The total number of stomachs examined, exclusive of mourning doves and 

 quail, was 570. Of this number, 78 contained boll weevils. The weevils were not 

 numerous at the time when the birds were collected. As a result of this study, the 

 author urges the protection of insectivorous birds within the cotton belt. 



1906 - Howell, A. H. Birds that eat the cotton boll weevil. A report of progress. 



U. S. D. A. Bur. Biol. Survey B. 25, 22 p. 



Notes on the abundance of several species of birds occurring in cotton fields 

 and their importance as weevil destroyers, as based on numerous stomach ex- 

 aminations. 



1907 - De La Barreda, L. Las Plagas del algodonero. Comn. de Parasit. Agr. B. 4(2): 



107-215, 24 pi., 1 map. Mex. 



A presentation of the answers to a set of questions sent out by the Comision 

 regarding cotton pests, including the boll weevil. Comments upon the replies. 

 Many references made to natural enemies. 



1907 - Crawford, J. C. New hymenopterous parasites of Anthonomus grandis Boh. 

 Canadian Ent. 39:133-134. Apr. 



Original description of Torymus anthonomi , Urosigalphus anthonomi, and 

 Urosigalphus schwarzi , all reared from the boll weevil. 



1907 - Henshaw, H. W. Value of swallows as insect destroyers. U. S. D„ A. Bur. Biol. 

 Survey C. 56:4. Apr. 27. 



Attention is called to the importance of the swallow in the destruction of boll 

 weevils and other injurious insects. 



1907 - Henshaw, H. W. Birds useful in the war against the cotton boll weevil. U. S. D. A. 

 Bur. Biol. Survey C. 57:4. 



It has been found that 38 species of birds eat the cotton boll weevils to a 

 greater or lesser extent. In this connection special mention is made of orioles, 

 nighthawks, and various kinds of swallows and martins. 



1907 - Herrick, G. W. The boll weevil. Miss. Agr. Expt. Sta., C. 7 p. Sept. 

 A paragraph is devoted to the relation of birds to the boll weevil. 



1907 - Hinds, W. E. An ant enemy of the cotton boll weevil. U. S. D. A. Bur. Ent. B. 

 63(3):45-48. 



The ant Solenopsis geminata Fab., var. xyloni McC., in its relation to the 

 boll weevil. 



1907 - Hinds, W. E. Some factors in the natural control of the Mexican cotton boll 

 weevil. U. S. D. A. Bur. Ent. B. 74, 79 p. 



If there is an average amount of moisture in the soil up to the time when 

 squares begin to form, followed by a period of 4 to 6 weeks of hot dry weather, 

 the weevils may be so effectively checked as to do little injury to the cotton crop 

 of that season. 



An extreme drought, even with average temperatures, will greatly reduce 

 the number of weevils, but the crop will be small due to the lack of rain. 



Winter conditions of unusual severity, with frequent low temperatures and 

 much rainfall, reduce the number of weevils surviving hibernation and prevent 

 the survival of old cotton roots. Defoliation of cotton by the cotton leafworm may 

 be a very important factor in reducing the number of weevils in a field which may 

 enter hibernation or which are likely to survive. 



Fallen forms contain 70% of the weevil stages developing in a field. The 

 mortality occurring in fallen forms is 4 times as effective in controlling the 

 weevil as is that in hanging forms. Less than \ of all the weevil stages were 

 alive when found. All factors of natural control seem to operate more effectively 

 against weevil stages in squares than against those in bolls. 



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