PAPERS ON BIOLOGY AND AGRICULTURE 151 



the surface soil on the plots plowed with the deep tillage 

 machine was distinctly changed, showing a mixing of the 

 subsurface and subsoil with the surface, but that no such 

 inversion has taken place on the subsoiled or djTiamited 

 plots, and that no effect on the drainage could be discerned 

 on any of the plots. 



