rapid plant bug than the commercial calcium arsenate. This poison gave a higher 

 control of the boll weevil and a higher yield than the commercial calcium arsen- 

 ate, but the differences were not significant. Calcium arsenate gave significantly- 

 better control of weevils than cryolite, but, under dry weather conditions which 

 caused excessive shedding, this difference did not affect the yields. In a prelimi- 

 nary test sulfur -calcium arsenate mixture (2 to 1) applied at the rate of 15 lbs. 

 per acre gave 89%, 39%, and 61% control of the flea hopper, rapid plant bug, and 

 boll weevil, respectively. 



1940 - Gaines, R. C. Insect pests and their control. La. Agr. Expt. Sta. B. 323, 51 p. 



Tests in Louisiana confirm the view that an adequate number of applications 

 of calcium arsenate dust remains the best method of controlling the boll weevil. 



1940 - Gaines, R. C. Boll weevil control with calcium arsenates containing different 

 percentages of water-soluble arsenic pentoxide. J. Econ. Ent. 33(4) :682-684. 



Calcium arsenates containing low, intermediate, and high percentages of 

 water-soluble arsenic pentoxide by the New York method were tested against the 

 boll weevil at 8 localities in 1938 and at 5 localities in 1939. The tests included 

 68 replications. 



The average infestation during 1938 and 1939 in the plots treated with low 

 was 18.9%, intermediate 17.6%, high 17.2%, and untreated checks 34.7%. The 

 average yield in 1/60 -acre plots treated with low was 24.1 lbs. per plot, inter- 

 mediate 23.2 lbs., high 23.3 lbs., and untreated checks 19.6 lbs. 



The differences between the infestations and the yields in the calcium ar- 

 senate -treated plots each differed significantly at the 1% level from the infesta- 

 tion and yield in the untreated checks, but there were no significant differences 

 among the infestations and yields in the plots treated with the calcium arsenates 

 containing low, intermediate, and high percentages of water-soluble arsenic 

 pentoxide. 



1940 - Gaines, R. C., M. T. Young, and G. L. Smith. Effect of insecticides used in boll 

 weevil control upon aphids and mirids. J. Econ. Ent. 33(5):792-796. 



Aphids usually increased in number following application of calcium arsen- 

 ate. A larger number of aphids was found in plots treated with calcium arsenate 

 containing 10.3% of water-soluble arsenic pentoxide by the New York method 

 than in plots treated with calcium arsenate containing 0.5%, the number found in 

 plots treated with calcium arsenate containing 4.6% falling between the other 2. 

 Sulphur appeared to have little or no effect upon aphid infestations. 



There was a definite correlation between aphid infestations and yields and 

 between aphid infestations and effectiveness of insecticides against boll weevils 

 in cages. The reduction in yields caused by aphids is of much importance. In 1 

 series of tests calcium arsenate was sufficiently effective to control light infes- 

 tations of the tarnished plant bug and the rapid plant bug without the addition of 

 sulphur to the dusting mixture. 



1940 



- McGarr, R. L. Progress report (1939) on mixtures of calcium arsenate and 

 sulfur for control of the boll weevil at State College, Mississippi. Assoc. South. 

 Agr. Workers Proc., 41:114. 



Dusting with mixtures of equal parts of calcium arsenate and sulfur, or of 1 

 part calcium arsenate to 2 parts sulfur, was as satisfactory for boll weevil control 

 as dusting with straight calcium arsenate. 



1940 - Rainwater, C. F., and F. F. Bondy. Combination of insecticides for boll weevil 

 and cotton leaf aphid control. Assoc. South. Agr. Workers Proc., 41:114. 



Experiments were conducted near Florence, South Carolina, during 1939 to 

 determine the effect of several combinations of insecticides on the control of the 

 boll weevil and cotton leaf aphid, Aphis gossypii Glov. Calcium arsenate was 

 combined with the following insecticides and diluents: (1) equal parts of nicotine 

 bentonite, (2) equal parts of nicotine bentonite-tannate, (3) equal parts of sulfur to 

 which 0.5% rotenone from derris was added, and (4) equal parts of Celite to which 



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