Tips for Retrofitting Your Planter for No-till Dr. John Bradley Conservation Tillage Specialist Monsanto Company Many growers are hesitant to convert to a no-till system because of fears that their stands may not be as good, and that they may be required to purchase new and expensive equipment. However, planting equipment and technology have advanced so much in recent years that good, acceptable stands in no-till are almost guaranteed.
It's not necessary to spend thousands of dollars on new no-till planters to develop an effective no-till system. Instead, add a few attachments and make some adjustments to conventional planters or drills, and you can still get good uniform stands. A conventional planter or drill can be retrofitted for as little as two or three hundred dollars per row unit. Also, Monsanto offers a great rebate on retrofit equipment, up to 20% or a maximum of $1,000 on qualifying retrofit attachments. See your local Monsanto dealer or representative for details. The following items are essential equipment for no-till planters and drills.
Heavy-duty Tool Bar A heavy-duty tool bar is necessary for the extra weight of added attachments such as heavy-duty down-pressure springs and closing wheels. And, it enables the planter to better handle rough field conditions. Most planters and drills should have a 7-inch by 7-inch main tool bar for bearing heavy loads.
Strong Down Pressure Springs Adjustable, strong down pressure springs are necessary to pull each planting unit or parallel linkage toward the soil surface. These springs also ensure that the sometimes hard soil surface does not "ride" the planter out of the soil. Down-pressure is required to hold the planter's depth gauge wheels in firm contact with the soil to ensure a uniform planting depth and reduce bounce. The springs transfer weight from tool bars to row units.
The springs are usually attached to the parallel linkage supporting the row units and may require tightening to ensure proper soil penetration. If the planter is older, you may need to replace the down-pressure springs with new stronger ones or additional springs.
Double-disc Openers Double-disc openers roll and cut through the soil surface to ensure proper seed placement in the soil. The old-style sword or sliding-shoe-type openers are a poor fit for no-till situations because they drag residue and plug seed tubes. Every part riding along the soil surface must first cut through the residue and soil surface, then roll to avoid residue dragging.
Coulters or Off-Set Double-disc Openers Coulters are also necessities on a no-till planting rig. Position one 3/4-inch to 1-inch wide ripple or bubble coulter in front of the double-disk openers. The coulter cuts through the residue cover and works up just enough soil for good seed-soil contact. Set coulters to run one inch deeper than the double-disk openers for "normal" soil conditions. A good "rule of thumb" for coulter setting is: the dryer the soil, the deeper the coulter setting; the wetter the soil, the more shallow the setting.
Coulters are available in several styles and should be selected based on soil, moisture and residue conditions. These styles include ripple, bubble, and wavy or fluted coulters.
Ripple Coulters - This type of coulter penetrates the soil easily, creating a narrow slot. Ripple coulters are primarily used for sod and pasture applications. They throw less soil than other types and work best in heavier soils. Ripple coulters also work well in wet conditions.
Bubble Coulters - Bubble coulters have sharp leading edges that cut residue and push it aside to spread the soil open. This type of coulter works best in sandy soils and dry conditions. However, be aware that they can cause side-wall compaction in wet soils in no-till situations since the bubble pushes the soil apart. Bubble coulters work well in mulch-till systems.
Wavy/Fluted Coulters - There are a number of styles of wavy/fluted coulters. The more waves on a coulter, the more it tills or fluffs the soil. The wavy coulters need to be checked for sharpness after extended use. An 8-wave design is ideal for little soil disturbance at ground speeds faster than six miles per hour. A 12-13 wave coulter provides more tillage at slower speeds. A 24-25 wave coulter leaves a finely-tilled seedbed. Wavy coulters can throw soil out of a seed slot if planting too fast or in wet conditions.
Wider ripple or fluted coulters increase tillage but require more weight to assure penetration. Some no-till operations require 400 to 600 pounds per coulter. To prevent coulters from throwing soil or a pre-plant herbicide out of the seeding slot, select coulters no wider than one inch if planting at six miles per hour or faster. With wider coulters, it's a good idea to reduce ground speed.
Off-set double-disc openers work as well as coulters. The leading disc acts as a coulter to cut through the residue and open the soil for seed placement. In damp residue, such as wheat straw when planting no-till, double-crop soybeans, off-set double disc openers may actually work better than coulters. Off-set double-disc openers disturb less soil than unstaggered, double-disc openers and leave more residue after planting.
Closing Wheels Double-disc openers should be followed by spring-loaded, heavy-duty closing wheels with enough pressure to cover the seed firmly. Spoked or spiked closing wheels, just introduced within the past four or five years, chop or crumble the soil, especially in moist conditions, rather than compress the soil tightly around the seeds. The objective is to provide good seed-to-soil contact and protect seed from herbicides. Seed covering devices and press wheels should cover the seed with soil, not residue. They should firm the soil around the seed, without compaction, and provide a soil surface that is not vulnerable to crusting.
Residue Managers Residue manager attachments may be necessary for high or uneven trash or residue conditions. Residue managers are finger-like attachments, attached to the front of the planter, that are designed to roll at an angle so residue is brushed to either side of the row. By moving the residue, the soil warms faster and the residue does not interfere with seed placement. I recommend residue managers for high residue conditions only. They are not designed to move soil.
Residue managers work best in combination with a coulter. The coulter passes through the soil directly behind the removed residue to loosen the soil without leaving air pockets or compacted walls. The residue manager enables the coulter, disk openers and gauge wheels to operate correctly.
Attachment Adjustment Once your planter or drill is equipped to plant no-till, take some additional time to adjust the different attachments. Don't just set up the planter in your local farm shop, take it out to the field, and expect it to operate properly over a variety of soil, moisture and residue conditions.
Before going to the field, first consult the planter owner's manual and make preliminary adjustments. Final adjustments must be made in the field, based on current conditions. Be sure to check soil penetration and residue management in field conditions. In order to get a good stand, you must evaluate carefully the condition of each field and adjust the planter accordingly, just as you would with a conventional planter or drill. Residue managers should be adjusted independent of other retrofit attachments. Springs and pressure settings should be adjusted for each field, depending on residue, soil moisture and soil type.
Turning a conventional planter or drill into a no-till implement requires a few adjustments and attachments, but it's not an expensive process. Remember, when planting into no-till or conservation tillage conditions, it's always better to be over-equipped than under-equipped.
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