In Gaston, Ind., Jason Mauck is farming a little differently from his neighbors.
Unlike the typical corn-and-soybean monocropping system, for the last 5 years Mauck has been doing low population, wide-row relay intercropping. So far he has seen success with soybeans into wheat, but he’s also working on corn intercropped with a legume.
Inspired by the results he saw from interplanting and using low populations in the landscape business he started prior to farming full-time, his goal is to capitalize on sunshine, wheat and hog manure — annually Mauck has about 5 million gallons from his 25,000 finishing hogs operation. By growing crops in wide rows, sunlight is able to reach more of the plant, particularly its lower leaves, for greater crop production, while intercropping helps shade out weeds, keeps soil life active throughout the year and reduces input needs.
While the first couple years were a challenge, Mauck’s persistence has paid off. He’s now saving around $200 an acre on input costs, while increasing revenue through high-yielding soybeans — Mauck currently holds the state record for soybean yield per acre.
Here’s how the system works, and how you can implement it on your own operation.
Seed Wheat Early
For those following a corn-wheat-soybean rotation like Mauck, the relay intercropping system technically starts with corn when you select your hybrid. Mauck recommends using an early maturing hybrid so you can get the wheat in earlier and allow it to capitalize on tillers.
Last year he draglined manure and then planted his wheat in quad rows, 19 inches wide, on 60-inch centers. This leaves a 41-inch space for the soybeans.
Mauck recommends those who do a fall manure or commercial fertilizer application seed a cover crop that will winterkill to capture and hold onto the nutrients, as wheat’s root system isn’t big enough to do so. He prefers radishes because they make a quick canopy to capture sunlight. In Mauck’s location, the radishes will winterkill in January.
But Mauck will be moving toward a different setup in the future, as he’s developed a strip-till machine with Dawn Equipment that will apply biochar instead of raw manure with the seed. Biochar is about a half percent of the volume of manure and is mostly carbon, he explains.
Mauck charges the biochar in his hog barns, as it absorbs ammonia from the air. He then runs it through a mesh screen, which breaks it down into a powder, and mixes it with nitrogen and other commercial fertilizer. This provides a coating for his wheat seed, which it gets mixed with in the strip-till machine.
He says the biochar allows farmers to slow down nitrogen leaching while also preventing seed burn.
“You get a ton of ammonium you can put with the seed and it doesn’t have the salt burn that commercial fertilizer has,” he says. “It’s pure carbon.”
His long-term goal is to acquire manure from areas that are inundated with it to create more biochar and make it available on a bigger scale.
Keep the Rows Wide, Plant in Twins
To make this system work, you have to plant in wide rows.
“Solar corridor is king on intercropping,” Mauck says, explaining that the wheat will spread out as far as it possibly can to take in the sun. In a presentation for the 2019 Practical Farmers of Iowa Annual Conference, Mauck explained that when he grew wheat in 7.5-inch rows, with a 30-inch gap in between, that 7.5 inches turns into a 20- to 30-inch-wide group of wheat heads, resulting in 4 times as many wheat heads.
He explains that the wheat plants will compete with others for sunlight, and in those wider rows, this results in the crop forming a half circle — the outsides of the row will be shorter and jet out, while the middle of the row will be taller and grow straight up. This allows the crop to capture more sunlight and manipulate its growth, but only in wider rows can that half shape occur.
Wheat residue helps suppress weeds as the intercropped soybeans continue to grow. Wheat also allows Jason Mauck to plant his soybeans a month earlier than his mono-cropped soybeans. Photo by Jason Mauck.
In fact, the wheat spreads out so wide Mauck has gone from twin 30-inch center rows, to twin 37s, to twin 60s, widening the wheat row width from 7.5 inches to 19, to keep the wheat from closing the space where the soybeans will go.
Planting in twin rows is also important because the plants are too close together in single rows and will block the solar angles too much, Mauck says. While it’s possible to do single rows, it also takes away some of the economic advantages with wide, twin-rows. You’ll also likely have to plant later, which means you’re depending more on July and August rains instead of capitalizing on the moisture seen in early spring.
Reduce Your Seeding Rate
The main disadvantage with trying intercropping in single rows is that you have to increase the seeding rate to fill in the canopy in that individual row, which eliminates one of the input savings Mauck has reaped from the system.
Because the crops have more room to grow in the wider rows, Mauck has been able to significantly reduce his seeding rate. He recommends growers keep the same row population and just omit rows.
On his farm, he normally plants his wheat at 1.6 million seeds per acre when it’s monocropped. In the relay system, that drops down to 800,000, since he’s planting four rows on and four rows off. On his monocropped soybeans, which are planted in 20-inch rows, he seeds them at a population of 150,000, so omitting rows in the twin-row system drops it down a third to 100,000.
Despite the significant seed reduction, it doesn’t equate to the same reduction in yield.
“When you add those two crops together now, you have a similar seeding cost as seeding one crop,” Mauck says. “But planting half the plants doesn’t mean you’re only going to get half the yield. With soybeans you may get 98% of the yield. You’re getting more soybean seeds per plant when you seed less.”
Focus on Soybeans
The same is not true for wheat, however. Mauck says the key to economically succeeding with this system is to focus more on driving yield in the higher-priced crop, which in this case is soybeans. High-yielding wheat is not the focus. Instead, the crop is there to help the soybeans perform as well as possible.
“Wheat is my Dennis Rodman,” Mauck says. “If he was shutting down the best players, driving 20 boards and getting 7 offensive rebounds, that’s 7 more shots for Michael Jordan. There’s tons of value in that even though he didn’t score.
“We’re reducing the yield potential of that crop, but significantly increasing the yield potential and efficiency of the system.”
He understands that not growing high-yielding wheat may be a challenge for farmers, but if you flip the typical 80-bushel wheat and 40-bushel soybeans grown in a double-cropping system around, economically it makes more sense.
“If soybeans are $9 a bushel and wheat is $5, and you try for low wheat and low cost of goods and higher soybeans, just flip flopping the economics around is $160-$180,” he explains. “So you add the savings plus that, it’s a huge competitive advantage at $200 or $400 an acre.”
Mauck has found that this system allows him to plant his relay-cropped soybeans a month earlier than his monocropped soybeans, because the frost risk isn’t as relevant. “I’ve figured out that if I lay it about 10 inches away from the edge of the wheat, then it’ll grow in its ‘armpit’ and frost can’t kill it,” he says.
He adds that wheat is fine in cold, wet conditions typical in the spring, and will also consume excess water.
By planting the soybeans that early in between the wheat, it’s expediting canopy closure, as the soybeans push up over the wheat to reach sunlight.
Faster Canopy, Less Herbicide Use
Fast canopy closure is also key for Mauck’s second input savings — herbicide.
With wheat taking up 50% of the field, Mauck only has to apply herbicide to the other half. And since wheat helps with water infiltration, it creates a more even soybean crop throughout the field, which also helps reduce weeds.
“A lot of times in monocrops, it’s the thin crops that weeds win on that you’re just constantly fighting and pumping money into,” he says. “Those two crops together keep both of them more vigorous, which fights off weeds.”
Mauck’s herbicide program so far has been spraying one application of Xtend before wheat joint, which is usually in late March or early April. But since soil conditions aren’t always dry enough for his sprayer, next season he’ll be using a band-hood sprayer right behind the Dawn strip-till machine that he’ll use for soybean planting, so he can plant and spray at the same time. With that additional pass eliminated, he’ll save at least another $15 an acre.
Another improvement in the works is to do “twin and fill” on the soybean rows, where the middles are filled. This will expedite canopy closure even more, up to 4-5 weeks, Mauck estimates.
“That should be on farmers’ minds: how can we get to canopy quicker?” Mauck asks, adding that while the traditional thought is to go to narrower rows, by using two crops, it’s possible to achieve that fast closure in wider rows.
“What that allows you to do is spray your chemicals only on that space,” he says. “As we figure this out, we can start delegating jobs to nature so there’s no need to spray herbicide over the wheat. If you can get the canopy, then weeds aren’t a problem anymore.”
Between the residual herbicide application and the twin-row and fill, Mauck thinks he should be done completely managing his soybeans in April.
As for other pests, Mauck says has been able to avoid additional inputs.
“We get more airflow to dry the dew maybe an hour or two earlier every day, so that lowers your risk [of wheat disease] a little bit,” he explains, adding that fungicides and insecticides will slow the crop from drying down, which would negatively affect the soybeans.
Band Commercial Fertilizer
While Mauck doesn’t need to use commercial fertilizer, he says those using it can still adopt this system and reap the same benefits he’s experiencing, just by having roots in the ground year-round.
“It’s like the Rosetta stone for past fertilizer applications,” he says. “Just having living roots in the soil is going to make everything more plant available.”
To see additional input savings, Mauck recommends banding the fertilizer.
“If you can band it, you can essentially put the same row rate down, but omitting rows will exponentially cut costs,” he says. “You might put the same mix in with the seed drill of MAP and nitrogen, but you’re only planting 40% of the row. The initial plant gets that spark to multiply and you’re saving costs.”
The benefit of using this system in 60-inch rows is that because combines are set on 120 inches, Mauck can just drive down the wheat rows during harvest. This avoids having to invest in new equipment like skinny tires.
To harvest the wheat, he uses Flexxifingers, which extend past the reel to push the soybeans down, while still allowing the reel to push in the wheat heads.
In that 2019 Practical Farmers of Iowa Annual Conference presentation, Mauck shared a video of harvesting wheat in relay soybeans. The beans were a 4.8 maturity and about 2.5 feet tall. While the combine did take out some of the soybeans’ side leaves, the soybeans still yielded 106 bushels.
“Two years ago I had 108-bushel soybeans, the beans were about a foot taller than the wheat,” he recalls. “I was really worried at first, but we pulled it off. We’re compressing that bean down to about 6 inches off the ground.”
He adds that this is relatively easy to scale up, as another head can be put on in less than an hour. “I could conceivably call a dealership and have five combines out here with Flexxifingers on it and pull off a massive scale harvest,” he says.
There’s a lot of volunteer wheat afterward, which is another reason why it’s good not to get too aggressive in seeding and fertilizing the wheat.
“Having bigger, full-season beans will shade the light and not have as much volunteer wheat,” Mauck says. “If you have early maturing beans and they don’t fill in the rows, then you’ll have quite a bit of sunlight to empower any volunteer wheat and it will multiply and you’ll have a field of grass.”
By following Mauck’s suggestions in using a lower seeding rate and focusing on growing high-yielding soybeans, the volunteer wheat will instead serve as a nice cover crop.
What About Corn?
Mauck’s next cash crop after the relay soybeans is corn. He’s kept polycropping at a lower scale on his corn crop, but plans on doing everything in this system in a few years.
Right now he’s raising corn at 12-15% populations, and with soybeans, he says it might be just as profitable as monocropped corn.
“Corn has an incredible ability to recognize space. It’ll actually grow leaves on the ears and grow more ears on the same node,” he says, explaining that three years ago he grew a corn plant with 31 ears on it.
Corn could also replace wheat in growing high-yielding soybeans, as Mauck says he can plant one sixth of the corn and increase plant population by three or four times. He thinks it may be possible to band or eliminate nitrogen on corn and still grow an 80-bushel crop while increasing soybean yields with lower populations. If that’s true, “it’s going to blow the roof off the profitability of just growing beans or high-output corn,” he says.
Mauck’s plan for the future is to do twin-row corn on 60-inch spacings, and start cohabitating his own nutrition and weed control in between the rows with legumes for nitrogen production. Last year he did a plot in 20-, 40-inch rows and grew 300-bushel corn.
He also found that where rows were omitted in that plot compared to his normal monocropping corn, the corn there was always greener later.
“If you can just empower the lower leaves, you start to replace nitrogen inputs with sunlight,” he says. “We’re trying to drive top yields just by pumping late nitrogen to the corn. If we would widen the rows out and empower at least one side of the plant to grab a little bit more light, it’s more economical just from a nitrogen management standpoint. And we could grow something that would fix nitrogen out of the air between them too.”
Final Tips for Getting Started
Mauck always advises other farmers to start small with this system and remember the importance of wide rows with intercropping.
“No one ever listens to me on the solar corridor and wide rows, and then it usually turns it into a disaster, they just don’t have the sunlight or rainfall to drive the system,” he says.
He also recommends growers try several experiments throughout a field. “I learned a lot more by doing that than doing one thing,” he says. “You can expedite wisdom through more experiments.”
His system is always changing and evolving based on what he’s learned and continues to try. He wants to see other farmers get out of their comfort zones and learn how to capitalize on the variables they have.
“Eventually the finites are going to keep us from really increasing corn yields,” Mauck says. “I know the big companies say ‘feed the world,’ but eventually we only get so much water, so much sunlight and so many nutrients. If we want to empower ourselves, we have to figure out how to get more with less.”