When soils are wet, donning the right mental attitude can help to beat the elements, says Mark Hanna, Iowa State University Extension agricultural engineer.

Due to a cold, wet start to spring, farmers should keep in mind that 2008 will likely be an imperfect planting season that will require good mental preparation, he says. Those who try to operate in soils that are too wet will risk compaction, smearing, clods, uneven emergence and lower yields.

“This year, you’ll probably want to limit the amount of spring tillage that you do, particularly if soils are wet and bordering on plastic,” says Hanna. “If you take up a handful of soil and squeeze it and the soil doesn’t spring back, but stays in a ball like silly putty, then the soil is plastic and too wet for field work.”

Plastic soils don’t till well, nor do silly-putty soils make good seedbeds. However, as the window begins to close on the planting season and soil conditions remain challenging, farmers will have to decide whether the risk of lower yields from late planting outweigh the risks from operating equipment in less-than-ideal soil conditions.

“Controlled traffic is a distinct advantage to farmers in a spring like this one,” says Hanna. “It may be too late for this year, but as you update your machinery in future years, try to make updates with controlled traffic and precision farming in mind.”

If soils remain too wet for field operations, however, farmers should use the time to review owner’s manuals, particularly for the planter, to see what adjustments might need to be made for different soil conditions, he advises. “For example, if soils are on the wet side, then you’ll need to go easier on the down pressure of the closing wheels behind the seed opener, or you could just put them in the float position,” says Hanna. “Switching from rubber-coated, aluminum closing wheels to spade, spike or finger wheels might be another consideration to avoid over compaction from wet soil conditions.”

Farmers should also go easy on the down pressure springs or the pneumatic system that transfers weight to the row units if soils are wet. “The two depth-gauging wheels need to be in firm contact with the soil, but don’t overdo it and risk compaction,” he says. “You only need a little bit of pressure to maintain contact with wet soil.”

Another way to avoid compaction is to ensure your tractor tires are inflated at the correct pressure for the axle load they are carrying, says Hanna. However, fine tuning the planter is an often-neglected task that can be essential to prevent compaction in the seed zone and uneven emergence problems, which tend to decrease yields during a wet spring, he emphasizes.

“In wet soils, it won’t be business as usual,” says Hanna. “Any time soil conditions change, you’ll need to make adjustments to your planter. So, make sure to get off the tractor and check the settings, especially in the first field that you enter, but also as you move from one field to another.”

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