10,000 lbs of Nitrogen
An average Iowa soil contains about 10,000 lbs of nitrogen/acre in organic matter. This nitrogen isn’t susceptible to rapid loss. Farmers apply about 150 lbs/acre of nitrogen to corn fields to increase growth. Farmers do not apply nitrogen to soybean fields. Corn removes about 100 lbs/acre during harvest when the yield is about 175 bushels/acre. Soybeans remove about 175 lbs/acre during harvest when the yield is about 55 bushels/acre.