Bitter Pit in Apples. 7 



author in October, 190'7, remarks that arsenite of lead has 

 been the most successful spray used in the Bendigo and Harcourt 

 districts during the past two seasons. 



In July, 1907, on page 389, Mr. J. G. Turner writes: "The 

 quality of the fruit was, on the whole, far in advance of the 

 previous years ; very little was condemned by the inspectors, 

 and in every instance bitter pit was the offending disease." 



In D'ecember, 1907, Mr. A. A. Hammond, on page 721, 

 advises as follows : — " Spray with arsenate of lead when the fruit 

 sets, and the spraying should be repeated sufficiently often to 

 keep the fruit protected by the mixture whilst it is on the tree. 

 If no rain falls 14 to 21 days may elapse between the sprayings. 

 Spraying need not be done after the 15th March for late fruits, 

 and 14 days before picking for earlier ones." 



I have been informed that Mr. Pescott, of Burnley, recom- 

 mends spraying with arsenate of lead six times during the season. 



The Agricultural Journal of the Union of Soutji Africa^ 

 specifies the year 1892 for the introduction of lead arsenate as 

 a spray for the elimination of codlin moth. From the above it 

 seems to be an indisputable fact that compulsory spraying and 

 the occurrence of bitter pit trouble have apparently simul- 

 taneously increased in our orchards. I now proceed to detail the 

 results of my own observations and experiments which have led 

 me to the conclusion that bitter pit is the direct result of 

 spraying the fruits with poisonous liquids. 



As the great bulk of material used was obtained from the 

 Burnley Gardens, and as lead arsenate is the spray which is com- 

 monly employed there, I have practically confined my attention 

 to the investigation of the effects produced by this material, 

 which is a sparingly soluble compound, and is therefore 

 poisonous, 3 though I do not wish to infer in any way that 

 this is the only spray which would produce the trouble. It is 

 not, consequently, according to Massee,'^ a satisfactory spraying 

 material. 



Mr. Pole Evans, in his constantly referred to paper on bitter 

 pit, states that though bitter pit seems to occur in most apple- 



1 Vol. i., No. 2, March, 1911, p. 249. 



2 Principles of Chemistry, Mendeleef, vol. ii., p. 136. 



3 Diseases of Cultivated Plants and Trees, p. 53. 



