If you apply fertilizer based on estimated corn yields, you may be using too much nitrogen.

According to research from the USDA’s Agricultural Research Service (ARS), the “yield-goal” method often used to estimate fertilizer use is a poor indicator of how much nitrogen to apply to fields. That’s because it’s difficult to predict yield months in advance of harvest. Plus, this procedure doesn’t account for weather conditions throughout the growing season or soil variability within fields — two factors that affect yield.

Therefore, ARS researchers are exploring better ways to determine which is the most optimal fertilizer-application rate. One method under development is a canopy-reflectance sensor that monitors crop vigor, thereby estimating just how much fertilizer the corn needs. If application rates could be based on techniques like this, it could result in less fertilizer use — and savings to your bottom-line.


Go to: www.ars.usda.gov/is/pr/2004/040629.htm