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 ME 



c o 



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 



