Yellow Corn (6/23/11)
If zinc and sulfur were applied this spring, as many fields were treated, then the symptoms are not a true nutrient deficiency, but are the result of the leaves being in a relatively warm environment compared to the roots which are still cold from the rains and the relatively small number of days when temperatures were in the 80’s this May/June. As soon as the weather changes (next week?) and the soil warms, these symptoms will go away. Until it warms up, the corn will continue to grow slowly, the root mass will remain small relative to the tops and corn may continue to have a yellow cast to it. No amendments that I know of will take these symptoms away if zinc, sulfur and N needs have been previously addressed.
Dave Franzen - NDSU Extension Soil Specialist