10 Jean White: 



Most investigators into this problem have agreed that the 

 disease is more prevalent in a wet than a dry season. After 

 spraying there is a deposit of lead arsenate left on the surface of 

 the fruit which remains as a dry powder after the water ha.s 

 •evaporated. In wet seasons these particles of powder are con- 

 tinually being dissolved by the rain and carried into the interior 

 of the fruit through the breathing pores, which pores under 

 ordinary circumstances increase the size of their apertures in 

 damp weather. 



The present season in Victoria has been an unusually wet one, 

 and as far as I have been able to ascertain, bitter pit has been 

 particularly prevalent. 



Whilst conducting my investigations I visited orchards in 

 ■different parts of the State. Here I learnt that severely pruned 

 trees were apparently more prone to the disease. The effect of 

 this pruning would be to render the fruit more concentrated 

 .and more easily reached by the spray. Almost without excep- 

 tion the orchardists volunteered the interesting information that 

 the better the trees are cared for the more subject are their 

 fruits to bitter pit, and that in neglected orchards the trouble 

 is unknown. I personally visited many private gardens and 

 ■orchards where neither pruning nor spraying is done, and no 

 signs of the defect were noticed, though codlin moth and other 

 troubles were abundant. In Prof. E wart's private orchard in 

 the Box Hill district 46 trees in one portion of the orchard were 

 sprayed with arsenate of lead just as the petals had fallen, whilst 

 34 trees, those in the other portion, were left unsprayed. Eveiy 

 apple, either on the trees or in the storeroom from these two 

 parts was examined, with the result that some fruits from almost 

 all the trees in the sprayed portion were pitted, but no sign of 

 a pit could 1)6 found on a single apple from the trees in the 

 unsprayed portion. During the previous season no spraying was 

 done, and no bitter pit was noticed on any of the trees, although 

 odd cases might have been present, since no detailed examina- 

 tion of each individual fruit was made, as during the present 

 •season. 



Time of the Entrance of the Poison. 



In some apples such as Anne Elisabeth, Cleopatra and Bis- 

 marck, the pitting appears frequently while the fruit is quite 



