Toxaphene spray gave significantly less control of the boll weevil but as good 

 control of the bollworm as special calcium arsenate -1% gamma benzene hexachlo- 

 ride under light infestations of weevil and moderate bollworm infestations. Ten 

 percent chlordane-5% DDT, 3% gamma benzene hexachloride-5% DDT, and 20% 

 toxaphene as dusts gave significantly better control of the bollworm than toxa- 

 phene spray or special calcium arsenate- 1% gamma benzene hexachloride dust. 

 Ten percent chlordane-5% DDT dust effected a significantly better yield of cotton 

 than did toxaphene spray. 



Toxaphene spray and toxaphene dust were equally effective against boll 

 weevils and bollworms under light infestations of weevil and heavy bollworm 

 infestations. Toxaphene-DDT spray gave better control of these insects than 

 toxaphene spray or dust. 



1950 - Dunnam, E. W., and S. L, Calhoun. Artificial defoliation of cotton and boll weevil 

 control. J. Econ. Ent. 43(4) :488-490. 



Studies made at Stoneville, Miss., to determine the response of the adult boll 

 weevil to the defoliating action of calcium cyanamide on cotton plants, and the 

 value of this practice as a weevil control measure. Defoliation of cotton caused 

 an almost immediate exodus of weevils to untreated fields. When cotton was 

 treated as early as August 23, the boll weevil did not reach maturity in any sec- 

 ond growth forms before frost on November 1. Removal of leaves, squares, and 

 young bolls artificially checked plant growth, accelerated opening of bolls, and 

 made an earlier harvest possible. Under these conditions cotton stalks can be 

 destroyed earlier in the season, thereby offering a supplement to the regular 

 campaign to destroy the cotton stalks as a boll weevil control measure, or a 

 substitute for destroying stalks. 



Defoliation is practiced extensively in the Mississippi Delta as an aid to 

 mechanical harvesting, but it is also very beneficial for boll weevil control. 



1950 - Fenton, F. A. Spraying and dusting for cotton insect control. J. Econ. Ent. 

 43(3):292-294. 



Spraying cotton by plane or with a low-gallonage sprayer operated at from 

 60 to 80 psi, with an emulsion containing toxaphene and DDT, produced good con- 

 trol of boll weevils and bollworms. The average amount of toxaphene applied 

 varied from 1.5 to 1.8 pounds per acre per application; DDT, 0.75 to 0.9 pounds. 

 Comparative counts of infestations and yields showed that control was as good as 

 was obtained with several dust formulations recommended for boll weevil con- 

 trol. 



1950 - Fife, L. C., R. L. Walker, Jr., and C. E. Jernigan. Low-gallonage emulsion 

 sprays gave effective boll weevil control. S.C. Agr. Expt. Sta. Rpt. 63:95-96. 

 Dec. Clemson. 



Extensive tests were conducted to compare low-gallonage emulsion sprays 

 with dusts for control of the boll weevil. Sprayed and dusted plots of about 0.5 

 acre each were adjacent to each other, so that the results were directly com- 

 parable. All treatments were replicated in 3 fields. 



All the plots were dusted or sprayed the same number of times and on the 

 same dates. The number of applications ranged from 10 to 12 for the different 

 fields, and applications were made at 5- to 7 -day intervals, beginning when the 

 first fruiting forms were noted. 



Spraying or dusting gave equal control of the boll weevil. With the possible 

 exception of plots treated with aldrin, in which dust proved better than the spray, 

 yields from comparable plots were about the same for both methods. Excellent 

 boll weevil control was obtained with all insecticides tested; the increase in 

 yield averaged about 1,000 pounds of seed cotton per acre. 



1950 - Fife, L. C., R. L. Walker, Jr., and C. E. Jernigan. Tobacco sprayers can be 

 used for applying wettable -powder sprays for cotton insect control. S.C. Agr. 

 Expt. Sta. Rpt. 63:97. Dec. Clemson. 



Sprays made from wettable powders of toxaphene, chlordane, and BHC plus 

 DDT were applied with the regular 2-row tobacco sprayer for boll weevil control. 



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