» . .,_,__„ ^^ -. « ' 



40 THE SPRING GRAIN-APHIS OE k ' GREEN BUG. 



If we average the 5-year period and calculate the loss on this basis 

 for 1907. it will be seen that the total crop for Kansas. Oklahoma, 

 and Texas fell about 50.000.000 bushels short of this average — both 

 wheat and oats being considered. Seventy per cent of the Texas 

 wheat acreage was abandoned. 



This does not represent the loss as it actually occurred in various 

 parts of the States, as some parts of each State were more badly 

 affected than others and the good parts would bring up the yield for 

 the poorer portions. Sumner County. Kans.. is a good illustration 

 of this. It is located in the extreme southern portion of the State 

 and was in the badly infested districts. To quote from a letter from 

 Mr. George H. Hunter, of Wellington. Kans.. dated February 6. 1908: 



I wish, to explain that our crop of winter wheat in Sumner County for the year 1907 

 amounted to 1.909.574 bushels; this is our latest estimate, while the general average 

 is about four and one-half million bushels for Sumner County, and that would be a 

 safe basis :': r yon to figure on. According to our acreage last year, if it had not been 

 for the green bugs. I think we would have had at least four to four and one-half million 

 bushels of wheat. 



THE SITUATION IX 1911. 



The winter and spring of 1910-11 west of the Mississippi River, 

 but not east of it. was such as would tend to bring about another 

 invasion from the pest. Some injury was reported, accompanied by 

 specimens, from Pecos River valley in southeastern Xew Mexico. 

 Mr. J. T. Monell of this bureau, however, visited the locality in 

 April and reported the pest as having disappeared without doing 

 serious injury. The material received was almost universally para- 

 sitized by A\ 8 tegtaceipes Cress., which probably overcame the 

 Toxoptera before its occurrence reached the magnitude of an invasion. 



There was also a limited incipient outbreak in eastern Oklahoma, 

 which was investigated by Mr. Kelly. Here. too. the parasites 

 apparently gained supremacy before serious injury was done, except 

 perhaps in a few isolated cases. 



There is little doubt that the unusual and excessively high tempera- 

 ture for even a mild winter that prevailed throughout the Southwest 

 during a portion of the winter months was sufficient to revive the 

 parasites as well as to aid their host, and thus bring about conditions 

 that enabled the parasites to prevent the aphidids from increasing in 

 numbers to a point where thev were bevond their control. 



