INSECTS INFESTING THE SWEET POTATO 24I 



tion. The first application is to accomplish the destruction of 

 the beetles before they deposit their eggs, and the second and 

 third are to kill beetles that may come from other plants. Rota- 

 tion of crops and the avoidance of planting in the vicinity of 

 neglected ground that has grown up with bindweed and wild 

 morning-glory are also advisable. 



The Common Sweet-potato Sawfly (Schi::occi'us cbenus Nort.). 

 — The larvx of two species of sawflies have been observed doing 

 injury to sweet potato. 

 They are comparatively 

 new as pests and of similar 

 habits and distribution from 

 New York to the Gulf and 

 northward to Nebraska. 



The present is like other 

 sawflies, four-winged, and 

 somewhat smaller than a 

 house fly, the body is black, 

 and the wings infuscated 



_ 1 1 r^, , , Fig. \Z7 .—Eubadizon schiaoceri. Parasite of 



or dusky. The male has %^eet-potato sawfly. (After insect Life) 



. forked antennae while the 



female has shorter simple ones. Eggs are deposited in the leaf of 

 sweet potato. Attack has been observed in August and Sep- 

 tember in Mississippi, and a parasite (fig. 157) has been reared 

 from the larva. This parasite, and a tachina fly, which also 

 preys on it, no doubt hold the insect in check and prevent 

 serious injury. 



The Larger Sweet-potato Sawfly {Schizoccrus privatus 

 Nort.). — The first record that we have of injury by the larvae 

 of this sawfly was in July, 1890, when it damaged sweet potato 

 in Virginia. At that time plants that were attacked produced 

 no yield whatever. This sawfly is larger than the preceding, 

 the wing expanse being nearly 3/5 of an inch, and both sexes 

 have yellow abdomens. Other differences can be made out by 



