161 



The facts that in all stages except the imago the weevil lives within- 

 the fruit of the plant, well protected from any poisons that might her 

 applied, and in that stage takes food normally only by inserting its 

 snout within the substance of the plant; that it is remarkably free- 

 from parasites or diseases; that it frequently requires but 14 days for 

 development from egg to adult, and the progeny of a single pair in a 

 season may exceed 12,000,000 individuals; that it adapts itself to- 

 climatic conditions to the extent that the egg stage alone in Novem- 

 ber may occupy as much time as all the immature stages together in- 

 Jul}" or August, are factors that combine to make it one of the most 

 difficult insects to control. It is, consequently, natural that all the 

 investigations of the Bureau of Entomology have pointed toward 

 the prime importance of cultural methods of controlling the pest. 

 All other methods must involve some direct financial outlay for 

 material or machiner}^, and are consequently not in accord with 

 labor conditions involved in cotton production in the United States.. 

 Moreover, the cultural methods are in keeping with the general tend- 

 ency of cotton culture; that is, to procure an early crop, and at the- 

 same time have the great advantage of avoiding damage by a larger 

 number of other destructive insects, especially the bollworm.^ Never- 

 theless, it must not be understood that attention has not been paid 

 to the investigation of means looking toward the extermination of 

 the pest. As a matter of fact, every suggestion, from the possibilitjr 

 of breeding resistant varieties to the use of electricity in destro3dng^ 

 the weevil, has been fully investigated. The results have all beert 

 negative. 



CULTURAL METHOD. 



As has been pointed out by Dr. L. O. Howard, successful methods^ 

 of combating injurious insects may be classified into three categories r 

 (1) The propagation of parasites; (2) expedients in managing the crop 

 that have a tendency toward mitigating damage; (3) direct means^ 

 such as spra3^s. Of course the first method is, in many respects, the- 

 most elffective, although it can not be expected to be applied to a great 

 number of pests. The second method is undoubtedly more effective- 

 than the third, because it does not involve the use of special machiner3r 

 or any materials that are not in use upon every farm. In the cultural 

 method of avoiding damage by the boll weevil, it is considered that 

 a fairly effective remedy has been discovered. In some respects the 

 term cultural method is misleading. It is frequently used simply in 

 the sense of careful and persistent cultivation of the crop. However,, 

 the term includes the various modifications of the cropping system 



«See Farmers' Bui. No. 212 and Bureau of Entomology Bull. No. 50, the Boll- 

 worm, 



16780— No. 5 1— 05 1 1 



