For crop farmers, research is a year-round task. They have to find the best seed to match their soil, determine the right amount of fertilizer to maximize their yield and get their crop in and out of the ground at the right time.

The South Kinnickinnic Farmer-Led Watershed Council set out to inform local farmers of fertilization optimization practices and learn more about local soil during the March 24 annual meeting at The Ridgetop.

River Falls seedsman Keith Gunderson presented soil testing results on a pair of area farms, carving out blocks of land to test low, medium and high fertilization applications. What they learned, as a University of Illinois professor also discussed at the meeting, was that nitrogen quantity in the soil and the nature of the soil was the difference maker in the amount of fertilizer required. Test yields remained fairly steady through low, medium and high application amounts.

“We thought we would see low [application] be the lowest yield at all times, the high being the highest yield all the time. We’ve definitely seen that soil type makes a big difference out there,” Gunderson said.

Illinois Professor Richard Mulvaney was a guest speaker at the meeting, discussing nitrogen in soil, how it is made available and how it is used by crops.

“The key players from a standpoint of making soil N available would be the bacteria, the actinomycetes and the fungi that mineralize organic substrates,” Mulvaney said. “They know their business, and they are the disposal team that breaks down the residues and recycles nutrients.”

Mulvaney said soil at some sites features a lack of N, meaning it requires a higher dose of fertilizer. Soil at other sites is able to provide the necessary nutrients, meaning fertilizer doses can be redundant.

“For me, this is kind of a jaw-dropper, because we’re talking about a recommendation system that is based on expected yield, but there is no relation between yield and optimum N rate. It just doesn’t connect,” Mulvaney said. “It’s because there’s another N source the crop is using. It’s from the soil itself.”

During the question and answer phase, Mulvaney was asked about the use of anhydrous ammonia, one of the cheapest sources of N that may damage soil microbes.

“A lot of the ammonia used in Illinois is applied in the fall after harvest. That practice, you would think, would be environmentally detrimental, setting the stage for N losses. You’re right that it does affect the soil microbes, but I will have to tell you, from another series of studies that I did not talk about comparing the uptake efficiency of N with fall-applied anhydrous with in-season UAN [Urea Ammonium Nitrate] and they were on the same sites and some of the same growing seasons, we saw no difference. In both studies, the soil was the key factor that affected uptake efficiency.”

Mulvaney said he prefers less drastic sources of nutrients, but if it is applied, it is better to do so closer to the growing season.

The Council is one that focuses on sustainable practices for farmers while finding ways to maintain strong yields. There are a list of provided incentives where farmers can earn money for checking certain conservation boxes including maintaining a nutrient management plan, growing cover crops and much more.

“I wouldn’t say our council was formed because of a problem. I think it was formed because we just had a bunch of like-minded people that thought we could do better,” Conservation Engineering Technician Dan Sitz said. “The sky is the limit, really.”

More information on the council is available at farmerledwatershed.org.