CHAPTER XXIII 

 COTTON — INSECT ENEMIES 



The most destructive insects attacking the flowers or 

 bolls are the boll-worm and the Mexican cotton boU- 

 weevil. 



Among the insects most injurious to the foliage are the 

 cotton caterpillar. The cotton red-spider also injures 

 the leaves, and on the young seedlings a plant-louse is 

 sometimes troublesome. 



The roots are invaded by a very small animal called 

 the nematode worm. The stems of the young plants are 

 attacked by cutworms and the buds by cowpea-pod weevils. 



The Cotton Boll-worm. — Heliothis obsoleta 



359. Life history of boll-worm. — The boll-worm is 

 one of the most widely distributed enemies of cotton. 

 The only parts of the cotton plant injured are the squares 

 or bolls, which are eaten into and the interior destroyed 

 by the caterpillar stage of a moth. Other plants that 

 are much injured by the same worm are corn and to- 

 matoes. (See corn ear-worm, paragraph 192.) 



The parent is a moth (Fig. 167) which may lay more 

 than one thousand eggs. These are laid by preference on 

 the fresh silks of corn, so that the young worm, as soon as 

 hatched, may enter the tip of the ear, where it is commonly 



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