry areas were 

 also tested, with the following results : From the irrigated orchard, 28 '98 degrees Fahr.; and from 

 the dry orchard, 28" 80 degrees Fahr., so that there was very little difference in their freezing points. 



A variety of pear was also taken at the same time for comparison Beurre de Amanalis and 

 the freezing point was slightly lower than that of Cleopatra, being 28 65 degrees Fahr. 



These tests serve to indicate that apples and pears are able to stand a temperature of 32 degrees 

 Fahr. without freezing, and it has already been shown in Report III. that they may be continuously 

 kept in cold storage with a variation in temperature of only one to one and a half degrees. 



From the experimental plot at the Yanco Government Farm, the first irrigation farm started 

 by the New South Wales Department of Agriculture under the Great Northern Murrumbidgee Irriga- 

 tion Scheme, the produce of the four Cleopatra apple trees was placed in cold storage on 21st February. 

 They were all wrapped and carefully packed as for export, and there was no visible sign of Bitter Pit. 

 They were kept at a temperature not exceeding 32 degrees Fahr., and not falling below 30 degrees. 



At the end of three months they were removed on 21st May, and every apple examined. They 

 were all found at the same stage of ripeness as when packed, and no rotting occurred. The case 

 containing 130 apples had no trace of Pit ; that with 108 had two pitted ; another, with 55, had no 

 Pit ; and the fourth, with 62, had 1 pitted. 



The pitting always developed towards the "eye" end of the apple, and only one was distinctly 

 pitted with 10 depressions ; while the other two had only a few pits and would be considered quite 

 marketable. 



These were the results obtained after keeping for three months ; and Mr. W. French, Engineer- 

 in-charge of the Government Cool Stores, informs me that he has kept Jonathan and Five Crown 

 apples for nine and ten months in splendid condition after being wrapped and nailed up. 



