A USDA Agricultural Research Service soil scientist has developed a more accurate test for how much fertilizer a farmer needs to add to a field, reducing costs by $10 to $15 per acre and diminishing run off.
Richard Haney, with the Grassland, Soil and Water Research Laboratory in Temple, Texas developed a soil test that replicates some of the natural processes that occur in a field, accounting for microbial activity while measuring nitrate, ammonium (NH4), and organic nitrogen.
The new soil test is known as the Soil Health Tool. It involves drying and rewetting soil to mimic the effects of precipitation. It also uses the same organic acids that plant roots use to acquire nutrients from the soil. The tool measures organic carbon and other nutrients, accounts for the effects of using cover crops and no-till practices, and will work for any crop produced with nitrogen or other types of nutrient fertilizer.
Haney has made it available to commercial and university soil testing laboratories and has worked with farmers to promote it. Growers who use it receive a spreadsheet that shows the amounts of nitrogen, phosphorus, and potassium available to crops. On average, they reduce fertilizer costs by about $10 to $15 per acre. With less fertilizer applied, there is less of it running off into surface water.