It may be a couple months or more before you head to the field, but don’t let this window of opportunity to ready your planter pass by. Most of the prep work and inspections can be done in the comfort of your shop and the remainder after you enter the field and begin to plant.
Before planting season, "inspect everything involved with seed transmission: chains, sprockets, bearings, idlers and clutch assembly, including all of the components involved in seed metering, as well as the meter itself," advises Farm Journal Associate Field Agronomist Missy Bauer. "Even if you have your meters calibrated, if there is any vibration in the system, it will have effects throughout the planter. Everything is hooked together."
Bauer draws on her experiences and shares practical pointers at five Corn College Planter Clinics to be held from Mississippi to Minnesota this winter.
Here’s what Bauer looks for when she inspects transmissions and row units in the shop and after she takes the planter to the field.
Transmission. "I’ve seen clutch assemblies so badly worn that they make a big jump as they turn," Bauer says. "That can cause skips about 1' wide all the way across the planter. After emergence, you will see that pattern throughout the field. But you won’t pick it up in the monitor as you plant. The seeds are still being planted, and you will get the right population, but there will be big gaps."
Even one frozen link in a drive chain will cause the chain to jump every time it passes through the rollers, Bauer says. Some chain problems are easy to spot, but others are less obvious.
"Find a small motor like those used to calibrate dry insecticide, hook it to the main driveshaft and spin the planter," she says. "With the planter boxes off, run the planter and look for frozen links or problems with idlers or rollers. Keep the chains lubricated."
As you spin the planter, look for bearings that are going bad. "You can check bearings by taking a long screwdriver, placing the tip on the bearing housing and holding the other end to your ear," Bauer says. "Bearings that are beginning to fail will have a gravelly sound. You want to find problem bearings before you’re in the field because if one fails during planting season, fixing it can cost a lot of time."
On many newer, bigger planters, Bauer finds that the sections of the main driveshaft do not line up properly when the planter is unfolded. That creates variation in the system.
"Sometimes we find differences in the rpm of two shaft sections," Bauer says. "If that happens, the plant population will increase and decrease as you plant across the field. So if you have a bigger planter that folds out, check the driveshaft alignment."
To inspect the seed meter drive system, spin the drive system with the seed boxes in place but left unlatched. When the system is running, feel each box for vibration.
"Sometimes you can even see the vibration," Bauer says. "It indicates a problem where the seed meter connects to the driveshaft—the two shafts are not lined up."
"If you run starter fertilizer from a squeeze pump on your planter, it’s important to set the system up independently from the seed transmission system," Bauer advises. "You don’t want to introduce variability into the seed transmission system from a pulsating squeeze pump."
Whether you run a finger meter or a vacuum meter, calibration is extremely important, Bauer says. "Calibration stands are common, and it’s not expensive to get calibration done. Have it done every year using seed of the shape and size you will plant."
Row units. Center the row units. "Use a tape measure to mark a known point on the main toolbar out from the row unit," Bauer says. "Run the tape back to a known point on the row unit. Measure each side and make sure they are close; if they aren’t, you have a twist. Sometimes you can bend the units back straight; if not, you need to replace the main part of the unit."
To check parallel linkage, grasp the rear of the row unit and try to jerk it up and down. "If there’s play, try to tighten the bolts," Bauer says. "If that doesn’t work, take out the bolts and examine the threads. If the threads are worn, replace the bolts and bushings.
"If you do a good job of keeping the bolts tight, they will last a lot longer," Bauer adds. "If you have been planting for a few days and get a rain break, go through the planter again and retighten the bolts; you’ll be surprised how loose they get after planting a while."
Left uncorrected, loose bolts will cause the bolt holes for the parallel arms to wear and become egg-shaped, rather than round.
"If that happens, new bolts won’t help," Bauer says. "Then you may have to replace the parallel arms. Those arms help keep row units from bouncing."
In a study, Bauer compared three reconditioned units to three worn ones. "From the tractor, you could acutally see that the worn units bounced around more," she says.
Row cleaners. The purpose of row cleaners is to help achieve uniform emergence by removing residue, rocks and clods from the path of the row units. "If you have a lot of residue and no row cleaners, residue will get pinched into the seed trench. That causes nonuniform emergence, which leads to a reduced ear count," Bauer says.
Bauer recommends running row cleaners even in conventional tillage. "Row cleaners can increase ear count by 600 ears per acre in conventional tillage with a corn-soybean rotation," she says. "An additional 1,000 ears per acre translates into 5 bu. to 7 bu. more. In conventionally tilled continuous corn, row cleaners can increase ear count by 1,500 ears per acre."
No-till coulters. In order to create a true V-shaped trench and drop seed in the bottom of it, no-till coulters must be properly set. "If no-till coulters run too deep, you may create a loose or false bottom in the trench," Bauer says. "Seed falls into the loose soil, and you get uneven depth. A ¼" difference in planting depth can determine whether or not a plant makes an ear."
To properly function, a no-till coulter should run at least ¼" above the bottom of the double-disk openers. There are two ways to set coulters.
"If you have a smaller planter, while still in the shop, raise the hitch high enough to level the main toolbar. Stick a second level under the double-disk openers and measure the distance between the top of the level and the bottom of the no-till coulter. If you don’t have at least ¼", raise your no-till coulter. It is critical that the main toolbar is level during this process.
"If the no-till coulter is as high as it will go, but still not high enough, loosen the bottom two bolts and insert washers to give the unit extra pitch."
If your planter is too large to unfold in your shop, Yetter Manufacturing makes a tool called the 1200 Series Checker to set your no-till coulters.
Gauge wheels. Depth-gauge wheels must be set firmly against the double-disk openers. "If depth-gauge wheels run loose in dry conditions, dirt can flow into the mechanism and fall out into the seed trench," Bauer explains. "If you drop dry dirt on top of the seed, you will have problems with uniform germination and emergence, which will reduce your ear count. If the soil is wet when you plant, the wheels collect mud on the inside and won’t properly turn."
To check gauge wheels, "push them into the up position and pull out on them," Bauer says. "See if there is any space between the disk opener and the gauge wheel, to the point that when you drop the gauge wheel down, you can hear and feel it rub against the disk opener.
"Jerk back and forth on the gauge wheel and see if you find play in the shaft. If the shafts are so badly worn that you can’t tighten them, rebuild kits are available."
A Depth-A-Matic device, which fits Kinze and John Deere planters, lets the two gauge wheels move independently. That prevents the opener from being pushed out of the ground if one depth wheel hits an obstacle.
Disk openers. If disk openers are not set properly, you will get a W-shaped bottom in your seed trench and seed will be placed at uneven depths, resulting in uneven emergence.
"Brand-new disk openers are 15" in diameter," Bauer says. "Replace them when the diameter falls to 14½"."
It’s also important to check the point of contact of the double-disk openers. That is what creates the true V-shaped opening you want. "Insert two business cards—one from the top and one from the bottom," Bauer says. "Push them toward each other until they won’t slide any farther. Measure the distance between the cards. Check with your planter manufacturer for the proper point of contact—it may vary from 1" to 2" to 2½" on different models."
Take this measurement four times around the blade. If you can’t achieve the proper point of contact by moving shims, the blades are either warped or worn too small.
Seed placement. "When seed tubes get worn, often on one side, it creates a ‘dog ear,’ which causes misplaced seed," Bauer says. "If that is happening, you need to replace the seed tube."
If you replace a seed tube, replace the guard, also. Worn guards wear out seed tubes. Bauer likes to see guards run close to the seed tube, where they provide maximum protection.
"Seed firmers push the seed into the trench, helping provide good seed-to-soil contact and uniform depth," Bauer says. "A 1⁄4" difference in planting depth makes a big difference in ear size; often, you won’t see an ear at all on the later-emerging plant."
Seed firmers also provide a way to deliver pop-up fertilizer to the furrow.
"Check for wear at the bottom of the seed firmer," Bauer says. "Worn firmers get rounded on the bottom; they may actually flip seeds out of the trench, especially if you’re planting in abrasive soil."
Ask the person who sold you your seed firmers how to adjust the screw that sets the tension.
Closing wheels must be centered over the seed trench. "If they aren’t centered, they won’t do a good job of closing," Bauer says. "The trench will be sealed on top but still open on the bottom. If the soil dries out, the slot will open up."
To check alignment, Bauer recommends setting your planter down on a concrete surface and driving forward. Look for the scratch line from the double-disk openers to be centered between the closing wheels. Yetter’s 1200 Series Checker tool can create a line you can use to center the planter’s closing wheels. This test also gives you a chance to check the alignment of starter fertilizer openers running beside the seed trench.
In-field settings. "You can have everything else set right, but if your planter is not running level in the field, it will cancel the effect of everything you’ve done," Bauer says.
In the field, Bauer places a level on the main toolbar and walks alongside the planter, watching the bubble as someone else drives the tractor.
"If the planter isn’t level, adjust the height of the hitch," Bauer says. "On bigger planters with a three-point hitch, it’s pretty easy to make adjustments. On smaller planters with a standard hitch style, we often place washers above the drawbar to help keep the hitch where it needs to be. On some planters, there are adjustments you can make in the height of the hitch coming off the tongue."
Another way to waste all the effort you’ve put into tuning a planter is to drive too fast. "Planting speed should be 4½ to 5 mph," Bauer says. "If you can’t get your corn planted in five to seven field days at that speed, you need a bigger planter."
Doubles, skips and misplaced seed reduces your ear count. "With uneven seed placement, you can lose 10 bu. to 20 bu. per acre easily," Bauer says.
Another in-field adjustment that can be tricky to set just right is down pressure because it varies depending on planting conditions.
If you properly prepare your planter, maintain its performance during the season and drive at a reasonable speed, your final ear count should add up to be within 1,000 to 1,200 of your target population.
"If it isn’t, you’re leaving too much yield in the field," Bauer concludes.