CONTROL OF BOLL WEEVIL IN MISSISSIPPI DELTA. 



31 



the various plats, it is seen that only 85 weevils were secured from 

 plat 4, while 90 were picked from plat 3. The high number secured 

 at the sixth picking brought the total for plat 2 up to 661. 



The forms collected in the bags from the different plats at the 

 various pickings are shown in Table 26. 



Table 26. — Forms collected per acre with bag-and-hcop, Eureka plantation, Tallulah, 

 La., 1916, experiment No. 1. 





Date. 



Forms collected. 



Clean. 



Punc- 

 tured. 



Plat No. 



Total. 



Clean. 



Punc- 

 tured. 





( June 13 



123 

 116 

 338 

 472 

 1,309 

 2,196 



48 

 43 

 159 

 271 

 990 

 419 



75 



73 



179 



201 



319 



1,777 



Per cent. 

 39.0 

 37.1 

 47.0 

 57.4 

 75.6 

 19.1 



Per cent. 

 61.0 





June 20 



62.9 







53.0 





July 5 



42.6 



2.. ... 



July 11 



24.4 





July 22 



80.9 





Total 







4,554 



1,930 



2,624 











42.4 



57.6 





(June 13 











108 

 156 

 127 

 83 

 231 

 223 



33 



68 

 43. 

 • 42 

 105 

 109 



75 

 88 

 84 

 41 

 123 

 114 



30.6 

 43.6 

 33.9 

 50.6 

 45.5 

 48.9 



69.4 





June 17 



56.4 





June 20 



66.1 





June 23 



49.4 



3 



June 27 







June 30 



51.1 





Total 







928 



400 



528 









Weighted average 



43.1 



56.9 



t 



( June 13 













76 



98 



223 



330 



28 

 25 

 99 

 224 



48 

 73 

 124 

 106 



36.8 

 25. 5 

 44.4 

 67.9 



63.2 





June 20 



74.5 







55.6 



4.. 



July 5 



32.1 





Total 







727 



376 



351 









Weighted average 



51.7 



48.3 















One interesting feature of the figures shown in Table 26 is the ex- 

 tremely rapid increase in the number of forms collected at the later 

 pickings. For example, in plat 2, 2,196 forms were collected at the 

 sixth picking, while a total of only 2,358 were collected at the other 

 five pickings from this plat. Another important feature is the high 

 percentage of clean forms collected in the bags. This varied from 

 42.4 to 51.7 in the different plats and averaged 45.7 over the entire 

 series. From this it is seen that almost one-half of the total forms 

 collected in the bag-and-hoop during this series of tests were per- 

 fectly clean. In addition to this destruction of clean squares the 

 same loss of terminal buds which was noted in the other tests was 

 observed in this experiment. 



It is interesting to compare the form collections of plat 2 with those 

 made on the Hecla test about the same time. This comparison is 

 shown in Table 27. 



