COjSTTROL of codling moth in COLORADO. 



tions as plats I, II, VI, and IX, but in plat VII homemade arsenate 

 of lime paste ^ was substituted for arsenate of lead paste, and in 

 plat VIII commercial arsenate of lime powder was used. Plat X 

 was unsprayed for comparison mth the treated plats. 



T.\BLE 2.- 



-Spraying schedule for the codling moth, Johnson orchard, Grand Valley of 

 Colorado, 1915. 





Calyx spray. 



Cover sprays-first brood. Cover sprays-second and third 



[ 



Number of 

 plat. 



A. 



B. 



c. 



D. 



E. F. 



1 



G. 



Petals off, 

 May 5-7. 



3 to 4 



weeks 



after A, 



May 24r-26. 



21 to 22 



davs 



after B,- 



June 14-15. 



14 days 

 after C, 

 June 28. 



10 to 11 



weeks 



after A, 



July 1&-17. 



21 to 24 



days 



after E, 



Aug. 6-9. 



22 days 

 after F, 

 Aug. 2S. 



I 



First 



do 



Second 



...do 



Third. 





Fourth.. Fifth.. 1 



II 



...do 







...do 



...do 1 



.Sixth 1 



Ill 



. . .do... . 



.do 



...do 



Fourth.. .' Fifth.. 



IV 



do 



...do 



...do 





Fourth Fifth.. 1 .«!iTt.h. 



V 



. . .do.. . 



.do 



...do 





.do 



Fifth 1 



...do 1 



...do 



.do 1 



VI 



do 



...do 



...do 



l...do 



VII 



. . .do .. 



.do 



...do 



' .do. .. . 



VIII 



do 



...do 



...do 



...do 



IX 



.do.. 



.do 



...do 



.do. 



X 



Check 





















1 i 



T.\BLE 3. 



-Treatment of plats for the codling moth, Johnson orchard, Grand Valley of 

 Colorado, 1915. 



Number 



Spray materials. 



Pressure. 



Spraying equipment. 



of plat. 



Calyx spray. 



Cover sprays. 



I 



Arsenate of lead, paste, 2 pounds— 50 . . . 

 do 



Pounds. 

 200-225 

 200-225 

 200-225 

 2(K)-225 

 200-225 

 90 

 200-225 



200-225 



200-225 







II 



do i)o. 



Ill 



do 



do Tin. 



IV 



do 



do 



do 



Vermorel nozzles. . 



Bordeaux nozzles. 



-do 



Do. 



V 



do 



Do 



VI 



do 





vn 



VIII 



Arsenate of lime, homemade, 2 



pounds — 50. 

 Arsenate of lime, commercial powder, 



? pound — 50. 

 Arsenate of lead, paste, 2 pounds— 50. . 



Wliirlpool-disk nozzles. 

 Do. 



IX 



do 



Do. 



X 

















The results of these experiments will be found in Table 4, by 

 reference to which it will be seen that plats I, II, and IX, the treat- 

 ments of which were alike, produced from 52.88 to 68.41 per cent of 

 fruit free from worms. Under the varying conditions that exist in 

 most orchards, such as unevenness of insect infestation, likelihood of 

 moth migration, differences among the trees in the crop 3'ield, and 

 other contributing factors, uniform results can not alwaj^s be obtained. 

 Because of these conditions in commercial orchards one section fre- 

 quently is wormier than another, although the treatment is uniform 



• For method of preparation see U. S. Dept. Agr. Bui. 278, Miscellaneous Insecticide Investigations, by 

 E. W. Scott and E. H. Siegler. 



