CONTROL of the corn root-aphis, which can be ac- 

 complished by the simple practices described in 

 this bulletin, is important because, in addition to corn, 

 cotton, and asters, this insect feeds on the roots of cer- 

 tain weeds and everywhere is fostered by a common 

 species of field ant. 



The control measures are — 



Crop rotation. 



Early and deep spring plowing followed by several 

 deep diskings to demoralize the aphid and ant col- 

 onies and to prevent the growth of weeds on which 

 the aphis lives previous to the appearance of corn. 



The use of a substance possessing a pungent odor, 

 applied with a chemical fertilizer and distributed by 

 means of a fertilizer attachment to the corn planter, 

 to repel the ants and prevent them from placing 

 aphids on the roots of the corn or other cultivated 

 crop. 



The use of barnyard manure or other fertilizer as 

 an aid in producing stronger plants. Though this does 

 not reduce the number of aphids, directly or indi- 

 rectly, it enables the plants lo withstand injury better. 

 It is recommended only as supplemental^ to the prac- 

 tices already mentioned. 



