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Illinois Soil Nitrogen Test

What is the Illinois Soil Nitrogen Test?

The “Amino Sugar N Test”, or the “Organic N Test.”

 

The Illinois Soil Nitrogen Test is an innovative nitrogen test developed at the University of Illinois. This test measures a soil’s ability to slowly provide nitrogen to the crop during the growing season. The analysis looks at the organic portion of the soil, particularly at compounds called amino sugars.
Measuring the amino sugar parts of organic matter gives an indication of potential release of nitrogen from the soil.  Research has shown that many agricultural fields receive more nitrogen than needed to economically optimize yield. It is not uncommon for 60 to 80 percent of the nitrogen used by the crop to be provided by the soil during the growing season through mineralization.  (Mineralization is the term applied to microbes dissolving the minerals in the sand and rocks in the soil and delivering them to the plant roots. ) The remaining nitrogen needs are met through applied fertilizers. The ISNT will allow you to apply less nitrogen fertilizer where the soil has a high ISNT value.  In many fields with high ISNT organic nitrogen levels NO SYNTHETIC NITROGEN FERTILIZER is needed.
In simple language, biologically active soils resulting from Regenerative Agriculture management may NOT REQUIRE or need very little synthetic fertilizers to produce high crop yields.  This ISNT test can measure and determine the organic nitrogen in the soil and guide the level, if any, of synthetic nitrogen fertilizers needed.
Likewise, the benefits of BEAM usage can be determined by comparing levels of available organic nitrogen (with the ISNT testing) before BEAM and after BEAM application.
Most older soil testing methods do not accurately measure levels of soil derived organic nitrogen and farmers are wasting vast amounts of dollars for unnecessary fertilizers.  

How is this test different from nitrate testing?

One limitation of the nitrate test is the inability for the results to be used for multiple growing seasons. A nitrate test is only a snapshot of the nitrate levels in the soil at that exact moment in time. Nitrate levels can fluctuate due to water movement, denitrification, mineralization, crop uptake, and other factors.

Levels of nitrates in the soil can change greatly between years and during the growing season, therefore nitrate testing needs to be repeated before each corn crop. The ISNT measures a portion of soil organic matter that acts as the source of the plant available forms of ammonium NH4 and nitrate NO3. This test gives growers a measure of how much nitrogen can be expected to be released during the growing season.  The ISNT can be valid for a number of cropping seasons before having to repeat the test.
 CropSmith,  is the laboratory doing this test and uses the same methods as the Uni. of Illinois.