Using Residue Layers, Precision Tools to Boost No-Till Profitability

Variable-rate seeding and fertilizer application, and keeping fields covered, is enhancing South Dakota grower Todd Yackley’s successes with no-tilling.

Without the use of precision ag tools, Todd Yackley believes he’d be far less successful no-tilling 40,000 acres near Gettysburg in central South Dakota.

A fourth generation farmer, Yackley works with his father, Bob, his sons Blake and Wayne and son-in-law Brandon Bertsche. The family raises spring wheat, winter wheat, corn, sunflowers and occasionally soybeans.

Of the 40,000 acres, approximately 10,000 acres is planted to each of Yackley’s four main crops. Fallow is no longer part of their crop rotation plan.

No-Till First

In the early years of the farm, one third of the acres were fallowed, so the soil was bare until winter wheat was planted in September. The next year, wheat stubble was tilled and then planted to corn.

“Neither the rotation nor the tillage were good,” Yackley says. “But 30 or 40 years ago, that’s what everyone did.”

Growing up raising wheat, fallow and some corn with a scant 15-18 inches of annual moisture, Yackley was well acquainted with the need to preserve moisture when he took over the family farm in the 1980s.

At the time, conventional tillage was common in his area. That began changing when Dwayne Beck implemented no-till practices at the nearby Dakota Lakes Research Farm.

“There were some growing pains during our transition to no-till,” Yackley says. “We pursued no-till because we could see the success some neighbours had and we could see our soil improving, and also our yields.”

One of the first results Yackley noticed after implementing no-till was significant improvement of soil moisture retention, with between 40% and 50% more moisture infiltrating the soil. Leaving residue in the field helped catch snow, providing a moisture boost in spring.

Throughout the growing season, leftover crop residue helped keep soil temperatures down and reduce evapotranspiration, he says. After 8 or 9 years of no-tilling, increased soil tilth and soil organic matter as well as improved water infiltration were obvious. In the tillage days, soil organic matter averaged about 2.5%, but it has risen to 4%-4.5%.

High-Yielding Corn

“Our most successful practice with no-till has been corn planted into winter wheat stubble,” Yackley says. “We leave as much wheat stubble in the field as possible to help preserve moisture into late July and early August, because in central South Dakota we can get extremely hot and dry in those months.

“Keeping just an extra inch of water in the soil has helped boost our corn yields as high as 130 bushels an acre in poorer soil zones, 160 bushels in medium zones and up to 180 bushels in our good zones.”

In the days of conventional tillage, corn yields in Yackley’s area averaged 70-90 bushels per acre. In part due to growth in no-till practices, Sully County corn yield averages have increased to 120-170 bushels per acre.

“We use stripper headers to harvest our wheat, which leaves our stubble at least 2 feet tall in the field,” he says.

Annual Targets

Aside from simply no-tilling and leaving more residue in fields, the Yackleys say adopting more precision technology in the last 5 years has helped make their farm operation even more profitable.

They’ve implanted variable-rate planting and fertilizing that allows them to maximize results in their best soil zones, and plant and fertilize poorer zones to obtain the best possible yields with the least possible inputs.

Soils in many of their fields are consistent. But many fields have areas where topsoil is shallower, has lower organic matter and less water-holding capacity, causing growing conditions within a field to vary greatly.

The Yackleys work with their agronomist, Rick Weber, to develop each year’s crop plans. Weber soil samples every field by zones every year.

By identifying these areas and reviewing current soil nutrient conditions, projected crop needs by zone and field history, Weber develops variable-rate prescriptions for seed and fertilizer.

Through a combination of satellite imagery, the growing history of each field and soil test results, Yackley’s agronomist calculates what nutrients are in the soil and what nutrients are needed to grow the next crop.

Planting on 30-inch rows with two 36-row DB90 John Deere corn planters, Yackley uses Precision Planting’s VSet meters. A Deere DB60 24-row planter is set up for the dual hybrid fields. A Precision Planting 20/20 SeedSense monitor adjusts to prevent headland overlap, which saves seed and can boost yields in those areas.

“In our fields, corn plant populations range from 20,000 seeds an acre in poor zones to between 30,000 and 32,000 in our best zones,” Yackley says. “We also use dual-hybrid planting to put racehorse hybrids in the best zones and hybrids that are more defensive in the poorer zones.”

Yackley relies on the input of his seed representatives, as well as plot tests in his area to select the best possible hybrids for each field. DeKalb varieties have worked well for him for the past 15 years. He’s experimented in small plots with new hybrid numbers to stay on the cutting edge of hybrid seed advantages.

Precision Profitability

Part of Yackley’s precision approach to farming includes detailed equipment maintenance during winter to make sure everything is operating correctly and any necessary repairs are completed.

“We pride ourselves on having the best crop stands around,” Yackley says. “You only have one shot at putting your crop in the ground, so it’s critical to pay attention to detail and do the best possible job of planting.

“We want our corn plants to emerge within 24-36 hours of each other so the crop stays uniform through harvest time. Keeping an even emergence is a science, but that’s our job. We like to do it and we work hard at it.”

Even emergence of corn plants prevents emerged plants from responding to late emergence as if the late corn plant was a weed. To help avoid this, Yackley uses Precision Planting’s CleanSweep system, which lets him control the depth row cleaners are running at from the cab, to adjust to field conditions on the go.

His planters are also equipped with Precision Planting’s DeltaForce system that automatically adjusts down pressure on row units so seed is placed at a uniform depth.

With the assistance of auto-steer to maintain precise rows, consistent seed placement means all the corn plants can receive equal sunlight and heat as they grow, Yackley says.

Yackley adds he’s been pleased with the job the Thompson closing wheels have done the last 8 years in breaking seedbed sidewalls and covering seed corn.

Strategic Fertility

Most of Yackley’s fertilizer is applied in October, after summer’s daily temperatures have started declining. Because of low average moisture in the area, leaching and volatilization isn’t usually an issue.

He uses a John Deere 2510 high-speed applicator with an anhydrous single-blade application bar to apply nitrogen, at a rate of up to 45 acres an hour.

A John Deere 1910 500-bushel air cart, pulled along with the 2510, applies dry phosphorus and potash. At planting, 4-5 gallons of pop-up phosphorus is applied in the row with planters.

“That fertilizing process has been very efficient for us,” Yackley says. “The strip bar is low disturbance and we’re able to get through heavy fall residue to apply our fertilizer. Using RTK, we plant right on the path of the strip bar in spring.”

Adjusting to Residue

Most years, Yackley doesn’t encounter wet planting conditions. A very good 2014 winter wheat crop left large amounts of standing stubble.

Even though the fall, winter, and spring leading up to the 2015 planting season were very dry, Yackley had good topsoil moisture to get the crop off to a good start. Yackley experienced some issues planting through the super thick residue, but waiting out the weather for drier conditions and sunny, low humid days proved to be a successful planting strategy.

In planting sunflowers with his JD planter and wheat with a John Deere 1895 air seeder, Yackley is careful to select sunny, low humid weather conditions to reduce potential for residue bunching or hair pinning.

Because residue is key to maintaining soil moisture that’s so critical for the corn crop in July, he didn’t worry about the extra effort needed to complete corn planting.

“In fall, we aren’t able to harvest on cloudy, gloomy days either,” Yackley says. “Having the patience to wait for the right planting and harvest conditions is our best strategy.”