Set up corn planters correctly
While tractors typically cost far more than the planters they pull, planters are the cheapest thing on the farm for what they do, says Kevin Kimberley, who’s consulted with farmers on planters and tillage equipment for 20 years at Kimberley Ag Consulting.
“You can pull planters with anything,” Kimberley says. “On the other hand, some farmers use a very expensive tractor and won’t spend anything on their planter.”
After 35 years of farming in central Iowa and 20 years of on-farm consulting in the Corn Belt, Kimberley recommends checking seven key things on planters before pulling into the field this spring.
These factors are often overlooked, but are very important: parallel linkages, disk openers, down pressure, gauge wheels, press wheels, planter speed and wing weight.
Parallel linkages. “The more level you can get your parallel linkages, the more even the down pressure will be,” Kimberley says. “Having an even down pressure helps place seed at a consistent depth and spacing.”
Disk openers. When disk openers operate correctly, they work as a true “V,” but there are disk openers on the market that will not make a true “V,” Kimberley says. The disk openers on the planter are at a “V” where they meet the soil, he notes, adding that the gauge wheels pushing down against the disk openers is what forms the true “V.”
“If you don’t have enough down pressure when planting, then you will get sidewall lift, which is the opposite of sidewall compaction,” he explains.
“As a result, you’ll have corn at different depths and spacings because of sidewall lift. When your corn comes up, it will not be in a straight row. It will be side to side. Kernels will germinate early or late and you will get uneven ear placement, which costs you yield and money.”
Down pressure. The “right” down pressure varies because soil conditions change from being hard and dense to soft and loose and wet and dry.
“Just like cars, planters can hydroplane when they have less contact with the soil,” says Kimberley. “If the planter goes from hard to loose soil, you get more hydroplaning. It’s like speeding down the highway. You don’t have the down pressure that you had when you drove slower.” As farmers plant faster, the planters need more down pressure, he notes.
Gauge wheels. In 2006, the shape of gauge wheels on Deere, Kinze and White planters changed. The newer configuration places less down pressure on the soil. “The pre-2006 gauge wheels were flat with a lip to form the true ‘V,’ ” says Kimberley. “The newer gauge wheels have more of an indentation. The result is many planters don’t run enough down pressure rather than too much.”
The newer configuration carries or distributes more of the planter’s weight farther from the disk openers. “That’s changed our old way of thinking about sidewall compaction,” Kimberley says.
“The newer gauge wheels have more pressure farther out from the row. Now, it takes more down pressure for the true ‘V,’ ” depending on soil conditions. Without enough down pressure, there isn’t good seed-to-soil contact, and it causes sidewall lift. As a result, corn plants can be at different emergences and different heights, spacing and be side-to-side.
Planter speed. For the past eight to 10 years, Kimberley has mounted video cameras on planters of all his clients in the Midwest. “These videos show how the row units and the press units on the planter move, even when going at 4.5 mph,” he says. “And 4.5 mph is far less than the standard recommendation of 5.5 mph.”
At 4.5 mph, it’s 7.2 feet per second; at 5 mph, 8 feet per second; at 10 mph, 16 feet per second. “Let the soil conditions determine your planter speed,” he says. “Rough soil conditions can give your planter a rougher ride.”
Wing weight. As planters grew in width to 24, 36 and 48 rows, the wings got considerably lighter. With lighter wings, there can be less down pressure and shallower seed placement compared to row units on the center section, notes Kimberley. Adding weights on the wings can help with this issue.
The amount of weight needed varies, but Kimberley offers these amounts as good starting points:
• 12- to 16-row planters — 300 pounds per wing (More weight may be needed, depending on conditions.)
• 24-row planter —300 to 500 pounds per wing
• 36-row planter — 500 pounds per tire set on the wings
“Under drier soil conditions, more weight is needed on the wings to reduce hydroplaning,” Kimberley advises.
Zinkand writes from Salem, Ore.