How do soils become potassium deficient?
The most common cause is potassium applications that fall well below what is removed from the field at crop harvest. Soybeans can remove substantial amounts of potassium, more than corn in many areas. But forage crops, like corn silage and alfalfa, by far remove the most. The reason is that much of the potassium in the plant is found in vegetative parts, like stems and leaves. When these are removed from the field, substantial amounts of potassium are also removed. Failing to account for these losses and under-fertilizing with potassium can lead to problems. What problems does potassium deficiency cause? Soils that are very low in potassium reduce yields and quality. A real problem for many is the effect low potassium has on nitrogen efficiency. If only nitrogen is applied on potassium deficient soils, overall yields can be reduced far below where the same amount of nitrogen is applied on soils with adequate potassium. This reduces the amount of grain or forage produced per pound of ni
