Question: If you don’t have access to side-dress equipment, what would be the best alternative in a corn-on-corn rotation to minimize nitrogen tie up and grow the best corn crop possible?
Answer: Depending on what part of the country you are located in the issue of residue breakdown may vary. In general, growing corn on corn from the mid-U.S. to the north. residue break down is slower due to cool temperatures. Corn on corn grown in the south will have less of an issue, since warm temperatures help to break down the corn on corn residue. In central Illinois and the eastern and northern Corn Belt, we typically recommend 100 lbs N/ac (may be different in your area) to be applied up front to handle the carbon penalty in corn on corn. These 100 lbs should be a mix of broadcast nitrogen and starter fertilizer, the remainder of the nitrogen needed for the corn crop is then sidedressed. In your situation, where sidedress is not possible, starter fertilizer could play a more important role for applying N (in addition to P). Applying nitrogen in a 2x2 band along with your phosphorus will help. Depending on your soil type (rates will vary), consider applying a portion of the nitrogen with the corn planter in a band at least 2x2 away from the seed. I would still recommend some broadcast nitrogen pre-plant in addition to the starter to help break down residue. The remainder of your nitrogen needs could be applied pre-plant broadcast or banding, depending on the source. Consider using a stabilizer product for this application. Another option would be applying UAN with the corn planter between 3 and 4 inches away from the seed at higher rates; however you would want a closer placement for the phosphorus. Some growers that do not have a sidedress bar, have applied UAN sidedress with a sprayer set up with drop nozzles in-between the rows. A stabilizer to prevent volatilization would be very important here.
This blog is provided as an interactive way for you to have your questions answered by our Farm Journal Agronomists. E-mail your nitrogen, soil fertility, soil density, planter set-up, scouting, and other questions to: TestPlots@FarmJournal.com
