SOILS 105 



Produce 



Kind and amount Nitrogen Phosphorus Potassium 



Corn, grain (100 bu.) 100 17 19 



Corn, stover (3 T.) 48 6 52 



Oats, grain (100 bu.) 66 11 16 



Oats, straw (2i/2 T.) 31 5 52 



Wheat, grain (50 bu.) 71 12 13 



Wheat, straw (2% T.) 2j> 4 45 



Timothy hay (3 T.) 72 9 71 



Clover, seed (4 bu.) 723 



Clover, hay (4 T.) 160 20 120 



Alfalfa (8 T.) 400 36 192 



Apples (600 Ibs.) 47 5 57 



Potatoes (300 bu.) 63 13 90 



Fat cattle (1,000 Ibs.) 25 7 1 



Fat hogs (1,000 Ibs.) 18 3 1 



Milk (10,000 Ibs.) . . 57 7 12 



Butter (500 Ibs.) 1 .2 .1 



The value of the elements may be computed on the basis 

 of a common market price for available plant-food, as fol- 

 lows: 



Nitrogen .15 cents per Ib. 



Phosphorus 12 " " " 



Potassium 6 " " " 



The plant-food required for one acre of wheat yielding 50 

 bushels, one acre each of corn and oats yielding 100 bushels, 

 and one acre of clover yielding 4 tons, is the total crop 

 need of: 



Potassium 320 pounds 



Magnesium 68 " 



Calcium 168 



Phosphorus 77 " 



From these figures one may estimate the cost of fertilizers 

 in maximum crop production. 



