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IOWA ACADEMY OP SCIENCE 
oak, and Q, macrocarpa, the bur oak, while on the loess of the Kansan Q. alM, 
the white oak, and Q. rubra, the red oak, take possession. This change is strik- 
ing even in places where surface overwash, etc., have made the immediate 
surface deceptive. 
The foregoing considerations suggest something of the importance of the 
study of plants in the field in connection with loess investigations and justify 
the title of this paper. 
