18 BULLETIN 564, U. S. DEPARTMENT OF AGRICULTURE. 



of the bolls in check 2 never opened, as they rotted while covered 

 with the dense foliar growth. Thus it is seen that the detrimental 

 effect of the shaking on the fruiting of plat 6 was offset by the reduced 

 vegetative growth (due to this same shaking), allowing a greater 

 proportion of the bolls to open safely, and thus actually yielding 

 more cotton than check 2, although check 2 set more bolls than plat 6. 

 However, in a normal season this rank growth and the accompanying 

 boll rot would not be encountered, and consequently somewhat 

 different results would undoubtedly be secured. 



In order to avoid repetition the summary of this series of studies 

 is included in the general discussion at the end of the present report. 



PLAT TESTS OF THE VALUE OF THE BAG-AND-HOOP AS A MEANS OF 

 WEEVIL CONTROL UNDER FIELD CONDITIONS. 



During the season of 1916 two- series of tests were conducted to 

 determine the value of the bag-and-hoop as a means of weevil con- 

 trol on the plantation. One of these tests was conducted on Hecla 

 plantation at Mound, La., and consisted of a study of five pickings 

 at weekly intervals on Express cotton. The principal idea of this 

 test wag to secure data on this variety of cotton, as all of the earlier 

 work had been with the Simpkins variety and no records had been 

 secured on the result of using the bag-and-hoop on a long-staple 

 cotton. It was expected that there would be some difference in 

 results between the long and short staple cottons, especially in the 

 number of forms collected during the pickings. The long-staple 

 cottons generally tend to retain the infested forms longer than do the 

 short varieties, and, consequently, it seemed probable that a different 

 proportion of the infested forms would be gathered while shaking the 

 staple cotton. 



The second test was conducted on Eureka plantation and con- 

 sisted of a study of varying numbers of pickings at different time 

 intervals on Simpkins cotton. This test is referred to as Eureka 

 test No. 1 in order to distinguish it from the studies just described. 



EXPERIMENT ON HECLA PLANTATION. 



For conducting this test on Hecla plantation a small cut of cotton 

 some 4 acres in extent was selected. This cut was comparatively 

 new land, which had been in corn for several years and immediately 

 adjoined heavy timber. The cotton immediately adjoining the woods 

 consisted of a number of irregular short rows, and these were omitted 

 from the plat, the first row of the plat proper being the third row, 

 which extended completely through the cut. However, in order to 

 protect the picked plat from an influx of weevils, these short rows 

 of cotton between this plat and the timber were picked over every 

 time the plat was picked, and in the same manner the ends of the 



