CONTROL OF CODLING MOTH IN ARID REGIONS. 75 



killed was no more than was to be expected. Apples from trees twice 

 sprayed in June, 11)05, were exhibited in February and March, 1900, 

 at the Northwestern Fruit (Jrowers' Convention and the Idaho Horti- 

 cultural Society, and in the majority of ihciii poison could still be 

 detected. 



CONCLUSIONS. 



(1) The j)oisons used in the intermountain rejrion have l>een satis- 

 factory. 



(2) The codling moth is delinitely two-brooded in tliis region. 



(8) It is so abundant that from .5 to 8 ordinary sprayings have 

 been necessary to control it. 



(4) The driving sprays force the poison inUj I lie calyx cups and 

 into the cracks and spaces between the apples where the first-brood 

 worms enter. 



(5) The first early spraying is the best, the second is nearly as 

 good, and the third is of little value. 



(G) Two early driving spi-ayings will kill an average of 90 per cent 

 of the first l)rood of worms. 



(7) h\ killing these woi-nis in the fir^t bi'ootl the greatei- part of 

 the second brood is prevented from api)earing. 



(8) Sufficient poison is retained from the early sprayings to kill an 

 average of 74 per cent of the second brood of worms. 



(9) Two early sprayings correctly applied are woi-ih from (> to 10 

 times as much as three late ones. 



(10) Over two-thirds of the first brood and nearly two-thirds of 

 the second brood of worms enter the calyx. 



(11) Of these worms entering the calyx, an average of 98 per cent 

 of the first brood and 97 per cent of the second were killed by the 

 two early sprayings. 



(12) Of the worms entering the sides, an average of 78 per cent of 

 the first brood and 52 per cent of the second were killed by the same 

 sprayings. 



( 13) Each succeeding year of such sjjraying will reduce the number 

 of worms remaining in the orchard. 



Mr. J. B. Smith inquired if there was any special explanation why 

 an early and a late spraying of Disparene showed a larger per- 

 centage of perfect fruit than when three sprayings were applied and 

 Bordeaux mixture was added to the first tAvo ; also, whether Bordeaux 

 mixture seemed to afl'ect the efficiency of the poison. 



In reply. Mr. Burgess stated that he could give no leason for the 

 better showing nuide where only two sprayings were applied. In 



