increases, although the latter did reduce populations after each application. Ap- 

 parently yields were reduced slightly in plots receiving these early applications 

 at the time plants were in the 4 to 8 leaf stage. Calcium arsenate -sulphur and the 

 BHC -DDT -sulphur controlled fleahoppers, the latter being more effective. Yields 

 from late season control with 6 treatments of calcium arsenate or BHC-DDT- 

 sulphur were practically equal to those on plots receiving from 2 to 5 additional 

 dustings earlier in the season. The BHC -DDT -sulphur mixture was faster acting 

 than the calcium arsenate. The results indicate that it is more profitable to dust 

 cotton the last 3 weeks of July and August with a quick acting mixture. 



1948 - Gaines, R. C., and M. T. Young. Benzene hexachloride mixtures to control four 

 cotton insects. J. Econ. Ent. 41(l):l9-22. 



Satisfactory control of the boll weevil was not obtained in this experiment. 

 Only 2 treatments which caused a significant increase in yield over the check 

 were with calcium arsenate and the 5.75% gamma benzene hexachloride. 



In laboratory tests, vapors given off by benzene hexachloride killed boll 

 weevils. Red spiders were more numerous on cotton which had been dusted 

 several times with benzene hexachloride than on cotton dusted with other insec- 

 ticides or an untreated cotton. Benzene hexachloride, when applied to cotton, 

 killed many beneficial insects. 



The results of these experiments indicate that benzene hexachloride should 

 not be mixed with regular calcium arsenate. 



1948 - Kulash, Walter M. New insecticides for cotton insect control. J. Econ. Ent. 

 41(6):986-987. 



Field tests for control of cotton boll weevil and bollworm were conducted in 

 small replicated plots in a field near Raleigh, N.C. Dust treatments were made 

 with (1) 20 percent chlorinated camphene, (2) a combination dust of 3% gamma 

 benzene hexachloride and 5% chlordan. Untreated checks consisted of (1) random- 

 ized check plots located in randomized blocks of the treatment area, (2) a center 

 strip of checkplots dividing the treatment area into 2 pairs of randomized blocks. 



Five dust applications were made from July 22 to August 29. Each applica- 

 tion received 10 pounds of dust per acre applied with a rotarytype hand gun. 

 Lowest average weevil infestation at the end of the season was recorded for the 

 5% gamma benzene hexachloride treatment. The highest yield, based on total 

 picking of seed cotton in 2 center rows of plots 10 rows wide by 75 feet long, 

 was recorded in the 20% chlorinated camphene treatment. 



1948 - Loden, Harold D., and Horace O. Lund. Chlorinated camphene and parathion 

 to control the cotton boll weevil and cotton aphid. J. Econ. Ent. 41 (6) :85 1 -853. 



Chlorinated camphene and parathion dusts were tested against the cotton 

 boll weevil and the cotton aphid in small-plot field experiments. Chlorinated 

 camphene appears to maintain a residual killing power for the boll weevil for 

 over 3 weeks, but neither chlorinated camphene nor parathion appears to exert 

 any significant residual killing power against cotton aphids after 1 week. Regular 

 weekly applications of calcium arsenate and chlorinated camphene appear to be 

 about equal in their final effect upon the boll weevil populations, but the chlori- 

 nated camphene effects the control more rapidly. Parathion in the 1% concentra- 

 tion is not effective against the boll weevil. Yields of the plots treated weekly for 

 6 weeks with chlorinated camphene were statistically superior to all others ex- 

 cept the calcium arsenate plots, but the calcium arsenate plots were not signifi- 

 cantly superior to any others. 



1948 - Scales, A. L. , and G. L. Smith. Cage tests against the boll weevil and the tar- 

 nished plant bug with synthetic organic insecticides and calcium arsenate in 1947. 

 J. Econ. Ent. 41(3):403. 



Against the boll weevil, with the exception of 5% DDT, all the organic insec- 

 ticides, parathion (0.5%-2%), chlordan (5%-20%), toxaphene (5%-20%), and BHC 

 (1.25%-5% gamma), and mixtures of these insecticides were equal in effective- 

 ness to calcium arsenate. Against the boll weevil, 20% of chlordan, a mixture of 

 10% of chlordan and 5% of DDT, and calcium arsenate gave the highest net mor- 

 talities, and all were equally effective. 



45 



