For more than 25 years, Brandon Hunnicutt’s family has utilized some form of conservation tillage. He farms about 2,600 acres with his dad, Daryl, and brother, Zach, near Giltner in south-central Nebraska.
But it wasn’t until 2006 that they committed to strip-till on the majority of their acres after primarily no-tilling and ridge-tilling corn, soybeans, seed-corn and popcorn. Hunnicutt moved from 10-row mounted planters for ridge-till to 24-row, pull-type planters and found that keeping the implement on the ridge proved to be a challenge.
“Strip-till looked like it was going to be that nice marriage of those different tillage strategies, and it has been,” Brandon says.
Patience is a big part of Hunnicutt’s strip-till philosophy. He prefers to build strips in the fall, but doesn’t apply nutrients until spring. This guards against wasting fertilizer and also provides flexibility when deciding which crops to plant.
The Hunnicutts strip-till about 2,200 acres, and the last few years have been a split of 75% corn and 25% soybeans, with a few seed-corn and popcorn acres.
“Our goal has been to get the strips made, have everything grid sampled in the fall, have the co-op put on any variable-rate fertilizer in the spring, then come back and add a little phosphorus and Thio-Sul with one of the liquid applications,” Brandon says. “If we have everything strip-tilled, that leaves it wide open.
“If, for some reason, we had a field that was going to be soybeans and the corn market suddenly takes off, we’re ready to switch the crop rotation and go right into corn.”
The Hunnicutts use a 12-row Orthman 1tRIPr to build strips about 10 to 12 inches wide and 6 to 8 inches deep. In the spring, for corn, they apply 5 gallons of 9-24-3 with the planter and use a mixture of 32% nitrogen, 10-34-0 and Thio-Sul post-emerge.
The strategy is working well for the Hunnicutts, who irrigate all of their corn and are seeing yields of 240 to 260 bushels per acre. They also are getting a bump in soybean yields.
“If we see, consistently, a 1-to-2-bushel increase per acre for soybeans, it pays for the application being out there,” Brandon says. “If we’re strip-tilling, we’re keeping everything consistent. Last year, we noticed that we got to the point of hitting that magical zone where everything was strip-tilling really nice.”
Brandon is considering application of nutrients in the fall strips, but one challenge is making sure fields are grid sampled right after harvest so the proper amount of nutrients are placed.
Another obstacle is the potential of fall fertilizer application in the Hunnicutt’s area being limited by regulators. With parts of Nebraska already regulating nitrogen application — farmers in some areas of the state have to wait until March 1 — any ambition to incorporate fall nutrients could be a moot point.
“I’ve got a feeling things are going to continue going that way in the state, so we might be better off pushing our spring fertility program in other ways,” Brandon says.
Sensing Nutrient Needs
One tool the Hunnicutts use to be more precise with application of spring fertilizer is crop sensors to detect the right time to apply in-crop nitrogen. They've worked with the University of Nebraska, the USDA Agricultural Research Service and a seed company to do the sensing, and have been able to reduce spring application amounts.
“We’ve done this for a number of years, but last year was the first time we had some interesting results. After applying 32% at V10, we averaged about 10 gallons per acre at that point,” Brandon says. “In the areas where we used the sensors, our application was about 25 gallons less per acre than past years, but we didn’t have any yield loss.”
This year, the Hunnicutts added three Ag Leader OptRx crop sensors to their John Deere 4830 self-propelled sprayer to experiment with their own sensing. They’re hoping to be even more precise with nutrient application, based on the sensor readings.
“What we learned last year is if we would have used crop sensors on all our acres, gallon-wise, we would have saved 40,000 gallons of 32% fertilizer,” Brandon says, “This year might be completely different and we might need to put on an extra 40,000 gallons, but it gives us another tool to not only apply the right amount of nitrogen, but, at some point, spoon feed some extra nutrients to the crop.”
Another recent modification in the Hunnicutt’s strip-till operation is how they build strips for corn after soybeans. Typically, they would move the rows over 15 inches to avoid the residue, but have also tried moving 4 inches off the old row.
The results were mixed and Brandon says they struggled with being able to maintain the row. So last fall, they built strips right over the old rows.
“In the fields that we are going to corn from old soybean ground, we’re strip-tilling basically right over that old row, instead of moving over 15 inches,” Brandon says. “It saves the tires because they do get eaten up quite a bit if we have to run over the old stalks.
“If we go right back into the old row, we should have a nice root zone established already. We just go down and open up the top 8 inches and we should have a nice penetration for the corn rows.”