The economics are there to justify growing cover crops. And even if you can’t measure the benefits directly the first year, you can measure them over time. If your soils aren’t the most productive in Indiana, cover crops offer an opportunity to help rebuild soil organic matter.
That’s why Mark Kingma uses cover crops on up to 80% of his acres. Kingma, Demotte, farms in the Kankakee River basin, and is familiar with sandy soils. “Where I burned down cover crops this spring, the commodity crops simply looked better. I’m confident I can get my money back out of what I spend on cover crops,” he says.
There is a caveat, however. Kingma says it may take a few years before you begin to see the kinds of benefits he sees now, after being in the system for a while. He is a no-tiller and began experimenting with cover crops in 2010.
“We’ve been no-tilling for 30 years,” he notes. “We’ve seen our organic matter levels increase about 1 percentage point every 10 years in no-till.”
Here’s an example. If organic matter content is 1.5%, then in 10 years it could build to around 2.5% with the help of no-till. You can expect to see the most improvement in soils that were low in productivity in the first place. That includes many of Kingma’s sandy soils.
What adding cover crops does is speed up the process of rebuilding organic matter, he believes. “I’m confident we’re going to build organic matter faster where we add cover crops with no-till compared to where we just no-till without using cover crops,” Kingma says. “My soils are more productive today than they were 30 years ago. For the most part, in my case, we are talking about sandy soil types.”
Kingma also observes that when he first farms a field that has been in conventional tillage and converts it to no-till and cover crops, he sees significant improvement.