THE INSECT CAMPAIGN IO5 



from the continued work of the insect. A strong, pha- 

 ble copper wire, however, is better than a knife in most 

 cases ; and if taken in combination with the knife makes 

 the best set of instruments for fighting the borer. This 

 pHable copper wire can be thrust into bores made by 

 the larvje, and will kill a majority of them without 

 making it .necessary to cut open the tree. 



Codling Moth — This is one of the best known and 

 most widely distributed enemies of the apple. Newly 

 settled districts have nearly always enjoyed a tem- 

 porary immunity from this pest, but experience has 

 shown that the moth cannot long be kept out of any 

 commercial apple-g'ro*wing district. Apparently the 

 ravages of the codling moth 'are more serious in -cen- 

 tral "and southern latitudes, where two or" three, or even 

 as many as four, broods are hatched in a year. How- 

 ever, 'the campaign against this insett is an annual one, 

 and has to be fought in practically all the commercial 

 orchards in the country. 



The principal preventive of damage is the spray 

 pump, using poison sprays. Paris green is largely used 

 at the present time, but is being somewhat generally 

 supplanted by lead arsenate (see formulas on page 

 142). Thorough spraying at the right time with these 

 insecticides will very greatly reduce the percentage of 

 damage. Indeed, in many cases the work of the insect 

 is practically eliminated. As in dealing with every 

 other insect or fungous pest, thorough spraying at the 

 proper time is highly essential. The proper time in 

 this case is within one week to lo days after the fall- 

 ing of the blossoms. A longer delay cannot be made 

 with safety. After about lo days the calyx, or blos- 

 som leaves of the young apple, close and the apple 

 turns to a pendant position. Before this time the newly 



