126 ECONOMIC IMPORTANCE OF GREEN PLANTS 



fiber, cottonseed oil, a substitute for olive oil, is made from the 

 seeds, and the refuse remaining makes an excellent cattle fodder. 

 Cotton Boll Weevil. The cotton crop of the United States has 

 rather recently been threatened with destruction by a beetle called 

 the cotton boll weevil. This insect, which bores into the young 



GULF OF 



Map showing the spread of the cotton boll weevil. It was introduced from Mexico 

 about 1894. What proportion of the cotton raising belt was infected in 1908 ? 



pod of the cotton, develops there, stunting the growth of the fruit 

 to such an extent that seeds are not produced. The loss in Texas 

 alone is estimated at over $10,000,000 a year. The boll weevil, 

 because of the protection offered by the cotton boll, is very diffi- 

 cult to exterminate. The weevils are destroyed by birds, the 

 infected bolls and stalks are burnt, millions are killed each winter 



