Farming in Weston, Neb., in the eastern part of the state, Ron Kadavy is accustomed to dealing with high winds, low humidity and inconsistent rainfall on his 2,000-acre corn and soybean operation.
This combination of challenges often limited his no-till corn yields because plants struggled to consistently emerge in dried-out heavy clay soils, or receive adequate nutrients throughout the growing season.
“No-till corn was a real bear for us, because some years we’d have parts of the field where the wind blew residue into piles and other areas would be completely clear,” Kadavy says. “Broadcasting phosphorus over the top, most of it would just lay there because we didn’t have enough earthworm activity to move it. If we did get a big rain, most of it would end up in the waterways.”
Seeking more yield consistency and better nutrient management, Kadavy began strip-tilling corn into no-tilled soybeans a decade ago. He began by experimenting with organic fertilizers and deep-placed liquid applications with a 12-row Strip Cat coulter rig made by Twin Diamond Industries.
With strip-till, his corn yields have reached 240 bushels per acre on irrigated acres and about 185 bushels per acre for dryland corn — both well above his no-till averages.
“We’re seeing a good 20-bushel-per-acre boost over no-till, depending on the spring,” Kadavy says. “If it’s warm all the time, no-till can work. But 8 out of 10 years that’s not the case, and strip-till has proven to be a real improvement for us.”
One of the things Kadavy learned through trial and error was how to be more efficient with fertilizer placement to ensure crops could access nutrients when they’re needed.
PRECISION MANAGEMENT. Technology allows Kadavy to accomplish more in a day and a recent upgrade to RTK with John Deere’s StarFire 2 receiver lets him more accurately manage inputs by avoiding overlap during planting and spraying.
He used to broadcast monoammonium phosphate (11-52-0) in the fall onto soybean stubble and build strips in spring. The hope was that the fall application would provide a nutrient jumpstart ahead of spring fertilizer applications with the strip-till rig and planter.
“I never saw enough of a yield boost to justify the cost of having it spread, because it was just too shallow of an application,” Kadavy says. “It would lay on top and the little I strip-tilled in never got to the plant.”
Kadavy moved to deep-placing nearly 100% of his fertilizer with the strip-till rig in spring, about 8 inches below the soil surface. He applies 140 pounds per acre of liquid 32% actual nitrogen and 8 gallons per acre of ammonium phosphate (10-34-0) on 800 acres total of dryland and irrigated strip-till corn. He also applies about 4 gallons per acre of sulfur, with smaller amounts of zinc and boron through a 3/8-inch-thick fertilizer knife.
“I thought the half-inch knife would be too aggressive, so I wanted a skinnier knife,” Kadavy says. “I move very little soil because I don’t want to create channels.”
The row units also feature covering disks followed by two rubber firming wheels mounted on a bracket. These run at a slight angle and help finish the 10-inch-wide strip.
“They help pack the soil down just enough to seal the strip and conserve moisture,” he says. “Putting that much fertility in a row underneath a corn plant, I want extra dirt in between, because if I left it fluffed up I’d have 4 or 5 inches of dry dirt.”
With his 12-row John Deere 1710 planter, Kadavy applies 4 gallons per acre of a starter fertilizer package (9-24-3) that includes zinc, copper and manganese.
GROUND CONTROL. Weston, Neb., spring strip-tiller Ron Kadavy moved to deep-placing nearly 100% of his fertilizer with 12-row Strip Cat strip-till rig about 8 inches below the soil surface to ensure corn plants access nutrients when needed during the growing season.
“I have fertility on the top, right from the start for the plant,” he says. “As the growing season progresses, the roots take hold and there is another batch of fertility, hopefully where there is a lot more moisture left. That second batch of fertility can really pull plants through a dry spell.”
Last year, a wet spring prevented Kadavy from strip-tilling one field, so he took the opportunity to do a fertility comparison vs. no-till. He deep-placed fertilizer on strip-tilled fields and applied half his nitrogen and sulfur with the planter, and sidedressed the balance on the no-till field.
“The no-till farm yielded about 30 bushels per acre less than my strip-tilled fields,” Kadavy says. “It never rained enough after that wet spring to get that fertility to the plants. In the future, I’ll spend that one more day in the field strip-tilling because it will pay off.”
In addition to using fertilizer more efficiently, Kadavy is conscious about improving soil health — especially on recently acquired farms, some of which having been conventionally tilled for years.
SEALING THE STRIP. The row units on Kadavy’s Strip Cat rig feature covering disks followed by two rubber firming wheels mounted on a bracket. These run at a slight angle and help finish the 10-inch wide strip and pack the soil down just enough to conserve moisture.
He’s experimented with applying small amounts of liquid organic fertilizers, including fish, kelp and molasses with the planter, to improve soil structure and increase earthworm populations.
Kadavy says he got the idea to incorporate organic fertilizers from reading articles on success organic growers were having improving yields.
“If those farmers can raise some decent crops without using commercial fertilizer, I think it can be worthwhile for us,” he says. “We’ve seen some benefits in our operation, with residue breaking down faster due to more microbial life in the soil, and organic matter improving to 3.5% or 4% in some fields.”
He recently did a side-by-side earthworm population test in a strip-tilled field, placing two wooden planks between rows. Under one plank, Kadavy placed a small amount of molasses, and then put nothing under the other one.
Two months later, he checked under each plank and found that both the population and size of earthworms under the molasses plank were larger than under the bare plank.
“This was a farm that had been pretty heavily tilled by the previous owner and I couldn’t hardly find an earthworm when I bought it,” Kadavy says. “Now, there’s quite a few. I attribute that to feeding the soil and also with strip-till, we’re not destroying that structure.
“I’ve noticed on some of my hills that once I get a good earthworm population established, the ground just absorbs water so much faster and better.”
Cedar Bluffs, Neb., strip-tiller Ron Kadavy discusses the benefits of strip-till and deep placement of fertilizer to control erosion on his sloping hills, and how the practice has helped boost both corn and soybean yields.
Last year, Kadavy upgraded his precision farming arsenal to include a move to RTK guidance for building strips and planting. He purchased a John Deere 2600 display and StarFire 2 receiver to mount on the top of his Deere 8310 tractor.
“I’ve used GPS for years, but was hesitant to move to RTK because I would have had to pull a signal from a tower 17 miles away,” he says. “Now there’s a tower 5 miles away and I don’t have to worry about the signal dropping out at the base of a hilly area.”
One of the biggest benefits with RTK and swath control, Kadavy says, is being able to better manage inputs. In the past, he wasn’t as consistent staying on the strip that resulted in either a shortage or excess of fertilizer or chemicals at the end of the season.
“It’s usually pretty close now because I’m not overlapping,” he says. “It’s hard to put a pencil to the cost savings, but it’s been worth it.”