The Cherry Fruit-Fly. 37 



does fall or is picked. But afflicted cherry growers state that but 

 few, if any, infested cherries fall prematurely, and also that there is 

 no way of distinguishing the infested cherries from the others at 

 picking time. 



Hence there seems to be no practicable method of getting at the 

 pest while it is in the fruit, except the heroic method of picking 

 and destroying by boiling, burying, or otherwise, the whole crop on 

 the infested trees just about tlie time the first fruits are ready to 

 pick, or even before. This method, of course, involves the loss of 

 the cherry crop for a season, but it is the only sure method we can 

 conceive of to completely check the pest. Usually certain trees or 

 certain varieties will become infested first, and the destruction of 

 the crop on these few trees would not count for much as against 

 their being a constant source of danger to the rest of the orchard. 

 The pest could be quickly stamped out in this way, and as it spreads 

 very slowly, it might be a long time in again getting a foothold in 

 the orchard. This method of destroying the crop of cherries for a 

 season, while it is an heroic one, it yet deserves to receive the serious 

 consideration of cherry growers who may be unfortunate enough to 

 have this cherrv fruit-flv to combat. 



As the insect spends ten months or more of its life in the soil, 

 usually less than an inch below the surface, it would seem as though 

 some method might be devised to check it then. All of this time is 

 spent in the pupariam stage (figure 15), and as we have stated above, 

 while in this form the insect would not be readily affected by 

 insecticides of any sort. We doubt if any of the puparia could be 

 killed by the application of any reasonable or practicable amount of 

 any insecticide, especially such substances as the commercial fertil- 

 izers, ffas lime, lime or salt. Gas lime has been tried in Australia 

 with no success. 



As the puparia are so near the surface of the soil from July until 

 the following June, it would seem as if thorough cultivation might 

 be successfully employed against the pest. But it is evident that 

 the usual methods of cultivation employed by our most successful 

 orchardists lias little or no effect on the pest, for those who suffered 

 from it this vear were mod, thorough cultivators. A possible 

 explanation lies in the fact that the puparia are too small to be 



