Recent studies have shown that the nitrogen (N) status of a corn crop can be assessed by measuring nitrate concentrations in the lower portion of cornstalks at the end of the growing season. This finding led to the development of a new tissue test that can be used to evaluate N management practices used in any field in any year. The test is called the "end-of-season cornstalk test." An ISU Extension pamphlet, Cornstalk Testing to Evaluate Nitrogen Management [1], Pm-1584, describes the test and how it should be used.

To obtain a copy of the free fact sheet, contact your county extension office or the Extension Distribution Center [2], 119 Printing and Publications, Iowa State University, Ames, Iowa 50011, 515-294-5247.