UNITED STATES DEPARTMENT OF AGRICULTURE 



SW'&J-u 



BULLETIN No. 564 



Contribution from Bureau of Entomology 

 L. O. HOWARD, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



October 4, 1917 



COLLECTION OF WEEVILS AND INFESTED SQUARES AS A 

 MEANS OF CONTROL OF THE COTTON-BOLL WEEVIL IN 

 THE MISSISSIPPI DELTA. 



By B. R. Coad and T. F. McGehee, Entomological Assistants, Southern Field Crop 



Insect Investigations. 



CONTENTS. 



General statement of experiments conducted . 1 



Brief review of 1915 experiments 2 



Lines of investigation in 1916 3 



Time interval between bag-and-hoop collec- 

 tions in relation to proportion of infested 



forms secured 3 



Plat tests of the value of the bag-and-hoop as 

 a means of weevil control under field con- 

 ditions 18 



Experiment on Hecla Plantation 18 



Eureka Plantation experiment number 1 27 



Page. 

 Studies on the value of a mechanical collector 



of boll weevils 37 



Flattest 38 



Comparative efficiency studies 41 



General considerations and summary 42 



GENERAL STATEMENT OF EXPERIMENTS CONDUCTED. 



During the cotton-growing seasons of 1915 and 1916 the writers 

 conducted a series of studies to ascertain the value of various meth- 

 ods of collecting boll weevils and infested cotton forms as a means 

 of control for the cotton-boll weevil. The experimental work was 

 conducted in the vicinity of Tallulah, La., while more or less ex- 

 tensive observations were made at various points throughout Lou- 

 isiana and Mississippi. The following studies apply most directly 

 to the conditions existing in what is termed the " Delta" of Louisiana 

 and Mississippi, but are also undoubtedly applicable to other por- 

 tions of the cotton belt where a severe weevil infestation prevails. 



In July, 1916, the senior writer published a preliminary report on 

 the results of the 1915 studies * in order to place the information 

 secured in a form available for use by the planters. 



Note. — This bulletin will be of interest to entomologists and to cotton growers in the Delta region of 

 Louisiana. 



1 Coad, B. Pv. Cotton-boll Weevil Control in the Mississippi Delta, with Special Reference to Square 

 Picking and Weevil Picking. U. S. Dept. Agr. Bui. 382, July 8, 1916. 

 96828°— Bull. 564—17 1 



