150 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



farther south before they had become abundant in Kansas fields 

 so as to hasten their control of the aphides, but further experi- 

 ments will be necessary before it can be determined whether such 

 a method of colonizing the parasites is practically effective or not. 

 Control. Most important of all methods of control is the aban- 

 donment of the growing of volunteer oats and the destruction of 

 all volunteer oats and wheat i;i the early fall. Universal experi- 



FIG. 116. Parasitized green bugs enlarged. 



S. J. Hunter.) 



(From photograph, after 



ence throughout the injured area shows that relatively little injury 

 occurs where volunteer oats are not grown. 



Where small spots of grain have been injured by the pest in late 

 winter, which is the way an outbreak usually begins in southern 

 localities, the aphides on these small spots may be killed by spray- 

 ing with 10 per cent kerosene emulsion, or whale-oil soap, 5 pounds 

 to a barrel of water, by covering the spots with straw and burning, 

 or by plowing under the infested spots. Were this generally done 

 before the aphides commence to multiply rapidly, it is entirely 

 possible that widespread injury might be averted. 



