Many combines are capable of shelling corn at a moisture greater than 30 percent with minimal losses, which may help producers get an early start on harvesting what promises to be a huge Mississippi corn crop.
But look very closely at the cost of drying corn in the bin, says Herb Willcutt, agricultural engineer, Mississippi State University. “With the cost of energy we have right now, it's not economically feasible to harvest corn at 25 percent moisture or greater and dry it down.
“We're seeing more and more farmers harvesting at 16 percent to 17 percent moisture and in the process of handling it and putting it the bin, getting it down to below 15 percent moisture. For longer term storage, you need to remove moisture down to as low as 12 percent.”
While field drying is more cost-effective than a drying system, according to Willcutt's research, don't forget factors such as an early-market premiums and the benefits of avoiding getting caught up in the glut of corn entering the handling stream.
According to Willcutt, as the big harvest hits high gear, farmers may have to cut a little corn at a time to accommodate long lines at the elevator, which is likely to turn a three-week to four-week harvest into a 12-week stretch. “Trucking and receiving issues are potentially significant. The one good thing is that we can get most of our corn on barges and out of the system before it becomes a major problem from the Midwest corn entering the market.”
Willcutt says use caution when using temporary storage solutions such as large plastic sealable bags of the type used in the Midwest Corn Belt. “It's going to be hot when we harvest. If we put a 15 percent moisture corn in a sealed bag, we're liable to have cool nights, which would make the corn sweat on the inside of the bag, leading to quality loss. There has been some use of the bags in the Corn Belt, but I have not seen any data to indicate whether it's a safe or unsafe method of storage for corn. The equipment is also rather costly. It's not a good long-term solution as evidenced by the number of grain bins we see in the Midwest.”
“The grain bags sound great in Australia, Argentina and Israel, and I hope they work in Louisiana,” says Bill Branch, Extension agricultural engineer with the LSU AgCenter in Baton Rouge. “But we have no experience with them under our weather conditions.”
Branch helped organize a Grain Storage and Drying Workshop at the West Carroll Parish Extension office in Oak Grove, La. More than 60 farmers attended the meeting, which featured a presentation by Ronald Noyes, professor emeritus at Oklahoma State University.
Noyes said growers may have to resort to temporary storage using bulkheads in metal buildings or other facilities, but the grain must still be handled properly if it is to remain in good condition.
Another design, an inflatable bulk storage bag, allows for some aeration, “but the distribution of air is very poor,” says Willcutt. “If you put 12 percent moisture corn in there with a maximum daily temperature of 60 degrees, I don't think you have a problem. But with 15 percent corn at 90-degree daytime temperatures, dropping to 60 degrees at night, you're asking for problems. There is not a good replacement for a good circular grain bin with adequate drying and aeration.”
“Looking forward, growers should decide if corn is going to be a major part of their rotation with other crops, and if so, consider making a long-term commitment to storage,” Willcutt said. “It's too late right now, we have to make the best of what we have and live with it. But this market could be around for a long time, and corn fits well into a rotation with cotton.”