indications are that the rows should be not less than 4 feet apart and the plants 

 not more than 6 inches apart in the rows to give the best assurance of suppressing 

 secondary stalks, keeping the lanes open between the rows and avoiding boll weevil 

 cotton. In case of emergency the cutting out of alternate rows might be advisable. 



1923 - McDonald, R. E. The boll weevil - A review of the methods of control. Tex. Dept. 



Agr. B. 74, 21 p., 1 map, Jan. -Feb. Austin. 



There is no known successful method of eradicating the cotton boll weevil. 

 The various practices adopted are reviewed, their efficacy depending on the region 

 of the State in which they are employed and the prevailing weather conditions. The 

 necessity for concerted community action with the adequate legislation that it re- 

 quires is pointed out. 



A map is appended showing the range of infestation in Texas in 1920-1922. 



In the introduction of this bulletin, G. G. Terrell recommends the plowing 

 under of the green cotton stalks as early in the autumn as possible. Owing to the 

 resulting lack of food, many of the weevils die before going into hibernation. This 

 method has the further advantage of improving the soil for the next crop. 



1924 - Conner, A. B., and H. J. Reinhard. Cotton boll weevil control in Texas. Tex. 



Agr. Expt. Sta. C. 32, 14 p., May. Col. Sta. 



The life history of the cotton boll weevil and the history of its effect upon 

 cotton production in Texas. The question of control, which resolves itself into one 

 of good farming, is also dealt with. Every effort should be made to destroy the 

 cotton plants in the autumn as soon as the crop is harvested and to provide the 

 best conditions for fruiting, thus ensuring profitable yields, even under boll- 

 weevil conditions. In individual cases, spraying with calcium or lead arsenate 

 may prove necessary. 



1924 - Pierce, W. D. How insects affect the cotton plant and means of combatting them. 

 U. S. D. A. Farmers' B. 890, 25 p. Dec, 1917, Rev. Jan. 



Includes discussion of the boll weevil with calcium arsenate as a control 

 measure and lists several cultural methods which would be of help in controlling 

 the boll weevil. 



1924 - Smith, G. D. Further experiments with the Florida method of boll weevil con- 

 trol. Fla. State Plant Bd. Q. B. 8(2):27-72, 9 fig. Jan. Gainesville. 



During 1923 further experiments were made with the Florida method of con- 

 trol for the cotton boll weevil, particularly with regard to weather conditions and 

 with a view to finding a method of applying the poison that would give quicker 

 mortality. 



The results of this work are summarized as follows: In most cases where 

 the Florida method was properly used, a profitable crop of cotton was secured. 

 Weather conditions during the growing season of 1923 practically prohibited suc- 

 cessful dusting of the cotton plants. A poisoned syrup mixture made by mixing 

 2 lbs. of calcium arsenate in \ U.S. gals, of water and then adding 1 U.S. gal. of 

 syrup (treacle), when mopped in the buds of the cotton plants, gave much better 

 results than dusting. Syrup is not attractive to the weevil in the sense that weevils 

 will search for it and congregate around it in numbers. Mortality records secured 

 under cage conditions, and later verified by field experiments, show that after the 

 squares are removed and the buds of the plants mopped with the poisoned syrup 

 mixture, most of the adult weevils are killed within 24 hours. 



Powdered calcium arsenate dusted on the plants by means of a dust gun re- 

 quired from 48 to 72 hours to give about the same results. Mopping the plants 

 after the squares were removed, using the poisoned syrup mixture, was found to 

 be cheaper than making one application of calcium arsenate dust, using a rotary 

 fan type of dust gun at the rate of 5 lbs. per acre. The Florida method of weevil 

 control can be effectively used under adverse weather conditions if the poison is 

 applied in the form of the poisoned syrup mixture. 



The cost of removing the squares varied from about $0.54 to $1.90 per acre, 

 depending on the space of the plants in the row and the number of squares on the 



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