THE FRUIT-TREE LEAF-ROLLER. 



103 



EXPERIMENTAL TESTS FOR THE DESTRUCTION OF THE EGGS. 



Many laboratory tests were made for the destruction of the eggs. 

 Only egg masses deposited on twigs were used, and these twigs were 

 dipped in the various mixtures employed. After treatment the 

 masses were kept hi separate jars. The results of the test are shown 

 in Table IIT. 



Table III. — Tests of sprays for the destruction of eggs of the fruit-tree leaf-roller. 



No. 

 of 

 ex- 

 peri- 

 ment. 



Material used. 



Date of 

 applica- 

 tion, 1912. 



Number 



of egg 



masses 



treated. 



Number 



of egg 



masses 



un- 



hatched. 



Number 



of egg 



masses 



hatched. 



Remarks. 



1 



Miscibleoil (1:12) 



Jan. 3 



10 



10 









2 



Miscible oil (1:15) 



...do.... 



10 



10 









3 



Miscible oil (1 :20) 



do . 



10 



10 







4 



Miscible oil (1 : 10) 



.do ... 



5 



5 







5 



25 per cent kerosene emul- 



...do.... 



10 



9 



r 



3 eggs in mass hatched. 



6 



20 per cent kerosene emul- 

 sion. 

 25 per cent crude petro- 



...do.... 



10 



10 









7 



...do.... 



5 



5 











leum emulsion. 













8 



20 per cent crude petro- 

 leum emulsion. 



...do.... 



5 



4 



1 



12 eggs in mass hatched. 



9 



8 per cent distillate-oil 

 emulsion. 



...do.... 



5 



5 









10 



5 per cent distillate-oil 

 emulsion. 



...do.... 



5 







5 



Most all the eggs hatched. 



11 



Commercial lime-sulphur 



(1:8). 

 Commercial lime-sulphur 



...do. . . . 



10 







10 



Practically all eggs hatched . 



12 



...do.... 



5 







5 



Do. 





(1:9). 













13 



Commercial lime-sulphur 

 (1:10). 



Commercial lime-sulphur 



...do.... 



5 







5 



Do. 



14 



...do.... 



5 







5 



Do. 





(1:11). 













15 



Commercial lime-sulphur 



(1:12). 

 Check— untreated (caged) . 



...do.... 



5 







5 



Do. 



16 



...do.... 



5 







5 



All egg masses hatched well. 



17 



Miscible oil (1 : 12) 



Mar. 5 



15 



15 









18 



Miscible oil (1 : 15) 



...do.... 



15 



14 



1 



Only 1 egg hatched. 



19 



Miscible oil (1:18) 



...do.... 



15 



15 









20 



25 per cent kerosene emul- 

 sion. 



20 per cent kerosene emul- 

 sion. 



25 per cent crude petro- 



...do.... 



10 



10 









21 



...do.... 



10 



9 



1 



6 eggs in mass hatched. 



22 



...do.... 



9 



7 



2 



7 eggs in 2 masses hatched. 





leum emulsion. 













23 



10 per cent distillate-oil 

 emulsion. 



...do... 



10 



10 









24 



Check— imtreated (caged) . 



...do.... 



10 







10 



All eggs hatched well. 



25 



Miscibleoil (1:12) 



Apr. 14 



86 



84 



2 



1 egg in each mass hatched . 



26 



Miscible oil (1 : 15) 



...do.... 



122 



119 



3 



7 eggs in 1 mass hatched; about 

 one-fourth total eggs in 2 

 masses hatched. 



27 



Whitewash 



...do.... 



25 







25 



Practically all eggs hatched. 



28 



Check— untreated (caged). 



...do.... 



113 







113 



107 masses hatched well; about 

 one-half total eggs hatched in 

 6 masses. 



It will be noted that the miscible oil ranging in strength from 1 :10 

 to 1:20 gave the best results. The crude-petroleum kerosene and 

 10 per cent distillate-oil emulsions ranked second in effectiveness. 

 Commercial lime-sulphur solution was found to be ineffective, as was 

 whitewash. 



