FIELD EXPERIMENTS IN THE SOUTH 



485 



TABLE 97. CROP YIELDS IN ILLINOIS SOIL EXPERIMENTS: VIENNA FIELD 

 Corn, Bushels per Acre 



Oats or Wheat, Bushels per Atre 



average of the type, although large areas are to be found as badly 

 worn as the field from which this soil was collected. This field has 

 been under cultivation for about seventy-five years, and was still 

 cropped when the soil was collected. During the earlier period of 

 its cultivation the soil frequently produced 25 bushels of wheat an 

 acre, but during the later years about 5 bushels has been the aver- 

 age crop in normal seasons. 



Table 98 gives the results of seven years' experiments with pot 

 cultures on this type of soil. It is seen that practically no gain has 

 been made except where nitrogen was supplied, either directly in 

 commercial form or indirectly by means of legume treatment. It 

 should be borne in mind that no legume treatment preceded the 

 1902 wheat crop. The catch crop of cowpeas, which was planted 



