OMAHA (DTN) -- I have a problem with excessive corn residue in a continuous corn rotation. The residue complicates my no-till planting strategy and results in less-than-ideal plant stands. I have listened to planter experts and added many gizmos to my planter to handle the residue.

Still, no-till continuous corn hasn't worked out.

I can easily no-till corn into soybean stubble, but that's not much of a challenge. Soybeans also aren't as economically viable in our operation as corn. I don't want to do full tillage. Strip-till isn't a good option in my area: Fall strips create erosion in our hills; spring strips dry out the soil.

The best option is to process residue and the seedbed surface in advance of planting, while leaving crop residue on the surface. Cutting and sizing residue allows my planter to do its job in high-residue situations.

THE VERTICAL TILLAGE OPTION

Vertical tillage, a relatively new trend, appears a good option. Many equipment manufacturers have designed vertical tillage tools. I have tested several of them.

Before you buy one of these new units, decide what your objective is and try out the tool in the configuration that meets that need before buying. While I found that vertical tillage tools typically do the job they were designed to do, they are not all the same.

DeAnn Presley, soil specialist at Kansas State University, said, "The main objective of using vertical tillage is to break up surface soil compaction, or smooth out areas in a field with shallow (2- to 3-inch) rills from water erosion or ruts and tire tracks from tractors, combines, grain carts, trucks and other equipment. It also is used to help improve rainfall penetration by breaking up crusts."

Presley said these tools lightly till the soil. They cut up residue, mix and anchor some of the residue with soil, but still leave large amounts of residue on the surface to protect the soil from erosion. "This action helps speed residue decomposition," Presley said.

Another relatively new form of vertical tillage is done with aeration tools, designed to fracture the soil and improve aeration, but are not as good to process residue and prepare the seedbed.

SETUP AND OPERATION

Vertical tillage tools differ in both setup and operation. It's important to listen to the salesperson explain the role played by each component of that tool.

Most tools run at a depth of 2 inches, so there's no need to run them deeper.

Speed, however, is critical. Each of these tools operates at specific speeds; if the company recommends 8 mph, you need the horsepower to pull it at 8 mph in different terrain and soil conditions.

Many vertical tillage tools are built with coulters up front that cut and size residue and do light tillage. The rigs may have one or several gangs of coulters. The coulters may be followed by a rolling or straight harrow that mixes some soil with the residue, while tilling the seedbed. Some tools include a rolling basket that crushes clods while leveling the seedbed.

Aeration tools differ in that, instead of coulters, harrows and a rolling basket, they're equipped with shattertines -- three-lobed tines that are indexed to enter the soil in a sequence as the axle turns. These tines fracture the soil as they roll and leave a divot as they exit. A trailing rolling harrow fills the divot and levels the soil.

Aeration tools typically run 8 inches deep at a speed of 6 mph; they require more horsepower per foot of tool width than a vertical tillage tool.

SET A GOAL

To choose the right tool, decide its purpose. Do you want to process residue, blacken the soil and prepare a seedbed? Do you want to process residue, lightly stir the soil surface and prepare a seedbed? Or do you want to loosen and aerate the soil, while partially processing residue and leveling the field?

I wanted to cut and size residue, fluff up and prepare the seedbed surface, yet leave more than 80 percent of the residue on top of the soil. After testing an aeration machine, I need to rethink that goal. Compaction is probably my number one problem.

DECIDE ON A MACHINE

Conventional vertical tillage tools are built by Case IH, Great Plains, Landoll, Salford, Summers and other brands. While they are all vertical tillage tools, they aren't built the same. Be aware of the design differences and how that affects their action in the field. Get out in the field and look closely at their differences on residue and seedbed.

Last spring, I had a Case 330 Turbo, Great Plains Turbo-Till and Turbo-Chopper and Salford RTS and RTS XTR at my farm in northeast Nebraska. The hilly field I tested them in has been in corn at least five years. While each machine performed according to the manufacturer's claims, some worked better than others toward my goals. All the units did a good job processing residue, while anchoring it to the soil. Some tools were too aggressive and turned too much soil. Some did better to prepare a consistent seed bed to a 2-inch depth. I have a favorite, but it's unfair to highlight it, because that is based on what I wanted to accomplish.

There are several brands of aeration machines, including the Aerway, Gen-Till and Smart-Till. I tested an Aerway on a pasture renovation project. It did loosen, aerate and level the soil. I liked what it did so far. However, I haven't yet run it over cornstalks or soybean stubble and can't comment until this fall.

EVALUATE PERFORMANCE

When testing a machine, evaluate performance. At $2,000 to $3,000 per foot of width, these tools are a major investment. How well is the residue processed and anchored? How much soil is turned? Are rootballs untouched, split and flipped out of the soil? Does the tool solve compaction problems? Does it help you easily plant into the seedbed?

A broom helps evaluate performance. Sweep away residue and loose soil 1 to 2 inches deep and look at your potential seedbed. Do you like what the machine is doing?

Once you choose a tool, continue to evaluate performance and make necessary depth, weight and angle adjustments to make sure the machine does what it was bought to do.

Look at emergence in the field. Is it faster and more, and give you better plant stands? If so, mission accomplished.

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Join Dr. Daniel Davidson, Telvent DTN Staff Agronomist, for a free DTN/The Progressive Farmer webinar on Sept. 8. Davidson has tested a number of these new these new vertical tillage and minimum-tillage tools on his farm and will share his experiences and perspectives. Webinar will include the latest university research and video footage of these tools in action so viewers can see how they affect residue. Videos will show the different products in action, as well as have Davidson illustrate how they met his goals. Register at http://bit.ly/…

Daniel Davidson can be reached at daniel.davidson@telventdtn.com

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