16 



BULLETIN 938, U. 



DEPARTMENT OP AGRICULTURE. 



collected once a week and examined for codling-moth injury, and 

 at picking time the picked fruit was also examined. The results of 

 these examinations are given in Table V. 



Table V. — Codling moth injury as shown by examination of both fallen and 

 picked fruit from experimental plats at Benton Harbor, Mich., 1911. 



No. 



of 



plat. 



Fruit record. 



Number of applications and brief 

 formula of each. 



! 

 Number of larval en- 



trances at — 



Calyx. 



Side. 



Stem. 



191 



277 



14 



5.30 



CG2 



71 



40 



19.5 



4 



2.032 



G07 



93 



Number 



ofwormy 



apples. 



Total 

 number 

 of apples 

 exam- 

 ined. 



Percent- 

 age of 

 total 

 number 

 of apples 

 free from 

 worms. 



1 application of lime-sulphur and 3 

 applications of lime-sulphur + 1 

 pound arsenate of lead to 50 gallons 

 water 



1 application of lime-sulphur and 3 

 applications of nicotine sulphate 

 l:S00+soap 



1 application of lime-sulphur and 3 

 applications of nicotine sulphate 

 l:S00+soap+0.5 pound of arsenate 

 of lead to 50 gallons of water 



1 application of lime-sulphur C check i. . 



33C 6,543 | 94.71 



1.249 j 9,924 | 



231 2.949 92.15 



2.4.S4 8,060 59.00 



Reference to Table V shows that nicotine sulphate (plat Xo. 2) 

 gave a control of only 87.41 per cent, while arsenate of lead (plat 

 Xo. 1) gave a control of 94.71 per cent. There is thus seen to be 

 no practical advantage in combining arsenate of lead with nicotine 

 sulphate in sprays designed to control the codling moth (plats Xos. 

 1 and 3). 



EXPERIMENTS PERFORMED AT GRAND JUNCTION, COLO. 



Experiments similar to the preceding were also performed at 

 Grand Junction, Colo. Of the 12 plats sprayed, only 2 were sprayed 

 with nicotine sulphate, but since the results obtained using arsenate 

 of lead vary so greatly, the data from 4 of the latter plats are given 

 in Table VI, so that the results from the plat sprayed with nicotine 

 sulphate may be compared with those from the plats sprayed with 

 arsenate of lead alone and also with the results from the plat sprayed 

 with arsenate of lead and nicotine sulphate combined. In plats on 

 which it was applied (i. e.. all except plats Xos. 10, 14. and 15), 

 the calyx application was made with a Bordeaux type of nozzle 

 which delivered a fairly coarse and driving spray: a mist type of 

 nozzle was used for all subsequent applications. \Vith this exception 

 the same spraying equipment was used for all plats except the checks. 



At various times throughout the growing season and at harvest 

 time the apples on eight trees in each plat (four in each of the two 

 check plats) were examined: the results of these examinations, to- 

 gether with the treatment of the several plats, are given in Table VI. 



