Increasing Profitability While Building Soil Health

Husband-and-wife team Dan and Kris Nigg have increased the profitability of their corn-and-soybean operation by reducing tillage, growing cover crops, and putting variable-rate technology to work. 

Successful Farming spoke with Dan Nigg, who was named a Soil Health Champion by the National Association of Conservation Districts, about how the three-point formula has led to better crop yields.

“While yields are growing, costs are decreasing,” said Nigg, who farms in northeast South Dakota. “When you take away a lot of the expense while increasing yields at the same time, the return to the bottom line is going to be a lot better.”

Reduced Tillage, Plus Equipment Savings 

The Niggs transitioned to reduced tillage around 20 years ago by primarily practicing no-till, except for the vertical-tillage pass they make ahead of planting soybeans into cornstalks. Switching to conservation tillage had the immediate effect of reducing machinery costs.

“Cutting back on tillage let me eliminate a lot of equipment,” Nigg said. “When we still practiced conventional tillage, I had a chisel plow, a ripper, and a field cultivator. We got rid of $300,000 to $400,000 worth of equipment, and we don’t have to worry about replacing it.”

Fewer passes across fields have meant fewer operating hours for a tractor. “We used to put 500 hours on the tillage tractor every year,” Nigg said. “Last year, we ran the same tractor for just 180 hours. Eliminating about 300 operating hours on a tractor means we don’t have to trade that tractor as often. That’s a big savings when you’re looking at a replacement cost of at least $700,000.

“Overall, we’re reducing costs for machinery maintenance and replacement, as well as reducing costs for fuel and labor,” he said. “The total cost savings amounts to about $60 to $80 per acre per year.”

The Niggs have also reduced machinery costs by sharing ownership of equipment with another farmer. Together, the partners own two 60-foot planters and a sprayer. “We’re able to run less machinery on more acres,” Nigg said.

While downsizing their line of equipment, the partners incurred an additional cost of upgrading planters by adding a hydraulic downforce system and a furrow-closing system. These systems improve accuracy in seed placement and achieve better seed-to-soil contact.

Utilizing Variable-Rate Technology

To reduce fertilizer costs, the Niggs grid-sample fields and apply fertilizers using variable-rate technology. “We just spread P and K, for instance, where the grid sampling shows that it’s needed,” Nigg said. “That saves on fertilization costs.”

Nigg said he uses the same technology to adjust plant populations according to soil type. Because the grid sampling reveals differences in soil types, Nigg can use this information to “prescription plant” corn.

“When I’m planting into sandier soils, the corn planter reduces the population of seeds,” he said. “In heavier soils, I plant corn at a rate of 32,000 seeds per acre. On sandy soils, I reduce the rate to 24,000 seeds per acre. That gives the plants more space, and they don’t ‘burn up’ as much during dry growing conditions. The reducing seeding rate saves on seed costs.”

Cover Crops Improve Soil Health

As overall costs have decreased, yields have continued to climb, in large part due to improved soil health. Introducing cover crops combined with reducing tillage has resulted in soil organic matter climbing to around 5%. “I’ve taken on new land that tested only 2%–3% in organic matter and it’s climbed to 4% in 10 years,” Nigg said. “But some soils are light, and it’s hard to build organic matter on those soils.”

The Niggs said they have also noted increased biological activity in the soil, and improvements in soil structure. One practical outcome is the improved maneuverability of heavy equipment. “When we drive into a field in the spring, the equipment doesn’t sink into wet soil,” he said. “The soil structure holds machinery up better.”

To help heavy equipment better navigate wet soil, the Niggs have refitted their machines with low-sidewall tires. The tires’ design helps prevent equipment from sinking into muddy spots, Nigg said.

When the Niggs began growing cover crops in 2010, they started with cereal rye. It remains their cover crop of choice for cornfields where they will plant soybeans the following spring. After harvesting the corn in October, they broadcast the rye seed with a 60-foot airflow spreader. While the cold fall weather prevents the rye from getting a good start in fall, it grows well the following spring, Nigg said.

The Niggs’ rotation also includes a small amount of spring wheat. After harvesting wheat in midsummer, they plant a multispecies cover crop mix of turnips, radishes, flax, and field peas. All the species winter kill, eliminating the cost of terminating the cover crop in spring. They plant corn or soybeans into the residue.

For the Niggs, the combination of controlling costs while building healthy soil has led to a more resilient, financially stable farming operation. “The bad years are a lot easier to take,” Nigg said.