More high-moisture moldy corn went through combines this fall than most years, creating storage concerns for many Corn Belt farmers this winter and spring, according to Ken Hellevang, North Dakota State University Extension engineer.
“In-field molds weaken kernel integrity and make it more susceptible to storage molds,” says Hellevang. “Field molds can also damage kernel surfaces.”
To help farmers overcome storage problems when dealing with potentially moldy or damaged corn, Hellevang and Robert Hansen, Ohio State University research scientist, provide these following five top tips:
“We can handle high-moisture content and poor-quality corn as long as we keep it cool enough,” says Hellevang. “Allowable storage times double for every 10° we cool it.
“Typically, the goal in northern states is to maintain grain temperatures in the bin somewhere between 20° and 30° F for winter storage,” he adds. “In states farther south, the goal is to attain a grain temperature between 30° and 40° F for the winter.”
Cool corn is key to quality corn, emphasizes Hellevang. “More grain goes out of condition because we don't control the grain temperature,” he says, “than for any other reason.”
“The purpose of aeration is to maintain the correct temperature over time,” notes Hansen. “Without aeration, hot spots can develop in the bin that cause mold to grow and corn to deteriorate.”
Poor aeration leads to many problems, concurs Hellevang. “Especially heading into spring, both the rising outside temperature and a low solar angle will start to heat up grain if aeration is neglected,” he says. “The solar energy hitting the southern wall of a grain bin in February is two to three times the solar energy hitting the bin in June.”
“Moisture content will determine the intensity that you need to monitor the grain and provide aeration,” says Hansen. “In Ohio, corn that's in good condition at 20% moisture content can be stored from Nov. 15 through March 15 with less than 0.5% deterioration, while corn that is in good condition at 18% moisture can keep safely from Nov. 15 through April 10.” (See table.)
For long-term storage of good-quality corn, farmers should maintain corn moisture content between 13.5% and 14%, advises Hellevang. For poor-quality corn in long-term storage, he advises maintaining moisture content between 12% and 13%.
“Once corn has been cooled to winter storage temperatures, check good-quality corn at least once per month and poor-quality corn about twice per month,” says Hellevang. “As we get closer to spring, check both good- and poor-quality corn every two weeks.”
Farmers should also keep records after every inspection, he adds. “Record your grain temperatures, moisture levels and insect levels,” says Hellevang. “That way you'll be able to detect patterns that indicate quality is deteriorating over time.”
“The best-case scenario is when farmers have an aeration system that automatically turns on when cable sensors detect a significant increase in grain temperature,” says Hansen.
However, even with cable sensors and automated aeration equipment, farmers still need to pay close attention to corn's moisture content and temperature to determine when to sell it, feed it or begin to dry it again, he adds. “Don't wait for a higher price when the shelf life has expired,” cautions Hansen. “That will only lead to more costly problems.”