Get Ready: Tillage

Tillage experts offer advice on how to prepare the ultimate seedbed with fewer trips to the field. By Des Keller

By Des Keller

“It doesn’t take that much longer to do it right.” We’ve all heard a version of that old adage, often followed by something like, “It’ll sure take less time than cleaning up the mess you made.”

As most producers will tell you, it’s an old saw that certainly applies to tillage. Taking the time to properly calibrate your equipment will not only save you time in the long run, but also save fuel and your equipment from unnecessary wear and tear, as well as help maximize your yield potential by creating a better seedbed.

No matter your goal—residue management, to lessen compaction, seedbed preparation or a combination of them all—a properly adjusted implement will result in fewer trips to the field, better management of the quality and performance of the next crop, and lower potential erosion. So, to help make it all the easier, what follows is advice from two experts on how to get the most from your tillage equipment.

  • Pairing Tools and Speed. Don’t overpower the tool. “A general rule is 8 to 10 HP per foot to pull a tandem disc harrow at 5 to 6 mph,” says Larry Kuster, AGCO senior product marketing manager. “While some tillage tools allow faster speeds, going too fast can create ridges and furrows. Too much speed can also cause tillage tools to bounce, producing an inconsistent tillage depth.”
  • Adjust Tongue to Match Drawbar Height. To optimize fuel use and minimize wear on parts such as the drawbar, it’s important to keep the tillage tool level and moving smoothly through the field. A straight line of draft to the tool is the goal. To do this, match the attaching point of the tongue to the tractor drawbar height to level the frame. Mark Hanna, Extension agricultural engineer at Iowa State University, explains that improper setup can also hamper seedbed prep. “If the implement frame operates ‘nose’ down or ‘tail’ down due to the tongue height adjustment for the drawbar, this can cause the front or rear of the implement to dig in excessively,” he explains.
  • Level the Tool. To ensure it will work the soil at a consistent depth, without gouging or ridging, make sure the tool is level from side to side and front to back.
  • Side to Side. Wings and center frames should operate at the same height. “To check these,” says Kuster, “lower the tool to the ground, stopping the descent when the disc blades are close to the soil but not touching it. Measure the distance from the bottom of the frame to the center of the pivot pin on the walking tandem or, if a single or dual wheel is present, the top of the wheel spindle. The measurements should be the same. Always check the center-section wheels left and right to ensure the integrity of the center lift assembly.

  • Front to Back. Adjust the fore/aft level so the front and rear blades are of equal distance from the ground. “This is a preliminary adjustment,” Kuster says. “Once in the field, confirm the fore/aft level after traveling several hundred feet with the tool lowered in the working position.” Check the soil at the center rear of the tool, where the soil is returned by the rear gangs. A tool that is level front to rear will produce a complete and level fill of the valley cut by the front gangs. If soil forms a valley, the rear of the tool needs to be lowered. If a ridge is present, the rear of the tool is too deep, and the tool should be adjusted to lower the front of the machine.

  • Field Check. Adding to Kuster’s suggestion to check the field for signs of uneven operation, do a visual inspection to make sure your equipment is operating like you need it to. Do this after you finish your first pass in each field or after soil conditions change.
  • Check Tire Pressure. “In theory,” Hanna says, “you want equal air pressure in tires; otherwise, if there’s a slow leak, operating depth becomes deeper on that side.”
  • Purge Air from Hydraulic Lines. With the implement’s hydraulics connected to the tractor, raise and lower the implement several times to allow the system to cycle fully. Because air in the hydraulic lines can allow the wings to sag, this step ensures the wings stay level with the machine’s center section.
  • Gauge Wheels. “These are important on flexible tillage tools to prevent front-wing corners from gouging,” explains Kuster. “When set correctly, these wheels should move slightly side to side when kicked.” A tape measure can be used to ensure the setting for both gauge wheels is consistent.
  • Set Tillage Depth. A general rule of thumb for tillage is to set the depth of an implement such as a disc harrow at 25% of the blade diameter, says Kuster. So a disc harrow with 24-inch blades should be set to till no more than 6 inches deep. “Sunflower disc harrows have a single-point depth control with a convenient hand crank that adjusts the depth in ½-inch increments each time the handle is rotated one turn.”
  • Check Parts for Wear. “Wear replacement is usually from a visual assessment of the point or sweep, or measuring disc radius or diameter,” Hanna says. “It’s good to remind operators to consider this and look over equipment going into the season.”