Many growers have already applied all or a portion of their nitrogen for this year’s crop. In many areas, a warm and wet November-December, in connection with an early warm-up this spring, has led to conversion of the NH4+ molecule to the NO3- molecule, making it more available to leach or to be denitrified, depending on the soil type, texture, and drainage profile of your fields.
A recent article (April 8, 2016) in the?University Illinois Crop Bulletin* highlighted some test results found after testing eight fields in Vermillion County, Illinois. In the chart, you will find the summarized results, indiciating the portion of anhydrous that has been converted. As you can see, the tests run on January 5 found 93 pounds of nitrate in the top 2 feet of the soil profile.
So what are the implications? Right now, there could be a significant amount of fall-applied N in the nitrate form. It could also mean that as your crop is moving into the growth phase later in the year, when high levels of nitrogen are required, your fields might experience a shortage (if conditions lead to high denitrification or leaching) unless you take some steps to remediate the issue. What are those steps?
- Measure:Use a 360 SOILSCAN™machine in-season to measure the conversion and availability of NO3- nitrogen to your crop. You may discover that your original plan now requires changes in order to reach your maximum yield potential.
- Modify: Adjust your plan by understanding the potential remaining demand of the crop and modify your nitrogen application strategy to meet that demand.
- Wait: Let the spring weather play out – flushing rains or mineralization – so you are familiar with the nitrate levels heading into the reproductive stage.
- Apply: Utilize technology to apply the needed nitrogen to coincide with the timing in the corn plant’s life that will satisfy the crop needs in order to maximize nitrogen efficiency and the field’s potential.
While each regions? weather has been different, you should be cautious about nitrogen levels heading into planting. Although you may have experienced weather conditions that have created a potential issue in your fields, the good news is that there is still a chance to rectify the issue utilizing the measure, modify, wait, and apply approach to maximize your results at harvest.