1929 - Wallace, H. F. Boll weevil and plant lice poisoning work. Miss. Agr. Expt. Sta. 



B. 271:14-15. 



In 1929, experiments were carried out in Mississippi to test the advisability 

 of dusting cotton late in the season, for the control of the boll weevil and aphids. 

 The dusts were applied on August 9, when the weevil infestation on all plots 

 reached 100%, and again on the 16th of August at the rate of 14 lbs. per acre. Two 

 dusts were used; one, a mixture of 8 parts calcium arsenate to one part tobacco 

 dust. The dust containing nicotine sulphate resulted in an increased yield of 355 

 lbs. per acre over the untreated plots, and that containing tobacco dust, 259 lbs. 

 Both forms of nicotine controlled aphid infestation, and the treatments resulted 

 in an increased profit equivalent to about $15 per acre. 



1930 - Anonymous. Entomology. Tex. Agr. Expt. Sta., 1928 Rpt. 41:42-49; 42d, 1929; 



pp. 41-47, 146-147. College Station. 1929-1930. 



Experiments on the relative number of boll weevils killed by the calcium 

 arsenate adhering to different parts of dusted cotton plants showed that 2.2% 

 were killed on the stems, 13.2% on the squares and bolls, and 84.6% on the 

 leaves. 



1930 - Hinds, W. E. Calcium arsenate tests, 1929, a progress report on small-scale 

 tests comparing boll weevil (Anthonomus grandis Boh.) control with Lucas' 

 green cross calcium arsenate versus a "standard brand" of calcium arsenate. 

 J. Econ. Ent. 23(4):672-676. 



These 2 forms of calcium arsenate were tested in the field in various ways. 

 The Lucas materials showed indications of some advantages in dusting qualities 

 and in adhesion to cotton in spite of rains. It appeared to be slightly more effi- 

 cient in reducing the percentage of squares attacked by the boll weevil in plots 

 dusted with this material and in the yield of cotton secured from an average of 

 the four treated plots'. In cage toxicity tests where weevils were exposed for 

 24-hour periods on dusted plants, the Lucas material gave an average mortality 

 of 58% for the 6 successive periods of 24-hour exposure while "standard brand" 

 calcium arsenate gave an average of 38%. These results were from 3 series of 

 tests. 



1930 - Robinson, J. M., and F. S. Arant. Entomology. Ala. Agr. Expt. Sta., 1929-1930 



Rpt. 41:30-32, 37. 



Studies on the control of the boll weevil with calcium arsenate were continued 

 in 1929. On the sandy loam plots the infestation was kept below 20% until the 3d of 

 September by 3 applications beginning on August 12, which resulted in an in- 

 creased yield of 46 lbs. of seed cotton per acre. On the untreated plots the infes- 

 tation had reached 95%. The average increase in yield from dusting during the 

 last 6 years was dependent on the time of planting, rate of fertilization, and the 

 percentage of infestation. The yield of seed cotton was increased 42 lbs. per acre 

 by dusting, alone, and 184 and 307 lbs. per acre with the addition of 500 and 

 2,000 lbs. of fertilizer, respectively. 



On clay plots the infestation was 38% on the 18th of June. Three applications 

 of calcium arsenate at intervals of 4 to 11 days reduced it to 20% and kept it 

 below 20% until the 15th of July. During a second series of 5 applications, two 

 of which were washed off by the rain within 24 hours, the infestation varied 

 from 6 to 36% until the 6th of August. On the 10th of August a 9th application was 

 made to protect the young bolls. On the untreated plots the infestation had 

 reached 83%. The increase in yield was 223 lbs. of seed cotton per acre, and the 

 average increase over the 6-year period was 252 lbs. 



1931 - Roark, R. C. Use of economic poisons to safeguard crops. U.S. Daily, 1 p. 



July 20. 



It is estimated that 5,000,000 U.S. gals, of petroleum oil, 30,000,000 lbs. of 

 lead arsenate, and 30,000,000 lbs. of calcium arsenate (the last-named, largely 

 against the cotton boll weevil) are used annually as insecticides. 



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