168 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 6 



If we compare the efficiency of spraying in the production of sound 

 fruit (chart number 2), we see that there was but 1.29 per cent differ- 

 ence betAveen the twice sprayed and the thrice sprayed blocks. We 

 must take into consideration, however, that the varieties differ and 

 that the block sprayed three times contained blotch susceptible 

 varieties, and the hardest apples to keep clean, grown in our state. 



COMPARISON OF CODLING MOTH INFESTATION IN SPRAYED AND UNSPRAYED ORCHARDS 

 Chart No. 3 : 81,457 Apples Counted 



In a comparison of codling moth infestation in sprayed and un- 

 sprayed orchards (chart number 3), we find that the per cent of cod- 

 ling moth infest iit ion of dropped apples was much heavier in the 

 unsprayed orchard than in the sprayed, and when we come to com- 

 pare the percentage of infestation in picked apples, we discover that 

 in the unsprayed blocks 19.2 to 49.5 of the fruit was wormy, while in 

 the tAvice sprayed block three out of the four varieties produced less 

 than one per cent of wormy fruit. In the block sprayed three times 

 the infestation ran just a little higher. 



If there were time it would be interesting to make a comparison of 

 the varieties of apple in regard to their ability to withstand the in- 

 festation and still remain on the trees; for a comparison of the per- 

 centages of the infestation of picked apples and the percentages of 



