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36 THE SPRING GRAIN-APHIS OR GREEN BUG. 



before they were ready to head out the aphidids disappeared. This 

 was probably due to the presence of the parasites. Wheat was not 

 attacked or injured by these aphides. Mr. Parks did not have any 

 of this material identified, and we can not say absolutely that this 

 was Toxoptera graminum Rond., but the character of the attack, the 

 sudden disappearance of the aphidids, and the fact that they did not 

 disturb wheat coincide with our observations on this insect in this 

 latitude and to us clearly point to Toxoptera as the originator of the 

 trouble. 



Part of the trouble referred to in letters cited in Bulletin 210 of the 

 Ohio Agricultural Experiment Station was, in all probability, due to 

 "green-bug" attack, since from our own observations on this species 

 in northern latitudes a part of this injury appears to be characteristic 

 of Toxoptera. 



North and South Carolina also suffered somewhat from the depre- 

 dations of this insect in 1907. The senior author made a trip into 

 this section, reaching Sumter, S. C, April 17, 1907. He found that 

 all fields of oats, the only grain sown, were more or less affected; here 

 and there brown areas occurred, showing the characteristic work of 

 Toxoptera. This condition was noticeable from Sumter, S. C., to 

 Charlotte, N. C, indicating that the infestation was general. Both 

 MacrosipJium granaria Buckt. and Toxoptera graminum Pond, were 

 present, but the latter was by far the more numerous. There were 

 very few parasites or coccinellids in evidence. In a letter dated June 

 18 Mr. E. C. Haynsworth, of Sumter, stated that soon after the 

 senior author's visit in April the weather became warmer and Toxop- 

 tera disappeared very rapidly. 



In some parts of North Carolina the injury was quite serious. Mr. 

 Franklin Sherman, jr., of the North Carolina Department of Agricul- 

 ture, has kindly placed his notes on this outbreak at our disposal. 

 He stated that the worst area of infestation centered about Winston- 

 Salem, in Forsyth County, N. C, although some injury was also 

 inflicted in Guilford, Davie, and Rowan counties in the same State, 

 some fields being almost totally destroyed. Parasites were present, 

 though not in sufficient numbers to hold Toxoptera in check. 



The senior author went directly from Sumter, S. C, to Winston- 

 Salem, N. C, reaching the latter place April 19, where he was met by 

 Mr. Sherman, and they went over the ground together. A number 

 of fields were examined, ranging from slightly infested to totally 

 destroyed. In some fields of wheat, where there had been quantities 

 of volunteer oats, the infestation was more severe. Parasites were 

 present in great abundance in some fields, but they did not appear to 

 have checked the pest in time to save all of the fields. 



The senior author thus summarizes this outbreak: 



From a study of the entire neighborhood it seems quite evident that the outbreak 

 of Toxoptera in the vicinity of Winston-Salem was primarily due to the presence of 



