1926 - Robinson, J. M. Dusting cotton with calcium arsenate for boll weevil control 

 (P. R.). Ala. P. I. Agr. Expt. Sta. C. 51, 12 p., 3 fig. May. Auburn. 



Details of tests made in 1924 and 1925 for the control of the cotton boll 

 weevil in Alabama. The preliminary tests in 1924 gave sufficient evidence to 

 show the superior value of calcium arsenate dust over the sweetened poison, 

 so that all further tests should begin when the infestation reaches 10%. Three 

 applications made at intervals of 4 to 5 days should be sufficient. An application 

 just before the cotton begins to square is advisable when there are 20 or more 

 weevils per acre. The infestation can be determined by counting all the squares 

 on the plants until 100 is reached; the number of punctured squares among these 

 will give the percentage of infestation. If infestation is below 10%, there is little 

 or no advantage in dusting. About 6 lbs. calcium arsenate to an acre are required 

 for 1 application. 



Average increases in yields from dusting in 1924 was 204 lbs. of seed cotton 

 per acre. Average cost of dusting per acre was $5.00. Thirty-six pounds of cal- 

 cium arsenate is enough for dusting 6 times. 



1926 - Sanborn, C. E. Boll weevil inOklahoma, especially during the years 1921 to 1925. 



Oklahoma Agr. Expt. Sta. B. 157, 32 p., 10 pi., 4 fig. Feb. Stillwater. 



A good deal of the information contained in this bulletin on the cotton boll 

 weevil was given in a previous circular. Later tests have proved that dusting 

 with calcium arsenate is not a satisfactory method of control in Oklahoma. The 

 profit accruing from the use of the various methods has been worked out and is 

 shown in tabular form. The materials tested included molasses -arsenate, nico- 

 tine-sulphate and calcium-arsenate, Hill's mixture, and poisoning by the Florida 

 Method. For Oklahoma conditions, the best is the molasses -arsenate, consisting 

 of 1 U.S. gal. of good table brand of syrup, 1 U.S. gal. water, and 1 lb. calcium 

 arsenate, thoroughly mixed and used fresh, and splashed onto the plants with a 

 mop. About 1 U.S. gal. of this mixture to the acre was used at each application, 

 the treatments being given at intervals of about 7 to 10 days, beginning after in- 

 festation reached 10% to 15%. 



1927 - Anonymous. Entomology. Tex. Agr. Expt. Sta., 1926 Rpt. 39:28-31. Col. Sta. 



In order to study the ingestion of poison by the cotton boll weevil, field ap- 

 plications of calcium arsenate dust were made to cotton in the morning when a 

 heavy dew was present, using 10 lbs. an acre. Analysis of the dusted buds and of 

 430 boll weevils killed by the poison showed that it would be necessary for a 

 weevil to devour all the poison present on a bud or equivalent surface to obtain 

 a fatal dose. The indications are that weevils obtain the greater part of the poi- 

 son that kills them by the adherence of small particles of dust as they travel over 

 the plant, and that 60% of them die from poison so obtained. The degree of mor- 

 tality of weevils on hairy varieties of cotton is, therefore, to be compared ex- 

 perimentally with that obtained under similar conditions, upon less hairy ones. 



"As a test of the efficacy of aeroplane dusting for Anthonomous grandis , 

 11,200 lbs. of calcium arsenate were distributed in 3 applications at an average 

 rate of a little more than 9-1/2 lbs. an acre for each application. The yields are 

 not yet complete, but the indications are that the poison used was effective in 

 reducing damage by the boll weevil." 



1927 - Anonymous. Las plagas del altodonero (Pests of the cotton plant). Mex. Sec. 



Agr. y Fomento. Mens. Defensa Agr. B. l(2):70-84, 1 map. June. 5. Jacinto, D. F. 

 Anthonomus grandis Boh., as cotton pest of many years' standing in Mexico, 

 now appears to be satisfactorily controlled by the dusting of calcium arsenate 

 from aeroplanes. 



1927 - Folsom, J. W. Calcium arsenate as a cause of aphis infestation. J. Econ. Ent. 

 20(6):840-843. 



In dusting with calcium arsenate for the control of the cotton boll weevil in 

 Louisiana, it was observed that excessive applications of this dust were often 

 followed by heavy infestation of Aphis gossypii Glov. Experiments to discover the 



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