Further Experiments on the Economic Value of Root Crops 



553 



TABLE 3. Analyses of Corn and of Mangels for Four Years 



(Percentages) 



Comparative acre production of nutrients 



The above table shows that both the corn and the mangels used in these 

 experiments were richer in nutrients than are those commonly grown for 

 such purposes. The superiority of the mangels is due partly to the selec- 

 tion of varieties. The high food value of the corn is due partly to its 

 degree of maturity and partly to the acclimated variety used. A truer 

 index of the production of nutrients by corn and by mangels is found by 

 calculating the weight of the total nutrients, and of each kind separately, 

 produced on an acre of land. The results are shown in the following table : 



TABLE 4. Acre Production of Nutrients from Corn and Mangels 



for Four Years 

 (Pounds) 



25 



