results as calcium arsenate alone at 7 lbs. per acre. The results were not un- 

 satisfactory when the proportion of hydrated lime was doubled and the rate was 

 increased to 9 lbs. per acre. This mixture would be cheaper and would lessen the 

 danger of arsenical injury to the soil and of infestations by aphids that often fol- 

 low heavy applications of calcium arsenate. 



1934 - Young, M. T. Field-plot tests for boll weevil control at Tallulah, Louisiana, 



during 1933. J. Econ. Ent. 27(4):749-756. 



In 1933, 8 cotton fields were divided into comparable plots, of which one was 

 untreated and the others dusted with various insecticides for the control of the 

 boll weevil. All applications were begun as soon as 10% of the squares had be- 

 come infested. They were repeated (between daybreak and 7:30 a.m.) at 4-day 

 intervals, so far as weather conditions permitted. If heavy rain occurred within 

 24 hours of an application, the dust was considered ineffective and another appli- 

 cation was made. Weekly records of the percentage of squares infested were 

 begun as soon as the plants had 4 or 5 squares large enough to be punctured by 

 the boll weevil and were continued until the average number of squares to a plant 

 was less than 4 or 5. Yield records were based on pickings from selected areas 

 from those parts of the plots least liable to be affected by the adjacent ones. 



The following figures show the estimated yield of seed cotton in lbs. per 

 acre from one field following 7 effective applications of various dusts: untreated, 

 792; calcium arsenate (at an average rate of 5.3 lbs. per acre in each application), 

 1,077; sodium fluosilicate (8-12 or 4-6 lbs. per acre), 727 and 657 respec- 

 tively, with some scorching of foliage; cryolite (sodium fluoaluminate) (6 lb.), 

 781; barium fluosilicate (5.4 lb.), 823. In another field, calcium arsenate and 

 Paris green (3:1), especially when wet-mixed, gave better results in some tests 

 than calcium arsenate, alone, but tended to scorch the foliage. Calcium arsenate 

 and copper arsenate (3:1 or 4:1) appeared to give very good control of A. grandis, 

 but the yields were not so great as on the plot treated with calcium arsenate alone. 

 The results of applying calcium arsenate with a combined cultivator and duster 

 were variable and inferior to those of dusting with hand guns; this mode of appli- 

 cation is nevertheless considered to offer some promise. 



1935 - Anonymous. Ala. Agr. Expt. Sta. Rpt. 45:26-28. 



E. L. Mayton and J. M. Robinson give further details of the effect of dusting 

 with calcium arsenate, for the control of the boll weevil, on plots of cotton used 

 for experiments, with different rates of application of a chemical manure. In 7 of 

 the 13 years for which the manuring experiment was carried out, the infestation 

 necessitated dusting. This resulted in an average increase of 352 and 55 lbs. of 

 seed cotton per acre on the fertilized and unfertilized plots, respectively. 



1935 - Gaines, R. C. Ann. meeting of the Cotton States Branch and of the Texas Entomo- 

 logical Society. J. Econ. Ent. 28(1) :54. 



Reports the development and emergence of boll weevils from buds of althea 

 (Hybiscus syriacus ). So far as is known, this is the first time that the boll weevil 

 has been found breeding in a plant other than cotton and Thurberia (Arizona wild 

 cotton) growing under field conditions. In field-plot tests for boll weevil control 

 at Tallulah, La., M. T. Young of the U.S. Bureau of Entomology, obtained an 

 average increase of 419 lbs. of seed cotton per acre over the untreated check 

 plots from the use of calcium arsenate by the standard method. The gains ranged 

 from 187 lbs. to 617 lbs. of seed cotton per acre, or from 28.6% to 72% over the 

 respective check plots. 



1935 - Strong, L. A. Report of the Chief of the Bureau of Entomology and Plant Quaran- 

 tine. U. S. D. A. Wash. 



Tests for the control of the boll weevil with dusts of thiodiphenylamine and 

 sulphur, and with derris in inert carriers, gave promising results. Early morn- 

 ing applications of calcium arsenate were more efficient than those made at mid- 

 day or in the evening. Equal parts of calcium arsenate and hydrated lime applied 

 at the rate of 7 lbs. per acre gave as good control as calcium arsenate alone at 

 the same rate. 



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