CONTROL OF CODLING MOTH IX ARID REGIONS. 73 



The spray was thrown through a Bordeaux nozzle set at almost 

 its widest limit on the broadest side, and under a pressure of from 

 85 to 120 pounds. Paris green was used, without lime, at the rate of 

 1 pound to 120 gallons of water in all tests. (This could only be 

 done in an arid climate.) Duplicate series were carried through 

 with pounds of lead arsenate to 120 gallons of water in three cases 

 without showing any difference in results. 



Heavy rains followed the sprayings in several cases, without lower- 

 ing their killing value enough to be noticeable. This was no doubt 

 due to the fact that the effective j)oison was placed in protected 

 places. 



HOW THE EARLY WORMS ARE KILLED. 



In these experiments very few worms of the first brood have been 

 observed to go in on the free surfaces of the apples, and those mostly 

 the later ones. Over two-thirds of this brood, on an average, went 

 in at the calyx and most of the rest were found under leaves where 

 apples touched, or were going in at some scar. Of those going in 

 at the latter situations, no definite observations have been made a- t<» 

 how they are killed. That three- fourths or more of them are killed 

 by the two sprayings has been repeatedly demonstrated. Examina- 

 tions have shown that where two apples touch, a driving spray will 

 often leave a film of poison around the spot, due no doubt to capillary 

 attraction holding the liquid there until it dries. The same thing was 

 true, but to a less extent, with touching leaves and scars. In fact, 

 more poison was found in such situations from the driving spray 

 than from a mist spray applied so as to give the maximum amount 

 of surface coating. This may well account for a considerable number 

 of those killed, but the entire subject is one for further investigation. 



Of the fate of those going in at the calyx we are more fortunate in 

 having definite information. In cutting the thousands of apples 

 examined for poison a number of small worms were found in the 

 lower cups; most of these were found crawling around, but in several 

 instances dead ones were found where there was no sign of their 

 having started to penetrate. More cases were found where a hole 

 had been eaten a short distance into the pulp before the worm had 

 died. In every instance where a dead worm was found poison was 

 found in the lower cup. 



Later an orchard was found that had borne a large and very wormy 

 crop the previous year, and was now bearing a very light one. It 

 had received one driving spray, and was being examined to find out 

 whether late ones would be necessary just as the greatest number of 

 the first brood worms were appearing. Some of the apples already 

 showed castings in the blossom end: of the rest, an average of about 

 1 in 3 or 4 contained a live worm crawling around in the calyx, and 



