RELATION BETWEEN ELEMENTS AND NUTRIENTS 63 



Crops 



Yield 

 per aere 



Nitrogen 

 (N) 



Phosphorus 

 (P) 



Potassium 



Calcium 

 (Ca) 



Peas, green, total crop 



Potatoes, Irish (tubers). 

 Potatoes, sweet (tubers) . . 



Rye, grain 



Rye, straw 



7.5 tons 

 200 bu. 

 200 bu. 

 25 bu. 

 l}i tons 



(85) 



42.0 



35.0 



26.5 



12,0 



7.2 

 6.3 

 5.0 

 4.5 

 3.0 



35.0 

 53.0 

 51.0 

 6.6 

 16.4 



55.0 

 2.4 



" ' '6,5 

 5M 



Rye, total crop 



. 



38.5 



7.5 



23.0 



6.0 



Soybeans, grain 



Soybeans, straw 



20 bu. 

 1 ton 



70.0 

 35.0 



7.1 

 5.4 



24.6 

 32.7 



2.2 

 31.3 



Soybeans, total crop. . . . 



. . . 



(105) 



12.5 



57.3 



33.5 



Timothy hay 



2 tons 

 1500 lbs. 

 1250 lbs. 



39.0 

 41.0 

 26.0 



5.4 

 2.7 

 2.5 



45.0 

 59.0 

 33.0 



10.0 



Tobacco, leaves "^ 



Tobacco, stalk 



41.0 

 6.8 



Tobacco, total crop 







67.0 



5.2 



92.0 



47.8 



Turnips (roots only) 



Wheat, grain 



Wheat, straw 



15 tons 

 30 bu. 

 1.6 tons 



60.0 

 35.6 

 16.0 



13.0 

 6.8 

 1.8 



72.0 



7.9 



19.6 



15.0 

 07 

 4.3 



Wheat, total crop 





51.6 



8.6 



27.5 



5.0 



* Leaves and stalk containing 30 per cent moisture. 



be approximately one-fifth greater than that made by a sixty-five- 

 bushel crop. In this way we can estimate the amounts of the 

 elements removed by various yields. 



The greater the 3delds the heavier the draft upon the soil. 



The figures in parentheses in the nitrogen column indicate the 

 total nitrogen content of the legimie crops. Much of this nitrogen 

 is gathered from the air by means of bacteria in the nodules on 

 their roots. 



SOME INTERESTING AND PRACTICAL FACTS CONCERNING THE 



FEEDING OP CROPS 



Distribution of the Elements in Plants. — ^As a rule more nitro- 

 gen is contained in the grain than in the stalk or straw. Phosphorus 

 goes largely into the grain — ^the potassium and calcium into the 

 stalk, straw and leaves. Calcium is found largely in the leaves. 



Relation Between Elements and Nutrients. — Crops which 

 utilize large amounts of nitrogen are rich in protein. (Compare 

 the preceding table with the table of nutrients in the appendix.) 



