1925 - Marcovitch, S. Non-arsenicals for chewing insects. J. Econ. Ent. 18(1):122. 



Sodium fluosilicate, undiluted, was effective in cage tests against the cotton 

 boll weevil. 



1925 - Nickels, C. B. Poisoning the boll weevil in the Piedmont Section of South Caro- 

 lina. S.C. Agr. Expt. Sta. C. 33, 39 p., 8 fig. Feb. Clemson. 



The cotton boll 'weevil as it occurs in South Carolina where, since its intro- 

 duction in 1917, it has become the most serious pest of cotton. Many experi- 

 ments in poisoning are described. The damage done in different seasons is very 

 variable, amounting sometimes to 75% of the crop. The loss depends upon many 

 factors; early maturing varieties are, as a rule, less subject to injury than later 

 ones. When weevils are not particularly abundant, it is frequently difficult to 

 decide whether poisoning is worthwhile. As a general rule it is considered that 

 if the crop promises to yield as much as 1/3 of a bale to the acre, and severe 

 infestation is noticed before maturity of the crop, a satisfactory profit would be 

 derived from applications of calcium arsenate dust. These applications should 

 begin as soon as boll weevil injury is observed on as many as 10% of the squares 

 and should be continued as long as new squares are being developed. 



1925 - Starr, S. H. Boll weevil control tests. Ga. Coastal Plain Agr. Expt. Sta. 5th 

 Ann. Rpt. 1924, B. 5:19-21. June. Tifton. 



Owing to the hot dry season of 1924, which exerted considerable natural con- 

 trol over the boll weevil, the increase in crop resulting from the use of insecti- 

 cides was not so great as in the previous year, which was wet. Very good results 

 have, however, been obtained by applying with a hand mop a syrup consisting of 

 3 lbs. calcium arsenate, 1 U.S. gal. molasses, and 3 U.S. gal. water to the grow- 

 ing points of the cotton plants 7 to 10 days before the first squares appear, 

 repeating the treatment 2 or 3 times at weekly intervals, and subsequently dust- 

 ing with calcium arsenate. The syrup would probably be more effective with an 

 increased proportion of molasses, if this did not add too much to the cost. 



1925 - Youngblood, Bonney. Entomology. Tex. Agr. Expt. Sta. 1924-25 Rpt. 38:19-24. 



Col. Sta. 



"Cotton boll weevils . . . that emerged from hibernation in the spring were 

 observed in connection with the ingestion of poison. The insects never groom 

 themselves with their rostrum, but use their legs for the purpose. When a weevil 

 moves about on glass or leaves that have been dusted with poison, the tip of its 

 rostrum quickly becomes covered with dust, and particles of dust may be picked 

 up by the mandibles, which work continually; even if it is well fed, paralysis and 

 death occur in 3 to 8 hours. In cages where entire plants were dusted, 27% of the 

 weevils were killed in 24 hours, and 88% in 5 days. In cages in which the squares 

 and bolls were enclosed in paper bags before the plants were dusted, 13% and 52% 

 of the weevils were killed in 1 and 5 days, respectively." 



1926 - Hinds, W. E. Progress in cotton boll weevil control. J. Econ. Ent. 19(1): 1 12-121. 



In the cotton belt of the United States, the loss in cotton yield due to the 

 cotton boll weevil in the past has averaged from 20% to 40% of the normal pro- 

 duction, representing a very large increase in the cost to the consumer. As a 

 result of concerted action by all parties concerned, however, and owing to the 

 establishment of a safe and dependable program for cotton production and weevil 

 control, a permanent system of agriculture for the cotton belt is now being fol- 

 lowed, involving the continued production of cotton on a more economic basis, 

 insurance of a fair profit to the grower, and more reasonable prices of cotton 

 products for the consumer. Dusting by aeroplanes has given excellent results in 

 trials and will probably become an important method of control in the near 

 future. 



Aphis gossypii, which is frequently very abundant, can be controlled at the 

 same time as the boll weevil by adding to the calcium arsenate dust nicotine 

 sulfate in the proportion of 94 parts (weight) of calcium arsenate with 6 parts 

 nicotine sulfate (40%), that is, practically 1 lb. calcium arsenate to 1 oz. nicotine 

 sulfate. Over 98% of the aphids are destroyed by an application of 8 - 9 lbs. of 

 the dust per acre. 



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