Soil specialists at the University of Minnesota Extension offer the following to help you make nitrogen decisions. Heavy rains have threatened N supplies in the soil and if your tile lines are spewing water, chances are, your soil will experience some degree of N loss. We advised just today that N demand is expected to ramp up through June and prices may follow that demand. Given that, growers should book supplemental N needs before prices have a chance to increase.
The article below offers a calculator to help figure how much N may have been lost and some good insight to guide your decision making process...
When it rains, it pours! What is happening to my nitrogen?
By Daniel Kaiser on May 29, 2012
John A. Lamb and Daniel E. Kaiser
Soil Fertility Specialists
Nitrogen is important for corn growth. This has been a concern on growers' minds since March. First concern was with the poor tillage conditions last fall. Did the nitrogen applied stay in the soil. We attempted to answer that question in a March 18 E-news. At the time of that E-news, drought was the weather condition on everyone's mind. Now with the record rainfalls, there are concerns if nitrogen has been lost to leaching or denitrification.
How Do You Assess if Leaching or Denitrification can be a problem?
One of the first things to look at if your field is tile drained, is if there is water draining from the tile. If not, then it is more than likely the soil was dry enough before the rain to store the water. The nitrate in the soil profile may have been moved deeper in depth but it will still be available for plant use. There is not enough water to cause the anaerobic conditions needed for denitrification to occur. If the tile line is draining water, then there is a chance that the soil is water logged. There may be some chance of denitrification but if water is standing and soil temperatures are greater than 50 degrees, then denitrification can and will occur.
How do I assess the amount of N that is available to the corn plant?