No. 5/April 25, 1997
Micronutrient Needs in Illinois
We have received reports of someone recommending boron, copper, and zinc for corn and soybeans. Research has shown that the potential for zinc deficiency is low in Illinois, and that the potential for copper and/or boron deficiency is even less. Because there is a possibility that applying boron could cause seedling damage and there is no evidence of response, use extreme caution in following any boron recommendation for corn and soybeans. Boron is needed on alfalfa. Be sure to watch for deficiency symptoms, and apply if the need develops.
As with any nutrient, make sure that you know that you have the problem before using the product. Remember that soil tests for the micronutrients are not very reliable predictors of deficiency. If your test shows a high reading, you can be confident that you do not have a problem; but, if the test is medium to low, you may or may not have a problem.
Robert Hoeft, Department of Crop Sciences, (217)333-4424