32 



BITTER PIT INVESTIGATION. 



But the orchardist applied in the early autumn 1| cwt. of superphosphate per acre, and in the 

 early spring 1J cwt. of blood and bone manure per acre. The continuity of the experiment was thus 

 interrupted, and the results cannot be taken for comparison with the preceding ones. The experi- 

 ment must now be regarded as a whole, and consists of the application of special manures for the first 

 three years, and in the fourth year a special dressing of superphosphate and blood and bone manure. 

 The whole orchard was thus manured, including the check plots, and the results show the effects of this 

 system of manuring. A final comparison is made between the previous year with the application of 

 special manure and the present year with the general application of the same manure to each plot. 



WEATHER CONDITIONS AND PREVALENCE OF PIT. 



The rainfall during the critical months of November, December, and January was very light. 

 Then towards the middle of February after this dry spell the rain began to fall when the fruit was 

 ripening, and the record for that month was 1| inches (Appendix II.). During the early spring 

 months it rained heavily, and rough weather set in, which lasted all through the setting season. 

 These conditions, together with a certain amount of Thrip, accounted for the pollination being defective 

 and the crop scanty. 



The apples were picked towards the middle of March, and were irregular in size and shape. The 

 light crop and the dry weather, followed by the February rains, were just the most favourable 

 conditions for the development of Pit. 



In West Australia, unlike the other apple-growing States, the crop was lighter than that of the 

 previous season, and in all cases the varieties subject to Pit were badly affected. 



TABLE XV. 



MANORIAL EXPERIMENTS WITH CLEOPATRA AT MOUNT BARKER ESTATE ORCHARD, 



WESTERN AUSTRALIA 1915-16. 



(1J cwt. of superphosphate and 1| cut. of blood and bone manure applied per acre this season, and 

 undernoted quantities applied per tree in previous seasons.) 



Plot 

 No. 



Manure. 



Per I 

 Treg 62 



$.$ 



H * 



Ibs. 



Ibs. 



( Sulphate of ammonia . . \\ ) 

 1 j Ordinary superphosphate 4| 8 348 47 

 ( Sulphate of potash . . l^ 



CLEAN. PITTED. % PITTED. v, 



. _ _ ~ ^ __ ' _ . . _ Per 



On Wind- On Wind- On Wind- cent - 



Trees, falls. Trees, falls. Trees, falls. Pitted. 



Ibs. Ibs. Ibs. Ibs. 



Remarks. 



270 26 85 84 85 



Sulphate of ammonia . . 1^ 



Special bonedust . . 1| 



Ordinary superphosphate 3 



Sulphate of potash . . 1| 



232 53 10 147 22 73 68 72 



( Sulphate of ammonia . . \ ] 



3 j Special bonedust . . 6 \ 8 128 20 3 90 15 82 83 82 



I Sulphate of potash .. 1JJ 



