34 DEPARTMENT BTJLLETIN 779. 



6. Wheat, barley, and rye are the preferred food plants among the 

 cultivated crops. The species also feeds upon other cereals, and upon 

 alfalfa, cotton, peas, beans, cabbage, tomato, and lettuce, in addition 

 to many native plants. 



7. The first recorded damage occurred in 1903, and since that time 

 destructive outbreaks have been reported from most of the States 

 west of the Great Plains area. 



8. Weather influences and the "work of parasites generallv restrict 

 destructive outbreaks in each locality to periodic intervals of two or 

 three years. 



9. Adults emerge from hibernation in the early spring and deposit 

 eggs on the material composing the hibernating quarters. The re- 

 sulting nymphs feed upon tender plants growing in the vicinity. 



10. Upon reaching maturity the adults migrate to grain fields and 

 feed upon the developing heads. . 



11. There are three distinct generations and sometimes a partial 

 fourth generation annually. About 50 days are required to complete 

 the life cycle of each generation. 



12. After midsummer the numbers of the inseets are greatly re- 

 duced by an egg -parasite,' Telenomus asJimeadi, and by two species 

 of tachinid parasites, GyrrunosoTna fuliginosa and Oeypterodes 

 euchenor, which parasitize the adults. Several kinds of predacious 

 enemies contribute to the same result. 



13. Hibernation occurs in the adult stage under weeds or rubbish. 

 No nymphs or eggs survive the winter. 



14. Severe winters result in the death of a large percentage of 

 hibernating adults and constitute one of the most important factors 

 in restricting destructive outbreaks of the species. During normal 

 winters at least 95 per cent of the adults survive when hibernating 

 in protected locations. 



15. The most effective and practical method of control is the de- 

 struction of the adults while they are concentrated in their winter 

 quarters. This is best accomplished by plowing under, or burning, 

 all rubbish and weeds, particularly Eussian thistle, in and about cul- 

 tivated fields. These control measures should be included as a part 

 of the regular farm practice and any special work required may be 

 carried on during the inactive season at a time when the farm labor 

 and equipment ordinarily are idle. 



16. Trap crops, hand picking, and hopperdozers might prove 

 practical in the control of the insect under special conditions. 



LITERATURE CITED. 



(1) Stal, C. 



1872. Enumeratio Hemipteroruin . . . Part 2. 159 p. Stockholm. In 

 Kongl. Svenska. Vetenskaps. Akad. Handlingar, v. 10. no. 4. 



Page 33 : Described as Lioderma subg. ChlQroQhroa. Original descrip- 

 tion in Latin. 



