Interested in diversifying your cover crop mix or exploring the power of clover cover? Episode 61 of the Illinois Nutrient Loss Reduction podcast looks into utilizing clover as a cover crop with Adam Dahmer, farmer from Williamson County in southern Illinois, and Nathan Johanning, Commercial Agriculture Educator with the University of Illinois Extension.

A farmer’s perspective

Adam Dahmer, a sixth-generation farmer from southern Illinois located in East Marion in Williamson County, has a deep-rooted commitment to conservation. Dahmer's cover crop journey began in the late '90s when his father recognized the need to increase organic matter on their land. To begin, they started with cereal rye, planting it via airplane and interseeding it with standing corn. Over time, he has attempted various other planting methods, including utilizing drones and building a custom cover crop seeder from a high boy sprayer. Ultimately, Dahmer discovered that drilling his cover crop had the most success through better stands even if it does take more time. By 2012, Dahmer transitioned to a 100% cover crop and no-till system, incorporating a diverse mix of species before corn such as:

• winter oats,  
• rapeseed,
• annual ryegrass,
• crimson clover,
• and hairy vetch depending on the outcomes desired for the field.

Dahmer also uses a diverse mix before his soybean crop that includes:

• cereal rye,
• rape seed,
• and hairy vetch.

He says that sometimes he replaces vetch with crimson clover because hairy vetch can create a thick mat that may impact soybean emergence.

Impact of cover crops

The only regret that Dahmer has is that they did not start planting cover crops on 100% of their acres earlier due to the transformation they have observed in their soil health and resilience. The improvements that they have seen have been so impactful that Dahmer said he won’t go without cover crops on his fields. 

He explained that challenges happen, and you can always find an excuse not to implement cover crops, but with the right program and resources including a knowledgeable and experienced cover crop seed dealer, a field can be transformed in three to four years. Dahmer shares that they recently acquired a farm about half of a mile from their home farm that was farmed the same but hadn’t adopted any of the conservation practices that he has implemented. There has been a 40-bushel difference in corn yield between his home farm and the new farm. Dahmer attributes the higher yields to the soil structure, better water holding capacity, and decreased compaction on his home farm that comes from adopting cover crops and no-till.

Clover research

On the research front, Nathan Johanning provided insights into ongoing cover crop studies he is leading throughout Illinois discussing his research with the University of Illinois Extension. One focus of his research is on understanding the impact of planting dates on cover crop performance looking at clover ahead of corn and cereal rye ahead of soybeans. Johanning is studying cover crop strategies for maximum biomass production and crop yield. A key aspect of Johanning's research revolves around crimson clover and balansa clover. Johanning explains that these legumes offer nitrogen fixation benefits while enhancing soil health and diversity with a lower C:N ratio in the biomass. Johanning’s research looks closely at different types of clover, studying how well they grow and adapt to different planting conditions. 

Cover crop advice

Dahmer provided some practical advice for farmers interested in planting cover crops or diversifying their cover crop mixes. Dahmer emphasized the importance of being open to change and continuous learning in these systems. He also highlights the significance of adapting equipment and practices to suit the needs of cover cropping. From adjusting planter setups to rethinking nitrogen application methods, Dahmer's experience and advice reveal the necessity of a tailored approach when planting cover crops.

Furthermore, for farmers looking to diversify their crop mix, Johanning stresses the importance of utilizing regional resources and tools like the Midwest Cover Crop Council's selector tool to tailor cover crop selections to local conditions. From understanding planting windows to selecting suitable species, Johanning's guidance empowers farmers to make informed decisions about cover cropping.

To hear the complete interviews with Dahmer and Johanning, check out podcast episode 61.

Learn more about nutrient loss and conservation by checking out the Extension Nutrient Loss Reduction website, live and available at extension.illinois.edu/nlr. 

About the authors 

Rachel Curry is an Agriculture and Agribusiness Educator focusing on agriculture and watershed education and is a part of the Illinois Extension's Nutrient Loss Reduction Strategy implementation team. Rachel earned a B.A. in Environmental Studies from Knox College and an M.S. in Environmental Science and Soil Science from Iowa State University with an emphasis on soil fertility. Her work focuses on education and outreach regarding the Illinois Nutrient Loss Reduction Strategy and agricultural conservation practices to reduce nutrient loss and improve water quality and soil health throughout Illinois. 

Nicole Haverback is a Watershed Outreach Associate and is a part of the Illinois Extension's Nutrient Loss Reduction Strategy implementation team. Nicole earned a B.S. in Agriculture and Rural Policy Studies from Iowa State University. She coordinates watershed and planning activities to reduce nutrient losses from priority watersheds, provides expertise on best management practices for nutrient loss, and conducts outreach on agricultural conservation practices outlined in the Illinois Nutrient Loss Reduction Strategy.  

Emma Eldridge is a Watershed Outreach Associate and part of the Illinois Extension Nutrient Loss Reduction Strategy implementation team, serving the Little Wabash and Embarras watersheds, designated as phosphorus-priority watersheds in the NLRS. Emma earned a B.A. in Environmental Studies from McKendree University and an M.S. in Forestry from Southern Illinois University Carbondale. She coordinates watershed and planning activities to reduce phosphorus losses from identified priority watersheds, provides expertise on best management practices, and conducts outreach on agricultural conservation practices outlined in the Illinois Nutrient Loss Reduction Strategy. 

About the blog 

At Illinois Extension, we’re working to improve water quality at home and downstream. Every month, our Watershed Outreach Associates will bring you stories highlighting agricultural conservation practices, current research projects and results, and from the field farmer interviews. The Nutrient Loss Reduction blog covers conservation practices recommended by the Illinois Nutrient Loss Reduction Strategy, timely updates, farm safety, and new decision tools to help farmers and producers reduce the nutrients leaving their field. Want to get notified when new blog posts are available? Subscribe at go.illinois.edu/SubscribeINLRS.