CHAPTER VII 

 INSECTS AFFECTING SWEET POTATOES 



It is commonly thought that the sweet potato is not 

 affected seriously by insect pests. The home garden or 

 small patch many seasons is practically free from in- 

 sect injury, but the commercial grower will have to fight 

 several insect enemies, some of which do millions of 

 dollars' worth of damage annually to the sweet potato 

 crop. The different sections of the country have their 

 specific insect enemies, the southern states possessing 

 by far the greater number and suffering much more 

 material damage than the eastern and middle western 

 states. 



Insects that affect the sweet potato plant are divided 

 into two general classes, the biting or chewing insects, 

 and the sucking insects. The first class destroy parts 

 of the plant or the tubers by gnawing or eating, and 

 leave visible signs. The sucking insects obtain their 

 substance by sticking a small thread-like bill into the 

 plant and drawing the juices out without leaving visible 

 signs to the natural eye. The first class, or biting in- 

 sects, usually do much more damage than the sucking 

 insects. 



THE SWEET POTATO FLEA-BEETLE 



(Chcetocnema confmis) 



As soon as the sweet potato plants are set in the field, 

 they are often attacked by millions of small brownish- 



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