40 BULLETIN 564, IT. S. DEPARTMENT OF AGRICULTURE. 



Table 34. — Fallen form collections in machine-picked test, Tallulah, La., 1916. 





Picked plal 



. 



Check plat 





Date. 



Squares. 



Bolls. 



Total 

 forms. 



Squares. 



Bolls. 



Total 

 forms. 



July 27 



1,385 

 i,436 



516 

 372 



1,901 



1,808 



1,371 

 2,581 



805 

 984 



2,176 



3 565 









Total 



2,821 



888 



3,709 



3,952 



1 789 



5,741 







From this table it is seen that on both occasions considerably more 

 forms were gathered from the ground in the check plat than in the 

 picked plat. In the two pickings a total of 3,709 fallen forms were 

 gathered from the picked plat and 5,741 from the check, thus giving 

 a reduction of 2,032 in favor of the picked plat. 



INFESTATION. 



The degree of weevil infestation in the two plats was followed 

 through the season in the usual manner in order to determine the 

 effect of the picking operations. Table 35 gives the results of these 

 observations. 



Table 35. — Square infestation, Tallulah, La., 1916. 



Date. 



Picked 

 plat. 



Check 

 plat. 



Julyl. 

 July 7. 

 July 13 

 July 21 

 July 27 

 Aug. 2. 

 Aug. 8. 



Per cent. 

 14.3 

 21.4 



47.7 

 60.3 

 66.8 

 85.3 



88.8 



Per cent. 

 14.3 

 17.2 

 38.0 

 57.2 

 75.0 

 85.3 

 90.3 



From this it is seen that at the beginning of the experiment the 

 two plats averaged exactly the same infestation. At the next exam- 

 ination, however, the picked plat increased slightly above the check 

 plat and retained this position until July 27. The seasonal average 

 of the check plat was 53.9 per cent, while that of the picked plat was 

 54.9 per cent. Thus these records fail to show any decrease in the 

 infestation due to the weevil collections. In fact, the averages are 

 remarkably nearly equal. Studies on the seasonal average infestation 

 of the various points of observation show this infestation to have 

 been evenly distributed in the various, plats. 



effect on plants. 



The plant breakage due to the operation of the machine has been 

 mentioned. By the latter part of the season it was quite obvious 

 that this was going to have a very detrimental effect on the picked 

 plat. The picked cotton looked as if it had been topped, and it was 



