Using 30-inch rows in strips could lead to higher yields, lower seed cost, less disease and a boost in profitability.

While most of the attention in strip-till gets paid to corn, there are some growers who are successfully strip-tilling soybeans.

Using 30-inch rows in strips could lead to higher yields, lower seed cost, less disease and a boost in profitability.

Veteran strip-tiller Jeff Reints of Shell Rock, Iowa, and more recent strip-tiller Bruce Wichmann of Fairfax, Minn., have each tried strip-tilling soy- beans in the spring and say they are pleased with yields and profitability. Both of them created large test plots comparing spring strip-tilled soybeans with no-tilled soybeans.

Reints has been strip-tilling for 10 years, and 2009 was the first year he strip-tilled soybeans. He typically no- till drills soybeans on 10-inch spacings. He says no-till works well on fields with light and variable soils and on the steep hillsides of his north-central Iowa fields.

But a combination of factors in 2009 led Reints to see how spring strip-tilled soybeans would work.

Planting soybeans rather than drilling enabled Reints to reduce seed populations from 190,000 seeds per acre in 10-inch, no-till-drilled soybeans to 150,000 per acre for strip-tilled soybeans in 30-inch rows. That saved $16 an acre.

Soybean diseases, especially white mold and sudden death syndrome, are becoming an increasing problem in drilled soybeans, so Reints felt the wider row widths would allow more air movement and reduce the likelihood of disease.

Pushing Soybean Yields

"Everybody is looking to try to get that little advantage in soybeans..."

- Jeff Reints

And, Reints keeps looking to push his soybean yields higher. While his overall corn yields have increased about 30% during the past 10 years from 160 bushels per acre to about 205 to 215 bushels per acre, his overall soybeans yields have only risen about 10% from 50 bushels per acre to 55 to 57 bushels per acre.

He wants more.

"Everybody is looking to try to get that little advantage in soybeans,"

Reints says. "We just are not getting that silver bullet to get soybean yields to the next level."

New varieties may do that, says Reints, a DeKalb and Asgrow dealer.

But instead of waiting for the silver bullet, Reints put in a large soybean test plot in a 120-acre field of strip-tilled soybeans. He dedicated 10 to 15 acres, comparing soybeans strip- tilled on 30-inch rows with those no-till drilled on 10-inch rows.

Overall, there were nine passes that he compared, with three strip-tilled passes getting an application of 12-23- 0-12s - a blend of DAP and AMS. (See Table 1.)

Fertilizer Boosts Yields

Reints added the fertilizer based on the recommendation of crop consultant John McGillicuddy, who said a low rate of fertilizer could help yields.

He did not use any potash because soybeans are very sensitive to it when they germinate.

The most profitable plots were four strip-tilled passes, three that had fertil- izer applied in the strip. Here's a sum- mary of the soybean experiment:

  • No-till drilled soybeans (10-inch spacings) averaged 53.8 bushels per acre and netted $462.33 per acre.

  • Strip-tilled 30-inch soybeans with no fertilizer averaged 55.7 bushels per acre and netted $474.82 per acre.

  • Strip-tilled 30-inch soybeans with 19-23-0-12S averaged 57.4 bushels per acre and netted $482.30.

Previously, that 120-acre field had been planted to continuous corn. Reints says he could strip-till the field because his Dawn Pluribus strip-till units handle residue without plugging.

While Reints has strip-tilled for 10 to 12 years, it's only been since 2008 that he's used a strip-till unit with coulters instead of shanks.

"We had no problem with residue going through the strip-till rig going at an angle to the old corn rows," says Reints, adding he usually makes strips in the center of the old corn row in continuous corn.

Planting conditions were about ideal, a marked contrast to the extremely wet spring of 2008.

"The corn stalks were dry and there was nice soil moisture," Reints says. "The year 2008 was extremely wet for northeast Iowa."

After 3 years of continuous corn, the field had "a fair amount of residue. It was 200-bushel-plus corn in 2008," Reints says. "We do a fair amount of corn on corn.

"At this point, I'll probably do some more 30-inch strip-tilled soybeans on flatter, heavier ground."

Reints says he still likes no-till drilling soybeans on steeper slopes, lighter ground and fields with a variety of soils.

"These fields, I'll continue to use the no-till drill. I'm not ready to give up on no-till drilled soybeans," he says, adding that he likes being able to no-till soybeans at the end of April while he's planting corn. "We'll keep using the no-till drill while the strip-till unit and corn planter are running."

Keys To Stripped Soybeans

Making strip-till work in the spring for soybeans requires several things, Reints says.

He likes the mixing of the soil that occurs with the Dawn Pluribus unit's 3-coulter system with firming wheels that firm up the berms.

"It really mixes the fertilizer," Reints says. "You get a real good blending of fertilizer within that whole zone."

Strip-tilling with a shank instead of a coulter runs the risk of creating a "hot zone," which can burn seedlings, he says.

And using shanks in the spring can lead to air pockets under the seed.

Looking back at his 2009 experiment with strip-tilled soybeans compared to no-till drilled, Reints says he wishes he had the time to include no-till planted beans, too.

"You have to have things dialed in just right," Reints says. "I love to learn. I love to keep experimenting, but there's a happy medium," he says.

Strip-Till Beans Win

In 2008, Wichmann decided to com- pare strip-till and no-till soybeans in an 80-acre field with half-mile-long rows. He chose two different Pioneer Hi-Bred soybean varieties, alternating eight rows of strip-till with eight rows of no-tilled soybeans. One was a 1.9 Y variety and the other a 1.8 Roundup Ready variety, Wichmann says.

Click to enlarge table

In all, each variety had 32 rows of strip-tilled soybeans and 32 of no-tilled beans. Planting dates were the same for all four test plots, which were side by side the entire length of the field

The strip-tilled 1.9s yielded 0.75 bushel more than the 1.9 that was no- tilled, Wichmann says. But the strip-

tilled 1.8 variety yielded 1.5 bushels per acre more than the no-tilled 1.8s.

By early July 2008, the strip-tilled soybeans had about 3 inches more vegetative growth and greater root mass than the no-tilled soybeans. At harvest, strip-tilled soybeans were 8 inches tall- er than the no-tilled beans.

However, the taller strip-tilled soybeans suffered lodging. Wichmann attributes that to the larger plant.

These strip-tilled soybeans netted $18 per acre more than the no-tilled soybeans, Wichmann says. He can strip-till 20 acres in an hour, using 0.4 gallons of diesel per acre.

A net profit of $18 per acre more for strip-tilled soybeans compared to no-tilled soybeans is significant for his small farm, Wichmann says. In 2009, he grew 245 acres of soybeans, 225 acres of corn and 75 acres of spring wheat.

"Residue management is the key to making strip-till work. The more residue you have, the more frustrations you can have making it work..."

- Bruce Wichmann

At January 2009 soybean prices and a rotation of 250 acres of corn and 250 acres of soybeans, Wichmann says his increased bottom line with strip-till is about $18,000 per year in fuel, fertilizer and corn drying savings.

That is compared to his previous mulch-till system of chopping stalks, V-ripping and two passes of spring tillage for soybeans; and one fall tillage pass and two spring tillage passes for corn. Now, he makes only one strip-till pass and saves two to three trips across the field.

Before strip-tilling, Wichmann used a broadcast application of 140-50-75 blend of incorporated fertilizer.

By banding with strip-till, he can reduce phosphorous and potash rates by 20%, and also saves a custom application charge. He sidedresses nitrogen by applying 120 units.

With no need to do fall tillage, Wichmann can let the corn crop dry naturally longer, giving him a savings of about 2% from a lower harvest moisture.

Manage Residue For Success

Wichmann is quick to say that strip-tilling in the spring isn't bullet proof. The biggest thing with strip-till is residue management.

"Residue management is the key to making strip-till work," Wichmann says. "The more residue you have, the more frustrations you can have making it work."

The combination of heavy, sticky soils with lots of clay and a limited amount of time to plant each spring lead to big challenges, he says.

Some of the land Wichmann farms once was considered unfarmable. Back in the1850s, land surveyors reported that Renville County, Minn., was so filled with marshes and swamps that it probably wouldn't be fit for farming, he says.

"We'll keep using the no-till drill while the strip-till unit and corn planter are running..."

Decades of tiling and making drainage ditches converted marshes and swamps into productive farmland, butthe challenges remain, says Wichmann. Being a one-man operation, he's turned to strip-till during the past 4 to 5 years to deal with a short planting window and heavy clay soils that don't warm up quickly. But he remains flexible, sometimes no-tilling soybeans into corn or corn into soybeans.

It's not uncommon to have frost in the ground on March 20 or later, Wichmann says. Less than 3 weeks later - April 11 - is the first date for crop insurance coverage for corn planting, he notes.

The optimum time to plant corn in his area is April 20 to 25, says Wichmann. Corn planted after April 25 begins losing its maximum potential yield, he says.

Wichmann says strip-till helps him get the quick warm-up of the black soil typical with conventional tillage, while conserving moisture and protecting the soil with residue similar to no-till. However, he says increasing levels of residue can be a problem.

After 3 years of strip-tilling, Wichmann was planting into heavy "residue windrows" that were 10 to 12 inches thick between the rows.

He says residue accumulates not only because Bt corn stalks don't break down as quickly as conventional hybrids, but also because they don't break down much in the fall. Before winter officially arrives in December, snow often covers fields, he says.

He estimates that, at best, there are only 5 weeks for residue to break down before the ground freezes and snow and ice set in. And there's little time in the spring, too, for residue to deteriorate before planting needs to begin.

Rolling Breaks Corn Stalks

Rolling corn stalks can help, Wichmann says. In 2009, after no-tilling soybeans into standing corn stalks, he rolled the field to break down the stalks.

He used a 45-foot-wide Degelman roller, which has a 3-foot-diameter drum made of a 0.5-inch-thick steel plate. The roller levels the ground, pushes rocks down into the soil and smashes and splits corn stalks.

This gets residue in contact with the ground and helps the center of stalks deteriorate more quickly, he says.