452 Journal of Agnculture, Victoria. [11 Aug., 1919. 



ye) Faulty pruning. Many growers adopt a system of pruning 

 so that their trees have as few as six to eight leaders. 

 These are strong, vigorous, and upright, with corre- 

 spondingly vigorous and superabundant lateral growth. 

 In varieties subject to the disease, no consideration is 

 given to choking back the sap, checking rapid move- 

 ment, opening up the tree for the beneficial influences 

 of light, heat, and air, and the placing the fruit on 

 those parts where development is least likely to be 

 excessive or rapid. Of course, I do not wish it to be 

 inferred that any system of pruning can control the 

 complaint, but certainly no system should be adopted 

 that will accentuate it." 

 The officers of the Orchard Supervision Branch all agree with Mr. 

 Carmody's conclusions. His views are further supported by Mr. 

 McAlpine, who in summing up the results of his investigations concern- 

 ing the control of Bitter Pit in his fifth report in 1916, page 66, 

 writes : — 



" The cause having been considered, the control of the disease, 

 may now be attempted from a rational stand-point. Whatever 

 tends to regulate the " flow of sap " and distribute it to the various 

 fruit-buds so that each receives its due share without being over- 

 gorged, will also tend to prevent pit. It is evident that pruning 

 is a great factor here, and it has been proved experimentally that 

 the pit in a susceptible variety, such as Cleopatra, may be reduced 

 to 4-6 per cent, by this means." 

 Even wh^n the trees have been scientifically pruned and the fruit 

 matures apparently free from infection, the insidious nature of the 

 contributory cause or causes of the disease often enables it to develo]> 

 rapidly at the time of ripening or later when the fruit is stored in the 

 ordinary way. The pitting may, however, be considerably restricted by 

 placing the fruit in a cool store just before the ripe stage is reached, and 

 by keeping the cool chamber at a fairly low and uniform temperature, 

 say 31 to 33 degrees Fahr. Owing to the insidiousness of the disease 

 it is obvious that the work of picking and storing, when commenced, 

 .should be promptly executed. 



The experience of the writer while Government representative on 

 the Croydon Cool Stores Trust, as well as that gained by visiting other 

 cool stores is that it is extremely difficult to keep some varieties, parti- 

 cularly Cleopatra, sound. 



In dealing with cool stores as a means of controlling Bitter Pit, Mr. 

 McAlpine in his fifth report, p. 67, states: — 



"•It was one of the main objects of this investigation to prevent 

 the loss due to this cause in oversea shipments of fruit, and this 

 loss may now ibe prevented by the exercise of common -sense* 

 methods. By keeping the fruit in cool storage at a uniform 

 temperature of 30-32 degrees Fahr., the development of Bitter Pit 

 is retarded, and at the same time the ripening process is arrested 

 This is based upon the well-known principle that at that tempera- 

 ture there is a slowing down of the vital activities, and it is prar 

 tically a case of suspended animation." 

 It would be expensive and difficult, if not absolutely impossible, to 

 maintain in our country co-operative cool stores a temperature 



