1918 - Howard, L. O. Report of the entomologist. U. S. D. A. Bur. Ent. Rpt. 24 p. 



Sept. 19. Wash. 



"Work against southern field-crop insects carried out under Dr. W. D. 

 Hunter have resulted in the discovery that the cotton boll weevil . . . can be 

 controlled by dusting with lead arsenate or calcium arsenate." 



1919 - Ballou, H. A. The poisoning of the boll weevil. Agr. News, 18(443): 122- 123. 



Apr. 19. Barbados. 



Success of experiments in the United States to control the Mexican cotton 

 boll weevil on a large scale by means of poisons; methods of application and 

 machinery used. 



The poison used was a calcium arsenate containing not less than 40% arsenic 

 pentoxide and not more than 0.75% of water-soluble arsenic and of a density of 

 not less than 80 cubic inches per lb. The poison was applied as a dust, 6 lbs. 

 being required per acre for each application. The fields were sprayed from 2 to 



4 times during the season; in the event of heavy rain within 24 hours, the dusting 

 was repeated. The best time for application was when the leaves were damp and 

 the air calm. The power duster was able to cover at least 6 acres an hour; 

 whereas the capacity of each hand dust gun is about 5 acres per day. 



1919 - Hinds, W. E. Cotton worm control. Ala. Agr. Expt. Sta. C. 42:63-67, 2 pi. Aug. 

 Auburn. 



"The boll weevil may be controlled with calcium arsenate applied by means 

 of a dust gun so as to drive the poison well through the plants. This treatment 

 should be applied weekly and maintained as long as the cotton continues to grow 

 and set bolls." 



1919 - Hinds, W. E. Report of entomologist. Ala. Agr. Expt. Sta. Rpt. 31:27-29. 

 Jan. Auburn. 



"Experiments with lead arsenate and other poisons in dust forms against 

 the boll weevil . . . on cotton are being continued." 



1919 - Hinds, W. E. Annual report of the director of the experiment station on work 

 done under the Local Experiment Law in 1919. Ala. Agr. Expt. Sta. C. 43. 

 Auburn. 



A report of cotton dusting with calcium arsenate on three farms in Ala- 

 bama. One farm showed a profit of $20 per acre from dusting; one, $22 per acre; 

 and the third showed doubtful profit. Although farmers are interested in dusting, 

 very few are willing to take steps to provide machinery and poison necessary 

 until its value is completely proven. 



1919 - Hinds, W. E., and F. L. Thomas. Poisoning the boll weevil. Ala. Agr. Expt. 

 Sta. B. 212:53-84, 1 pi., 16 tab. Nov. Auburn. 



Dusting experiments with calcium arsenate against the boll weevil carried 

 out in Alabama from 1918 to 1920. In 1918 the rate of application varied from 1 to 



5 lbs. per acre at intervals of about 14 days, but the slight increase in yield did 

 not warrant the expense of dusting. This failure was partly due to weather con- 

 ditions, the heat and drought controlling most of the weevils. Also, the intervals 

 between applications were too great and the work was not continued long enough 

 for the results to become cumulative under existing conditions. Experiments 

 showed that the weevils will live without water for a short period, at least, and 

 that dew is not indispensable in poisoning them. Moisture on the plants after the 

 poison had been applied did not increase the mortality. In 1919, experiments on 

 the cost of dusting with calcium arsenate showed that it was advisable to keep the 

 acreage of cotton moderate and to make that area as fertile as possible so as to 

 increase its productiveness. Under these conditions, should a heavy weevil infes- 

 tation be indicated, the pest may be reduced to below 30% by dusting every 5th 

 day until after a full crop of bolls is beyond weevil damage. 



In all counties where the weevil caused an average decrease in yield of more 

 than 20% during 5 consecutive years, dusting is likely to be needed regularly each 

 year. 



