or water, over a period of several days. However, such a condition does not occur 

 in cotton fields. 



4. When boll weevils had access to food in the form of nonpoisoned cotton 

 squares and, at the same time, to dew from treated plants, no mortality resulted. 

 This showed that the weevil can be poisoned under normal conditions only by 

 poisoned food. 



1920 - Warren, D. C. Dusting cotton for the control of boll weevil. Ga. Sta. Bd. Ent. 



B. 56, 15 p., 2 fig. Feb. Atlanta. 



While a considerable amount of experimental work has been done in various 

 parts of the United States in dusting cotton for the cotton boll weevil, it was 

 essential that special tests be made in Georgia. Particulars are given of the 

 experiments and the results show that the method was successful in practically 

 every case. Directions are given for applying poison; the various materials that 

 may be used, of which calcium arsenate gave the best results; the dosage and 

 number of applications; and suitable machinery. 



1921 - Brown, H. B., and J. F. O'Kelley. Cotton experiments. Miss. Agr. Expt. Sta. 



B. 205, 15 p., 2 fig. Dec. 



Boll weevils appeared in the college cotton fields in Mississippi as early as 

 June 13, 1921. On June 24 ordinary calcium arsenate dust spray was applied, but 

 there was hardly sufficient dew to make it successful. This poison was afterwards 

 applied in a water solution. A further mixture was made of 1 lb. calcium arse- 

 nate, 1 U.S. gal. blackstrap molasses, and 1 U.S. gal. water. The latter was more 

 expensive and troublesome to handle than the former, but seemed to adhere better 

 and was sometimes visible when showers had washed off the other poisons. 



1921 - Coad, B. R. Killing boll weevils with poison dust. U. S. D. A. Ybk 1920:241-252, 

 2 fig. 



These experiments proved that the cotton boll weevil can be controlled by 

 calcium arsenate dust. Experiments with this poison were extensive in 1920, and 

 the reasons for their success and failure are discussed. 



1921 - Coad, B. R., and T. P. Cassidy. Some rules for poisoning the cotton boll weevil. 

 U. S. D A. C. 162, 4 p. Jan. Wash. 



Briefly states the information needed by farmers when considering the ad- 

 visability of poisoning the cotton boll weevil and the best means of doing it. 



1921 - De La Barreda, L. El arseniato do calcio contra el Picuda del Algodonero. 



(calcium arsenate against Anthonomus grandis Boh). Rev. Agr. 11:770-774, 9 

 fig. Mar. San Jacinto, D. F. 



The information given in this article is on the use of calcium arsenate 

 against the cotton boll weevil. 



1921 - Howard, L. O. Report of the Chief of the Bureau of Entomology and Plant Quar- 

 antine, 1920-21. U. S. D. A., 33 p. Aug. 1. Wash. 



"Among Southern crop pests the cotton boll weevil . . . was treated by 

 dusting with dry powdered calcium arsenate on a large scale, 75,000 acres of 

 cotton being dealt with. A brief summary of rules for poisoning has been issued, 

 and is widely used by farmers." 



1921 - Parrott, P. J. The seasons experience with insects and insecticides. N.Y. State 

 Hort. Soc. Proc. 66:17-37. Rochester. 



"Hitherto, calcium arsenate has been chiefly used against the cotton boll 

 weevil . . . for which purpose about 10 million pounds were allotted to the 

 Southern States during 1920." 



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