6 FIELD AND LABORATORY STUDIES OF CROPS 



same way that sugar and salt are dissolved. In this condi- 

 tion plant food can be taken in by the roots as easily as pure 



Fig. 3. — The Roots of the Corn Plant Absorb Food Materials from the 

 the Soil to the Depth of Three Feet or More. 



water. We think of the " clear-as-crystal " well-water that 

 we drink as being pure water, but we know that often it 



