March 19, 2003 | By: Laura Skillman

The temperatures finally are beginning to feel more like spring and farmers are looking to their fields in anticipation of planting. Proper maintenance of equipment now can mean less lost time due to breakdowns once planting begins.

Another benefit of properly maintained equipment is an accurate distribution of seed, fertilizer and chemicals that should translate into yield.

“It’s important to have equipment ready to be in the field,” said Tim Stombaugh, University of Kentucky agricultural engineer.

General maintenance such as oil changes and lubrication is important. Any equipment that has sat unused over winter may have sludge buildup showing signs of a dirty carburetor, he said.

Farmers also should check to make sure nothing is seized up in their equipment. Waiting to the last minute can result in a planting delay if they have to remove a bearing and wait for a new part, he said.

Planter maintenance also is important, but each planter has different maintenance requirements. Stombaugh said farmers should follow manufacturers’ maintenance schedules for planters and other equipment.

Proper maintenance of planters can make a difference come harvest time, noted Jim Herbek, UK Extension grains specialist.

“Planter maintenance is important, particularly maintenance of the seed units from the standpoint of getting proper plant spacing,” he said. “Seed units should be inspected, and worn or damaged parts replaced and adjustments made according to the owners manual and then calibrating the units.”

There are two potential corn yield losses because of improper maintenance and calibration, he said. One would be the result of irregular plant spacing and the other from uneven plant emergence because of uneven planting depths and not making proper adjustments for the planting conditions.

“Studies have shown you can have a 5 to 6 percent yield loss because corn plants don’t emerge uniformly,” he said. “Studies also have shown that emergence delays of seven to 10 days can result in that loss and longer delays can further increase yield losses. Even emergence is critical.”

Uneven plant spacing also can cause corn yield loss of 2.5 bushels per acre for each inch of deviation from the proper spacing. Deviations can be the result of plants being too close because an extra seed is dropped, or too far as the result of skips, or a seed doesn’t germinate.

“You are not going to get 100 percent accurate, but probably the ideal goal to shoot for is to have no greater than a 2-inch standard deviation in plant spacing,” Herbek said. “If you are within that you are doing fairly well. But a deviation of three to five inches or more can result in a 7-bushel to 10-bushel per acre yield loss.”

If plant spacing and emergence are both a problem then yield losses could be substantial. Lost yield translates to lost revenue when the crop is marketed.

More and more producers are having their corn planter units maintained and calibrated either through dealers or private businesses, Herbek said. Increased yields from proper spacing and emergence can quickly offset the costs of maintenance and calibration.

Stombaugh also noted that many newer machines contain sophisticated electrical components and wiring can become frayed or the connections can be loose. These should be checked prior to heading into the field.

A moisture check in gearboxes is also a good idea, Stombaugh said. Temperatures over the winter months can lead to moisture buildup which can result in water getting into the oil and causing problems.

 While proper maintenance doesn’t guarantee a breakdown-free spring, it can result in fewer breakdowns and find a potential problem before it becomes serious causing longer delays and more expensive repairs. It also can mean more grain in the bin at harvest.



Jim Herbek, (270) 365-7541 ext. 205; Tim Stombaugh (859) 257-3000 ext. 214