How Flexible is Your Nitrogen Program?

Many of you know that we actually have a farm here at Peterson Farms Seed. Carl’s grandfather started farming here in 1918 and his dad followed in the 1940’s. We call it Carl’s Farm, and it is where we get to test new technologies on an actual farm.

This season, we wanted to put 360 Yield Center’s Y-Drop system to the test. The Y-Drop spraying system, which I cover in more detail here, is installed on a self-propelled sprayer, allowing in-season liquid applications.

The advantage of this system is the ability to reduce the amount of spring-applied nitrogen with the addition of one or two applications later in the season. Applying less N in the early spring allows for less risk of nitrogen loss due to denitrification and leaching. The longer window for application with the self-propelled sprayer allows for time flexibility when determining the right time and amount of nitrogen needed for the rest of the season.

First, we determined a lower base nitrogen rate to apply pre-plant in the spring. Traditionally, farmers estimate a yield goal and apply all the fertilizer for the season in one shot. The full season rate would equal around 200 lbs of actual nitrogen. This season, we dropped our pre-plant nitrogen rate down to 113 lbs.

With our lower base rate of nitrogen applied, we tested different rates, timings, and double applications of nitrogen with the Y-Drop after the initial application. Refer to the table below for results.

The images to follow show the yield maps of Field A, B, and C. The black outlines show where the different applications took place within the field. Take note that these are large scale test strips (around 30 acres each) so there are a number of environmental conditions to be aware of including ditches, soil type, drainage, etc.

Field A:

Field B:

Field C:

Due to the size of these plots, the only significant difference from the average was the Zero Base+20gal Y-Drop in Field B at 186 bu/ac.

So, does this mean the Y-Drop system doesn’t work? Simply put: No. There is more to the story. In Cass County, we were blessed with great weather and perfectly timed rain events. How does this relate? Because of the great weather and the perfect amount of rain, we received free nitrogen due to mineralization of organic matter in our soils. From soil testing during the season and utilizing nitrogen monitoring software, we determined we received anywhere from 20-30 lbs of free nitrogen to finish off the growing season.

The next question that comes to mind is are all of these tests useless based on our results? Again, I would say no. We were able to learn more about the mineralization capacity of our soils when the weather was favorable to our fields. We also know that every year will not be like the last and we now have the ability to be flexible during the season with our nitrogen applications when mother nature isn’t as kind.

As always, if you have any questions about the testing we do on Carl’s farm or any questions related to the 360 Yield Center, give us a call at 701-282-7476.