538 THE SMALL GRAINS 



yields of grain in the Plains states, giving the name of 

 " soil sickness " to the conditions of the land thus brought 

 about. Just one thing, crop rotation, will be the chief 

 means of overcoming these conditions, but there should 

 be added, seed-treatment, seed selection, drainage (where 

 needed), and the use of an intertilled crop. 



