The 2011 season was another tough one from the standpoint of having enough nitrogen at the corn plant's disposal when it needed it most to plan and deliver high yields. Part of it related to the wet spring that caused some N losses on N that had already been applied. Some of it tied to the inability to get postemergence applications on exactly when you wanted due to rains after planting. Then the water from the sky shut off and many things went wrong, sometimes including not having enough N available.
One of Betsy Bower's jobs is to assist farmers she works with on forming a N plan that makes sense for them. She's an agronomist with Ceres Solutions, Terre Haute. She also coordinates the Crops Corner and Hoosier Bug Beat columns in Indiana Prairie Farmer on behalf of the Indiana Certified Crop Advisers. Three CCAs each issue answer tough questions of the day, such as designing effective N management programs. The panel rotates on a three-month basis to get fresh ideas into the program. Bower is one of the panelists for the winter issues.
"We don't want corn to suffer from N deficiency at any time of course, but the corn plant needs to see enough N at ear determination time, during the grand growth phase as it builds the stalk and after pollination as it fills the ear," she observes.
"At times with the weather patterns we have been experiencing the past few seasons, it has been challenging to keep enough nitrogen there for grain fill."
That's true even if you use N-Serve for anhydrous ammonia applications of N or Instinct in liquid applications. Both are nitrification inhibitors from Dow AgroSceince. They are typically used in pre=-plant situations where the total N load is applied pre-plant, and sidedressing is not part of the program.
Last year Bower noticed that fields where N-Serve or Instinct were used in pre-plant applications of N were better yielding than fields where those products weren't used in N applications before planting. However, she believes those fields could have possibly yielded even more with split nitrogen application programs. In these programs, some nitrogen would likely be applied after planting and when corn is up.
See complete answers form Bower and two other CCA members on this subject in the February issue of Indiana Prairie Farmer.