Potassium (K) deficiency symptoms are beginning to be observed on many corn fields and in some soybean fields. The symptom for both crops is yellowing of the leaf margins of the older leaves that usually begins at the leaf tip and extends down the margins toward the leaf base. With severe deficiency the leaf edges may become brown (the tissue dies) and affected plants will appear stunted, although the newest leaves may be normal. For further information of symptoms, see ICM 7/1/2002 (Corn leaf potassium deficiency symptoms) and ICM 7/1/2002 (Is it iron or potassium deficiency?)