THE BOLL- WEEVIL PROBLEM, 17 



METHODS OF CONTROL. 



It will be evident from the preceding statements regarding the life 

 history and habits of the weevil that its control is beset with many 

 difficulties. Its insidious methods of work in the immature stages 

 -^itliin the fruit of the cotton plant, the habit of the adult in seeking 

 protection for the greater part of the time under the bracts of the 

 squares, and its enormous power of reproduction and adaptabiHty to 

 new conditions, all tend to place the boll weevil in a class by itself. 

 The difficulties are increased by the necessary procedures in raising 

 cotton. In spite of these difficulties, fairly satisfactory means of 

 control are known. A large share of the reasonable success of the 

 warfare against the pest is due to the assistance furnished by natural 

 agencies, which commonly destroy many more weevils in a cotton 

 field than the farmer could by any known method or methods. 



The writer wishes to emphasize the following important points that 

 have a direct hearing upon control: 



(1 ) The weevil has no food plant hut cotton. 



(2) The mortality of the weevil during the winter is very high. 



(3) The emergence from hihernating quarters during the spring is 

 slow and prolonged until well into the summer. 



(4) Early in the season, on account of comparatively low tempera- 

 tures, the development of the weevil is much slower than during the 

 summer months. 



(5) The dnjing of the infested squares soon destroys the immature 

 stages of the weevil contained therein. 



(6) The weevil is attacTced hy many different species of insect enemies. 



(7) The weevil has little ability to emerge when huried under wet soil. 



DESTROYING INFESTED PLANTS IN THE FALL. 



The process of destroying the infested plants in the fall has been 

 recommended by the Bureau of Entomology and other agencies for 

 many years. It is a step of the greatest general importance, though 

 it can not be applied alike to aU regions. It is of the greatest impor- 

 tance in southern localities, where the boll-weevil problem is most 

 serious. In the northern portions of the infested territory it is less 

 important on account of the effect of climatic conditions on the 

 weevil. Its practicability depends upon the supply of labor avail- 

 able and upon the size of the plantings. On the very large planta- 

 tions in the Mississippi Valley this difficulty is especially marked, 

 but even in that region fall destruction can often be practiced to good 

 advantage. It frequently happens that smaU portions of the field 

 remain green and attract enormous numbers of weevils after the tune 

 when very few are to be found scattered generally in the fields. 

 These areas are generally of such a small size that it is entirely 

 102523°— Bull. 848—17—3 



