Building better soils through cover crops

Shay Foulk, Marshall-Putnam FB board member and field day host, discusses each of the species in the cover crop demonstration plot, including potential benefits, growth and termination patterns, and other tips for cover crop success. (Photo by Raelynn Parmely)

Start small, set goals and expect challenges with cover crops, farmers were told during the Marshall-Putnam Farm Bureau Nutrient Loss Stewardship Field Day.

Following this advice, farmers who implement cover crops can build better soil in their field — from physical construction to microbial communities — and reduce nutrient loss through improved water retention and decreased erosion.

This event, held near Sparland, was part of Illinois Farm Bureau’s (IFB) Nutrient Stewardship Field Days, which share ongoing research from the IFB Nutrient Stewardship Grant Program. The Marshall-Putnam Field Day presented information from a multi-year cover crop demonstration project led by a local farmer, Shay Foulk.

“Practices such as cover crops are helping us reduce nutrient loads and meet the goals of the Nutrient Loss Reduction Strategy,” said Austin Omer, Ph.D., IFB associate director of natural resource policy. “When it comes to these on-farm practices, farmers are leading the way.”

Cover crops are one in-field practice helping Illinois farmers reduce runoff and erosion. Also, cover crops can improve a farming operation in several ways. Illinois State University graduate student Emily Hansen shared her research on the microbial community in the soil and what impact cover crops have on that community. Microbes are essential to soil and plant health. They make nutrients available to crops and provide beneficial bacteria. Each cover crop has the potential to create a unique microbial community in soils.

“Plant diversity is directly tied to soil diversity,” said Hansen. “Planting any cover crop is going to help. Each type of plant adds different microbes to the soil that can lead to overall soil health improvements.”

Farmer attendees had the opportunity to see six different cover crops that had nearly six weeks of growth: cereal rye, oats, oat/radish mix, oat/radish/red clover mix, triticale and wheat.

Foulk, a farmer and ag business consultant, coordinated the plot and provided a walking tour. He explained the various benefits and challenges to each type of cover crop featured in the demonstration plot.

“One of the benefits of having the demonstration plot is you can actually see what it looks like growing in the field,” said Foulk.

Cover crops reduce the impact heavy rainfall has on soil and also slow runoff from rain and snowmelt. Both help to reduce nutrient loss. In addition, cover crops also store nutrients until they can be used by a future crop.

As part of this hands-on event, a soil pit was on-site for attendees to see how cover crops affect the soil below ground. Andrew Margenot, Ph.D., assistant professor in the Department of Crop Sciences at the University of Illinois, highlighted the types of soil and how various farming practices such as cover crops have impacted the physical profile of the soil in the field.

“The soil’s physical profile is improved for erosion and capture when cover crops are introduced,” said Margenot. “Not only can the soil capture more nutrients when cover crops are incorporated into the cropping system, but things like water and air can move through the soil more easily.”

Margenot added that tillage reduction can also improve soil structure. He underscored the benefits of using cover crops to break up compaction, reduce erosion and improve water holding capacity of soil.

Building better soils through cover crops

Andrew Margenot, Assistant Professor, University of Illinois, demonstrates cover crop growth below ground through use of a soil pit. This provided attendees an opportunity to learn more about Illinois soil types and the potential soil health benefits that cover crops can provide. (Photo by Raelynn Parmely)

A farmer panel then shared their experiences implementing cover crops. Across the board, the five farmers are having success with this practice. But it hasn’t come without obstacles, including terminating cover crops and having time to plant cover crops. The group noted that they focus on using cover crops in fields near watersheds or where additional erosion control is needed. They agreed cover crops are the right thing to do to care for their farms and for the environment.

“Cover crops can be tricky, but the net result is positive on my farm,” said Josh Merdian, a farmer who took part in the panel and also serves as treasurer of Marshall-Putnam Farm Bureau. “We’ve implemented cover crops because there is a lot of good research on how they improve soil structure, erosion control and soil microbes. We continue to see benefits year after year.”

As this project, demonstration and field day showed, cover crops are one more tool farmers can use to improve their farm and reduce runoff.

“Farmers who want to get started with cover crops should start small and find what works for their operation,” said Foulk. “Ultimately we need to try new things and see how we can work together as the farming community to reduce nutrient loss.”

To read more about IFB’s nutrient stewardship field days, visit www.ilfb.org/fielddays.