June 30, 2025

Beyond the bottom line: Cover crops, no-till offer other benefits

EARLVILLE, Ill. — Two year’s of data collected by a LaSalle County farmer found that his no-till and cover crop system reduced fuel and input costs while keeping yields at or better than a conventional tillage practices with no cover crops.

Beyond the bottom line, Carl Zimmerman said in an Illinois Sustainable Ag Partnership-hosted risk management webinar, the no-till and cover crop system provides other benefits.

The benefits beyond the budget that he found included increased soil aggregate stability, increased load carrying capacity, increased water-holding capacity and an increase in biological activity has led to increased residue degradation.

Using the shovel test, Zimmerman counted 23 earthworms in one spade pull from no-till and cover crop ground and just two earthworms in a sample pull from farmland that was conventional-tilled and no cover crops.

Less Variability

Zimmerman is also finding less variability in yields.

“Many are talking about how the yields increase (in no-till and cover crops). Yes, the yields are increasing, but it’s not so much the better areas that are increasing. We’re removing a lot of our variability in some of the underperforming areas,” Zimmerman explained.

“We’re getting that ground to breathe better using cover crops. We’re bringing up fertility from years gone by or unlocking the fertility that’s still in the ground. When we combine we’re seeing a lot less discrepancy in our yield maps as compared to before cover crops. Yes, our yields are increasing every year because of that.

“You can have the best part of the ground that’s correctly tiled and everything and if you do cover crops you’re probably not going to see that huge of an increase. But in your poorer ground, your less well drained ground, you’re going to see a tremendous increase.”

Weed Control

The use of cover crops has also reduced weed pressure in Zimmerman’s fields to the point where the last two years only one herbicide application pass in cereal rye was needed.

“Waterhemp is a big issue around here. With dicamba being taken away, we’re going to have to do something. There’s really nothing new in the chemical pipeline that’s coming down to combat some of these weeds. Let’s work with Mother Nature instead of working against her. We’re going to put the covers out there and cover that ground up,” he said.

“Whether it’s due to decreased germination because of more moisture, maybe the ground is a little cooler or some believe in the natural toxins like cereal rye puts out that helps keep some of these weeds at bay. Whatever it is, it works. Anywhere we can get rye established, we don’t have a problem with weeds.”

Zimmerman said the biggest challenge has been establishing cover crops in field wet holes and they’re going to change it up a bit this year to see if it helps.

“We’re going to double-back and probably double the amount of cereal rye anywhere from 100 to 120 pounds in those wet zones where water washes across from maybe a neighbor or a ditch because where we have problems with waterhemp is in those areas. They’re very small spots and we can go out with a Ranger and take care of them all,” he said.

Start Small

For those considering the cover crop and no-till system, Zimmerman recommended to start small with 10 to 20 acres. He started with 40 acres and has since built the system up to 1,600 acres in seven years.

He added that it’s best to make a long-term commitment.

“Don’t expect the same results every year. Look at the overall big picture and what it’s doing to your soil health, weed pressure and fertilizer. Maybe we can start taking a little nitrogen or phosphorus and potassium away from that area and not see a yield hit,” Zimmerman said.

“Remember this is a journey, not a race. We learn more every year. Figure out what works for you and put it to use because another thing that’s more than likely going to happen in the years to come is regulations. We’ve already seen it in the Chesapeake Bay area where they have to have a plan for their fertility management.

“We’re located in the biggest watershed in the United States — the Mississippi River. It’s not a matter of if; it’s a matter of when we’re going to have to have everything verified.

“Why not get started early, that’s been our attitude. Let’s show the legislators that we know what we’re doing. We are starting to test for nitrates out of our tiles, we’re implementing cover crops, let’s beat them to the punch on it.”

He recommended talking with local farmers who have had success with their no-till and cover crops system, and also plan ahead with a herbicide program to ensure success with the cover crops.