Use A 'Systems Approach' To Boost
Spreading residue, staying ahead of weeds and striving for uniform growthcan help no-tillers get more out of every acre.
Use A 'Systems Approach' To Boost
One tip often shared by yield-contest winners is keeping no-till field conditions uniform, with even plant growth and competition for moisture and nutrients, says University of Nebraska Extension engineer Paul Jasa.
More no-tillers could boost yields if they adopted a similar “systems approach” as they think how each farm-management decision affects the next. Jasa shared some basic tenets of this approach during the 2011 National No-Tillage Conference in Cincinnati, Ohio.
Match Up Equipment
Growers must decide whether their equipment lineup is compatible with their goal of successful no-tilling. Jasa discussed a field where cornstalks were leaning in two directions, created by a no-tiller with a six-row combine and a 12-row planter.
Get with the system. One key to adopting a systems approach in no-till is making equipment decisions that allow high levels of efficiency, says University of Nebraska Extension engineer Paul Jasa. "If a no-tiller is using one 120-foot planter, what does the field crew do while the planter is in the field for a few hours? Maybe two 60-foot planters will help you and your tender crew get more done."
“So half the planter works great, but with the other half, every hose, wire, cable and chain is catching residue and you’re complaining about no-till,” Jasa says. “That’s not a no-till problem, that’s a harvest problem. You’ve got a planter twice as wide as your combine.
“If you harvest two passes the same direction, and two passes back in the same direction, then plant the direction the stalks are leaning, that problem goes away. Think how things all fit together.”
No-tillers shooting for a one-pass system must also make careful equipment decisions. If a no-tiller is using one 120-foot planter, what does the field crew do while the planter is in the field for a few hours planting?
“Maybe two 60-foot planters will help you and your tender crew get more done,” Jasa suggested. “If you have a breakdown with the 120-foot-wide planter, you have no movement in the field. With two 60-foot planters, you may have one break down but the other planter is still moving.”
Jasa mentioned a no-tiller who wanted to plant narrow-row beans, but said he couldn’t justify using a large air seeder for so few acres. But he found another purpose for it.
“His air seeder is now his fertilizer bar for all his corn acres, and he does custom work in the fall after harvest if he has time,” Jasa says. “When you’re talking about a systems approach, think about other uses for the same piece of equipment.”
Plant Down The Old Rows
"By planting deeper, I might delay emergence slightly, but I'll get a more uniform emergence and better yields..."
— Paul Jasa, University of Nebraska Extension engineer
Jasa says planting in the old rows is important to maintaining the soil’s structure and creating uniform growing conditions.
“As I plant down the old row, the residue is standing prior to planting and I get air movement down to the soil,” Jasa says. “I wouldn’t plant in wheel tracks, especially with some of the tractors we have today. You get some pretty heavy wheel tracks.”
“I would use controlled traffic as well so you’re not breaking down the rest of the soil system.”
Keep Summer Soils Cold And Wet
One complaint Jasa hears about no-till is that residue will keep the soil cold and wet in the spring, possibly delaying emergence.
One year, he decided to investigate this. He planted corn in mid-April on a first-year no-till field, then went to a lumber yard and bought R19 insulation that was 6 inches thick. He placed it in the field and pinned it to the ground with flags. Then he watched the results.
“Yes, the soil was cold and wet, and there was slower early-season growth,” Jasa says. “But when I looked at uniformity, one plant looked a lot like the next plant, and the next.”
Citing the teachings of no-till researcher Dwayne Beck, Jasa adds that no-tillers shouldn’t focus on making spring soils warmer and drier, but rather making the summer soils cooler and wetter. This may be especially important in climates with limited moisture, where pushing away residue at planting time may warm up and dry out the soil and leave it exposed all growing season.
He mentioned a recent year when a University of Nebraska research plot of grain sorghum was punished by five straight days of 100 F temperatures. Once rain returned and brought the plants out of dormancy, the no-tilled plots of sorghum yielded 35 more bushels per acre.
“Where I had residue, the soil was cooler and wetter, and the plants kept growing,” he says. “Residue is our friend when it comes to conserving water. If you’re that person who always needs that one extra rain, the residue will help keep the moisture there.”
Plant Corn Deeper
Jasa suggests no-tillers plant corn 3 inches deep to take advantage of the improved soil structure and buffered soil temperatures and moisture created by continuous no-till. A Nebraska producer he worked with had for years been planting irrigated corn at 2¼ inches, but agreed to do some plots at a 3-inch depth.
His yields increased that year from 199 bushels per acre to 217 bushels and the uniformity of growth was improved.
“Everyone says, ‘Wait a minute, isn’t it colder deeper?’ It might be, but what I found is when I plant deeper, I get a more buffered soil temperature and soil moisture,” Jasa says. “Planting shallower might make a plant emerge a lot faster. But I don’t want one plant emerging one day and its neighbor 10 days later.
“I want plants emerging within a day or two of each other. By planting deeper, I might delay emergence slightly, but I’ll get a more uniform emergence and better yields.”
Keep Weeds Under Control
Jasa says it’s crucial to stay ahead of weeds before they get too large and sap moisture from the soil. Some herbicides that are effective in climates with abundant moisture may not work as well on dryland farms, where there often isn’t enough moisture to incorporate the chemicals.
Jasa suggests a pre-emergence herbicide applied early, with a post-emergence application as necessary.
“As you look at your herbicide labels, most show a rate for a 2-inch or 4-inch tall weed. There’s very few that talk about 2- and 4-foot tall weeds,” he says.
He adds that flat-fan nozzles are superior to flood-jet models for herbicide application.
The right rotation. Having a wide crop rotation — such as this no-tiller in the Palouse region in the northwestern U.S. who’s growing wheat, lentils, peas and garbonzo beans — can help growers build a one-pass system, says University of Nebraska Extension engineer Paul Jasa.
“I like 100% overlap on spray nozzles. That way everything gets sprayed from two sides,” he says. “If you get a sagging boom, you still get coverage. If you get a partially plugged nozzle, you still get coverage. If you find a partially plugged nozzle, that’s already a 50% error in application.
“Know your weeds, know your labels and know what your weed-control program is as part of that systems approach.”
Distribute Crop Residue
Just like other aspects of no-till systems that need fine-tuning, managing the depth and density of residue in fields is key, Jasa says.
Evenly distributed residue ensures every seed is under the same soil moisture and temperature, aiding in even emergence. Windrows or piles of residue not only hurt emergence, but get stuck in openers, or plug up a drill or fertilizer bar.
“What I want to do is spread that residue and chaff out so I hold moisture across the entire soil surface. Spread the residue out and get it working for you,” he says.
Residue should be managed from the combine, Jasa adds. Older combines with narrow heads cause fewer problems, but the wider heads used today may require additional planning by no-tillers.
Stripper headers or improved snapping rolls on the combine might be worth considering because they can process the residue at harvest.
Jasa showed no-tillers at the conference a picture of a large Caterpillar combine outfitted with knife snapping rolls that a longtime no-tiller used that year to harvest cornfields with 20-inch rows. He averaged 265 bushels per acre.
The grower needed the residue for erosion control on his hilly fields. Despite 18 rows of corn being run through the combine, the amount of residue coming out the back wasn’t overwhelming.
“That’s because the corn head with that knife design was processing the residue. Get it processed,” Jasa says.
Be Wary Of Residue Movers
Jasa says he doesn’t favor the use of residue movers, fluffing harrows, or vertical tillage — especially in windy regions like the High Plains where residue can be blown around.
He remembers getting a call from a long-term no-tiller who used a “coulter-tillage machine” in the fall to cut up cornstalks and get them in contact with soil microbes to aid their decomposition.
By March, piles of residue up to a foot deep were left in the field.
“So now we definitely had non-uniform seeding conditions there because he did that extra step,” Jasa says. “I’m not a fan of those types of machines because it cuts things loose. Doing this a day before planting may not be a problem. Do it the fall before and there may be a problem.”
Use Cover Crops
The soil biological activity provided by cover crops can process residue, fix nitrogen in the soil and be an important part of a no-till systems approach, Jasa says.
He noted the results of Austrian winter peas planted after corn harvest on the university’s plots, and the manageable levels of residue found the following March, along with nitrogen released from the decaying covers into the soil.
On another research plot with 4 years of corn-on-corn and 3 years of cereal rye cover crop, Jasa again noted increased soil biological activity and faster cycling of residue.