Insects were exposed in petri dishes to leaves taken from each plot immediately 

 and at 24 -hour intervals for 12 days after application. The initial kill was more 

 rapid and residues which resulted in mortality persisted longer on plants treated 

 with Bayer 17147 than on plants treated with toxaphene. 



1956 - Arant, F. S., and R. L. Robertson. Field experiments with nonsystemic insecti- 

 cides for control of cotton insects. Assoc. So. Agr. Workers Proc. 53:128. 



Replicated small-plot experiments were conducted with dusts and sprays for 

 control of cotton insects. Insecticides were applied with high-clearance tractor 

 equipment. Seven applications were required during the season. Bayer 17147 

 gave excellent control of the boll weevil at rates of 0.25, 0.37, and 0.50 pound per 

 acre. Endrin at the rate of 0.37 pound per acre gave excellent control of the boll 

 weevil and the bollworm. Several other insecticides gave satisfactory results. 



1956 - Cowan, C. B., Jr., C. R. Parencia, and J. W. Davis. Late-season control of the 

 boll weevil and the bollworm with new insecticides in 1955. J. Econ. Ent. 

 49(6):783-785. 



Small-plot and large-scale experiments with several insecticides applied as 

 dusts and as low-volume sprays were conducted in central Texas during 1955 for 

 the control of late-season infestations of the boll weevil and the bollworm, 

 Heliothis zea (Boddie). 



In several experiments, Bayer 17147 gave excellent boll weevil control at 

 0.25 and 0.375 pound per acre. In one experiment 0.125 pound of 17147 and 0.25 

 pound of Bayer 16259 were less effective. In another experiment Strobane and 

 chlorthion were less effective than toxaphene, and Bayer L 13/59 was ineffective. 

 Dieldrin at 0.43 pound per acre compared favorably in control and yield with 

 Bayer 17147 at 0.36 pound in a large-plot experiment. DDVP dusts and sprays, 

 with or without Aroclor, were ineffective at the dosages used. 



1956 - Early, Jack D., and James H. Cochran. Insecticidal evaluation of organic ar- 

 senical compounds. J. Econ. Ent. 49(2):239-242. 



Evaluation of 39 organic arsenical compounds in the laboratory for their 

 insecticidal properties, using boll weevils, rice weevils, southern armyworm 

 larvae, and cotton leafworm larvae, as test insects. Arsenated toxaphene pos- 

 sessed the highest degree of toxicity and was more effective than toxaphene 

 against the boll weevil. Several other compounds exhibited a high degree of 

 toxicity but some were phytotoxic. 



1956 - Lincoln, Charles, and T. F. Leigh. Time of day and frequency of insecticidal 

 application in relation to control of the cotton boll weevil. Assoc. So. Agr. 

 Workers Proc. 53:127. 



Midday and late afternoon applications of insecticides to control the cotton 

 boll weevil were compared in replicated plots. Daytime applications were made 

 between 9 a.m. and 5 p.m. and nighttime applications between 5 p.m. and 8 p.m. 

 Daytime applications included toxaphene dust and heptachlor granules. Applica- 

 tions at night included endrin dust and 3-5 (BHC-DDT) dust. Satisfactory control 

 was obtained with midday applications of all materials, although the efficiency of 

 BHC dust was somewhat reduced. Four-day and 7-day application frequencies 

 were tested in replicated plots using 3-5-40 (BHC-DDT-S), 2|-5-40 (heptachlor- 

 DDT-S), endrin, and calcium arsenate as dusts applied with ground equipment. 

 Satisfactory control of the cotton boll weevil was obtained with all materials and 

 at both frequencies, but some difference in degree of control was experienced. 



1956 - Mistric, W. J. Effect of sunlight and other factors on the toxicity of certain in- 

 secticides. J. Econ. Ent. 49(6):757-760. 



Laboratory experiments were conducted at College Station, Tex., during 1954 

 to determine the effects of climatic factors, insecticidal dosage levels, and mul- 

 tiple insecticidal applications on the effectiveness of certain insecticides used to 



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