Fall Planted Cover Crops Can Break a Corn Soybean Rotation and Improve Soil Health

 As the combines start rolling across the country farmers are focused on taking the crops off the land.  However, it's a great time for farmers to also be thinking about planting cover crops to help them improve soil health.    

Anthony Bly is Soils Field Specialist at South Dakota State University and also a farmer that has used soil health practices for 30 years.  He says there are various late season cover crops farmers can plant, depending on their goals and climate.  "We have to think about where we're at as well, what latitude we're at and how much time we really have left to work with."

He says for farmers in a corn soybean rotation it’s a little more challenging to get a cover crop planted but they can look at winter annual grasses like wheat, winter triticale or cereal rye.   "Rye would be an awesome cover crop to fly in on corn at physiological maturity. Catch some rain so that crop can germinate on the soil surface and be there next spring. What a great tool for managing water."

Bly plants a 12 way mix on his own farm.  "I have brassicas in there. I have legumes in there I have a few warm seasons, just a couple, two of the 12 or one season, but predominantly all rest are cool season species. And I've got every one of them in there for diversity."

And he selects each cover crop species with a specific goal in mind for example flax. "Science has shown that flax really forms mycorrhizae associations on its roots. So, it promotes mycorrhizal fungi development as well."  

But he also has rooting cover crops.  "It's good to have a diverse rooting community and not have all tap roots or all fibrous roots, but a diverse mix of all of those root styles.  So, I have the radishes and turnips in there."

Those and other species also help build organic matter and carbon in the soil. "The brassicas and turnips and the broadleaf crops, legume crops promote breakdown of crop residues. And so, I need more carbon, so I'm going to be a heavily into carbon cover crops."

Checking his fields prior to harvest Bly sees first-hand the benefits of his soil health system including the below ground activity such as nightcrawlers.

"So, the biological life is cycling crop residues and that's a great thing because we know what that cycling there's nutrients that become available for the following crops.

The Conservation Technology Information Center is providing technical assistance to farmers participating in the Farmers for Soil Health program in Wisconsin, Minnesota and South Dakota. 

Jerry Schmitz, Executive Director, South Dakota Soybean Association says the program is devoted to increasing the usage of cover crops on corn and soybean acres. "We are educating and will help to implement in any way that we can. And that means mainly information. But we want it to be cover crops is going to be the huge focus and how to utilize those what works, what doesn't, and whether it work on your farm or not. Those are the types of things we want to get into," he says.

Schmitz says cover crops can be tricky to incorporate into a farmer’s rotation but have long term benefits.  "From generation to generation. Everybody's trying to do their best to protect the soil. And there's not one answer to that. Every piece of ground is different. And we need to focus on what's important to that family. They know the ground best, what can we do to assist them on achieving the goals."

The program is being funded by Climate Smart Commodity grants from USDA and will also provide payments for new and existing cover crop users.  The goal is to sign up 30,000 acres of cover crops in South Dakota during the first three years of the program.