Abstract The addition of CaCO3 and MgCO3 to Yolo loam soil (pH 6) resulted in lower Fe concentrations in shoots of the Fe‐inefficient Ys1/Ys1 corn inbred (Zea mays L.) and higher levels in shoots of the Fe‐efficient WF9 inbred than in controls. When 59Fe with and without carrier FeSO4 was blended with the soil, the specific activity was similar for the two inbreds in nonamended soils, but was increased in the Ys1/Ys1 for the lime amendments. Sulfur acidification of soil decreased the specific activity of 59 Fe in shoots by increasing the pool of available Fe. From 5 to 33% of the Fe in plants came from the FeSO4 source. It was greatest in Ys1/Ys1 with lime‐amended soils and least in S‐acidified soil.