Increased earthworm populations, fertilizer and equipment savings are positives Minnesota farmer Tom Muller sees from continuous strip-till.

Tom Muller, who farms a 2,600-acre family farm in Windom, Minn., is someone who can be considered an early adopter of strip-till in his area.

With help from his brother Steve Muller, and neighbor Paul Turner, he built his first strip-till rig in 1994, and has used the last 20-plus years to evolve his equipment setup and fertility program. He says he’s been reaping progressive soil health and yield benefits along the way.

“Our corn yields have gone from somewhere around 150 bushels per acre to around 170 since moving to strip-till,” says Muller. “I’m guessing a lot of that is seed genetics too, but our soil is getting healthier the longer we do this.

“We don’t always get really high yields, but we get good ones every year, and that’s what the banker likes to hear.”

Equipment Evolution

Muller was forced to build his own strip-till rig to start because there wasn’t much of that equipment on the market at the time, he says. But his equipment has gone through a fairly rapid transformation in the last several years.

“We found the row units, but had to build a toolbar,” he says. “We had to find a fertilizer hopper too, and we got it from one of the creators of Montag Mfg. I’m sure we were one of their first buyers.”

Windom, Minn., strip-tiller Tom Muller has found that worms are far more likely to make use of residue if it’s left on the surface, rather than being buried by tillage. He’s noticed that by building strips in the fall and leaving the rest of the residue undisturbed, the space between rows are often left bare by mid summer — everything having been pulled down by earthworms.

About 10 years ago, Muller entered into an arrangement with his local co-op, Country Pride Services Cooperative. The co-op purchased its own Blu-Jet 24-row strip-till rig and offered members a per-acre custom rate on their fields.

“I don’t know that there are many co-ops out there that do that, so we’re privileged,” says Muller.

He admits that the cost is considerable, but the efficiency and time-management benefits that he receives validate the price. The biggest advantage, he says, is the savings from not having to purchase the equipment himself.

“We only need two medium-sized John Deere tractors for planting, spraying and pulling the grain cart,” says Muller. “We don’t have a moldboard plow, a disc ripper or a big 500-horsepower tractor.”

In addition to the savings on larger equipment, the savings on labor, fuel and existing equipment wear-and-tear help further justify the expense of having his co-op build his strips.

“We put less hours on our tractors now,” says Muller. “We farm 2,600 acres using only 2,000 gallons of diesel fuel storage, filled up once a year. In labor, when we’re done combining a field, we’re done. We can skip building the strips ourselves and go on to the next field and harvest more acres — that’s where the income is.”

The only minor issue Muller has found is syncing the John Deere GreenStar RTK running on his 24-row John Deere planter with the Ag Leader RTK system the co-op uses on their strip-till rig. But his experience using only markers when he started strip-tilling has made this issue manageable for Muller.

“It helps that our planter matches their strip-till rig in the number of rows,” says Muller. “We just have to drive our first pass with the corn planter on the strip and set the A-B lines. So the worst thing that might happen is having to do it again, or push the arrow on the screen to sort of adjust it a bit.”

‘Drought Proofing’ Soils

In his rotation, Muller no-tills soybeans and strip-tills corn, usually at a 50% split on acreage. He says running the two practices in tandem for many years provides an opportunity to see how they impact soil health and structure in the long term.

Tom Muller, veteran strip-tiller in Windom, Minn., talks about and shows the benefits of strip-till in promoting earthworm activity in his fields and improving soil structure.

One example is moisture retention, and Muller says he only needs to glance at his neighbor’s conventionally tilled fields to gauge his results.

“We’re at a point where we’re almost drought-proofing our soils,” says Muller. “Not 100% proofed, but when we’re driving down the road in the heat of the summer and it hasn’t rained for a while, our corn takes at least three days longer before it starts wilting than the farmer who is doing conventional tillage.”

Additionally, Muller says he’s less concerned about doing field work sooner after a significant rainfall, citing soil structure built by no-till and strip-till practices that keeps mud from collecting on his tires during a wet fall. He also notes improved soil structure prevents a plow pan from developing in the deeper tiers of the soil profile.

“The guy who does our tiling always praises our soil and says that he can shift up a gear because it pulls so easy for him,” says Muller. “We’ve seen development in soil structure that’s down deeper as well. We don’t need to use a V-ripper to try to tear it up.”

Worms Do the Work

Muller notes that creating an ideal seedbed and limiting compaction in his silty clay loam soil is only half the story. Any given clump of his soil is bound to contain evidence of healthy worm activity, which is something he says is paying dividends.


Muller’s soil structure and health is such that, he finds evidence of earthworm activity in practically any given clump of soil. He says that he doesn’t have to go far to find holes, tunnels and worm castings in his field, all of which help with fertility and water infiltration.

“I would guess that it took about 5 years of strip-tilling for the soil to really start changing,” says Muller. “The worms are incredible. They’re doing some serious soil turning for us. We have a lot of residue when we plant in the spring, but by the middle of the summer, it’s bare between the rows. The worms pull everything down.”

Muller says that the worms are far more likely to make use of residue if it’s left on the surface, rather than being buried by tillage.

In his fields that haven’t been tilled for many years, he’s created a favorable environment for worms, and Muller suspects it’s also reduced the spread of soybean cyst nematodes. He notes that many local farmers have been afflicted with these nematodes to a point where they’ve stopped growing soybeans, due to yield drops.

Muller says the infestations show up in hotspots in his fields, and strip-tilling treats those spots more delicately.  

“We don’t have as many soybean cyst nematodes because we’re not dragging around those eggs and moving them,” says Muller. “When you pull a heavy tillage implement through a hotspot, it will spread the eggs and infect the whole field. Our hotspots stay small.”

Monitoring Fertility

Muller says he follows the University of Minnesota’s fertilizer recommendations rates pretty closely, but the added control of applications through strip-till lets him alter his program slightly.

Muller has reduced the amount of anhydrous ammonia (NH3) they apply in the fall, down to about 100 pounds per acre, while also applying some in the spring.

“We’ll put a little bit of pop-up fertilizer down with the planter, and about 60 pounds per acre of 32% nitrogen with herbicide broadcast in the spring,” he says.  “We are also using nitrogen stabilizers.”

During fall, he applies 50-60 pounds per acre of both diammonium phosphate and potash with the strip-till unit, banded about 4 inches deep. He’s found that there is some wiggle room in these rates as well.

“Because I’m putting fertilizer right where the corn roots are, when things do get tight and there’s not a lot of income to play with, I can scale back my P and K rates and still be okay,” says Muller. “Whereas, if I cut back on a broadcast program and that’s all I had, it would hurt.”