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JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 6 



cent and the Winesap, but 3.81 per cent. The Jonathan tree in the 

 unsprayed block had more than 40 per cent of its fruit damaged while 

 the one sprayed twice was injured to the extent of only 6 per cent. 

 The unsprayed Gano showed an infestation of nearly 30 per cent, 

 the one sprayed three times, less than 4 per cent. 



This again shows the inaccuracies that might result from basing 

 spraying results upon the fruit at picking time, for the actual control 

 was not as the above statement would indicate. For instance, the 

 Black Twig in the unsprayed block had less than 4 times the infestation 

 of the sprayed block, while the former figure gave an apparent control 

 of 1 to 6. The Winesap results varied from an apparent ratio of 1 

 to 13 to an actual of 1 to 10. 



An examination of Chart No. 4 fails to show any reason for the third 

 spray for curculio. It is worthy of note in this connection, that no 

 early sprayings were made for this in these experimental blocks, the 

 control being due to those appHed for the Codling Moth. 



COMPARISON OF BITTER ROT INFESTATION IN SPRAYED AND UNSPRAYED ORCHARDS 

 Chart No. 5: 81,457 Apples Counted 



The experimental orchard had been badly infected with bitter rot 

 and though the present season was considered a good bitter rot season, 

 it is interesting to note that it was a negligible quantity in the twice 

 sprayed orchards though running from 4.7 per cent to 11 per cent in 

 unsprayed blocks. 



