WEST LAFAYETTE, Ind. — Cool, rainy weather is posing a host of challenges – including potential crop damage – for Indiana farmers statewide during fall harvest. Even farmers in the northern part of the state where the often-sandy soil drains quickly are being kept out of fields in some areas.

Bill Field, a professor in agriculture and biological engineering at Purdue University, said spoiled grain is one of the dangers from having such a cool, wet harvest season. He said farmers often rely on leaving wet corn and soybeans out in the fields longer to dry before harvesting and placing into storage.

The cool temperatures and damp weather so prevalent across the state, though, don’t help grain when it is allowed to remain outdoors for extended periods to naturally dry down before harvest.

As a result, Field said there’s a higher risk of grain rotting if kernels with a moisture content above 14 percent are placed into storage, because air piped in from the outside to ventilate silos for drying has been too cool and moist to work adequately in evaporating water from corn and soybeans.

"You cannot put wet grain in a bin and expect it to maintain good condition for very long under these conditions," explained Field.

Grain bin fires are rare, but the odds of having one when grain is stored wet are greater from farmers doing things like overworking their heaters, which can ignite the mold or crust that develops on rotting kernels and walls of the silo, he said.

He said wet grain can also result in greater risk of death for farmers getting their hands caught in augers, from reaching in to break up obstructions in silos caused by the moist kernels clumping together.

Danger is also posed by combines and other heavy machinery used in harvesting getting stuck in muddy soil, and the hazards that go along with using other equipment to free the machines from the ruts.

"You got issues with tow ropes. You got issues with putting an awful lot of stress into these pieces of machinery with people around them. I think we just got to be really cautious about getting into some of these wet fields before it’s really time to get in there," said Field.

Even farmers in the northwestern part of the state near Lake Michigan have not been immune from the wet autumn. As much as 3 inches of rain in a single day fell in some areas in this part of the state recently – an amount that cannot percolate through the sandy soil here fast enough for the ground to remain firm.

Lighter, more consistent, rains that followed have kept the ground in areas like LaPorte, Starke and Porter counties pretty moist, although conditions have been good at times to harvest even soybeans – which last week had an ideal 12 percent moisture count when brought in from the fields, said Gene Matzat, an educator with the Purdue extension office in La Porte.

Soybean growers have to be especially careful, though. Unlike corn, which doesn’t take in additional moisture after reaching maturity, soybeans are hydrophilic, meaning they absorb moisture after maturity and can burst if left in the fields during rain or while in storage, said Matzat.

He said another hazard of using heavy machinery in these saturated conditions is the ground becoming too compacted for future crops to grow properly. Compaction even in sandy soil causes water to pond for longer periods of time, flooding crops and making it difficult for roots to take hold deep enough in the soil, which can lead to poor quality and even death of the plant.

"Soil compaction can be a problem that takes several years to mitigate and rejuvenate," warned Matzat.

Storing wet grain also carries a financial impact from the added cost of gas and other fuels to operate heaters for drying down the corn and soybeans. "The rain isn’t helping a lot with the harvest," quipped Matzat.