Fall Nitrogen Management for Winter Wheat Crop

Joanna visits with Edwin Ritchey, University of Kentucky Extension Soil Scientist to discuss fall nitrogen management for the 2019 winter wheat crop. This past year was unusual compared to many due to weather conditions. Much of Kentucky had a wet spring, followed by a wet summer and some very good corn yields. However some of Kentucky was actually dry and had low corn yields. Most years the residual nitrogen remaining after corn harvest and that released from corn stalks is sufficient to provide the needed fall nitrogen to establish wheat. Too much nitrogen can lead to excessive fall growth and greater lodging potential. UK recommends to add no more than 40 lbs. N/A and most years the residual N coupled with DAP (18-46-0) will meet that need. This year additional N may be warranted. A soil nitrogen test may help determine the need for N if a producer is not sure. It is suggested to collect the sample to 12 inches in depth between corn rows. Nitrogen at this depth will be available for wheat growth. Most labs report nitrate, but some will also report ammonium. The results are in ppm. Every six inches of soil represents 2 million pounds of soil. To convert ppm to lbs. per acre on a 6 inch sample you need to multiply by 2, so a four inch sample will need to be multiplied by four to get pounds per acre in a 12 inch sample. If a 12 inch soil sample has 30 – 40 lbs. nitrogen/A then additional N should not be needed. Samples with high soil nitrogen values should be closely examined in the spring to make sure excessive N is not added in the spring application. For more information contact and follow us on social media. Warren County Cooperative Extension Service https://www.warrencountyextension.com https://www.facebook.com/warrencountyag https://warrencountyagriculture.com https://www.instagram.com/warrencoag