Bitter Pit in Apples. 29 



A very important point is to l)e noted in the Burnley Gardens 

 records given as an appendix, namely, that varieties which in other 

 places are given as immune, or nearly so, to bitter pit, appear to 

 he very liable to it when grown in the Burnley orchard. Thus the 

 degree of affection of certain varieties by bitter pit is as follows : — 



For orchards tfenerally. ''"^^ill^ae!;"""''' 



Kome Beauty - Slight to very sliufht - Bad 



Munroes Favorite - Very Blitrht - Slif^ht 



London Pippin - Very slight - Had 



Dumeiows Seedling - Slight - Bad 



Gravenstein - Very slight - Slight 



Statesman - Slight - Bad 



Now for many years the Burnley Gardens have probably been 

 the most thoroughly sprayed piece of ground in Victoria, and pos- 

 sibly in Australia. In France, it has been found that of the total 

 copper applied as sprays during twenty years, one-half to two- 

 thirds was retained by the soil, and could be recovered on analysis. 

 At the Lausanne Viticultural Station (Switzerland) the surface foot 

 of soil was found to have accumulated 3.5 parts of copper per 

 100,000 of soil, and in other vineyards as much as 11 parts per 

 100,000 were found. These figures are well within the limit of 

 toxicity to the pulp cells of apples, even without any accumulation 

 or absorption. It would be of interest to have an analysis of the 

 Burnley orchard soil both now and after an interval of some 

 years. 



The British Board of Agriculture (Journal, vol. xix., p. 751, 

 1912) has recently carried out experiments to determine whether 

 copper which is used in spraying or treating potatoes for various 

 diseases, can be absorbed by the tubers, and to what extent. In 

 the following table of the results obtained the numbers give the 

 grains of copper found per lb. of the dry weight on analysis of the 

 harvested tubers : — 



75 lbs. Strawsonite 75 lbs. Copper Sul- ,, . . . 



per acre. phate per acre. "^ ntrerxteo. 



Peel. Pulp. Peel. Pulp. Peel. Pulp. 



Lancashire plots - 1.44 - 0.10 - 0.16 - 0.08 - 0.12 - 0.07 



Kew plots - - 0.08 - 0.045 - 0.094 - 0.05 ! - — . _ 



The highest amounts in the pulp would not be appreciably greater 

 than 1 part of copper per million of the dry weight, and since only 

 living tubers would be harvested and tested, the cells of potatoes 

 seem to be less sensitive to copper than the pulp cells of apples. 

 The " untreated " soil must have contained a fair proportion of 

 copper, and the lesser absorption from the Kgav plots is probably 



