A clean, insect-free storage facility is vital.
Some grain will be stored for many months or even more than a year due to low grain prices, so maintaining grain quality during extended storage will require extra care and management, according to North Dakota State University’s grain storage expert.
“Grain that will be stored for an extended time needs to be good-quality grain,” says NDSU Extension Service agricultural engineer Ken Hellevang. “The outer layer of a grain kernel is the pericarp, or seed coat, and provides protection for the kernel. If the pericarp is damaged, the kernel is more susceptible to mold growth and insect infestations. This reduces the expected storage life of the grain.”
Broken kernels and foreign material should be removed by cleaning the grain before storing it. Segregation based on size and density occurs as grain flows into storage. Fines accumulate in the middle unless a functioning distributor spreads them throughout the grain. Unloading some grain from the center of the bin will remove some of the fines and help level the grain in the bin.
Also, immature kernels have a much shorter expected storage life. Grain test weight may be an indicator of maturity and storability.
Assure that the storage facility is clean and insects are not living in aeration ducts, under perforated floors, or in handling equipment or debris around the facility. Fumigate the empty bin to kill insects under the floor or in aeration ducts if an infestation occurred during the previous year. Also, consider applying an approved residual bin spray and a grain protectant to repel potential insect infestations if storing grain during warmer portions of the year.
Mold growth requires moist conditions, usually above about 70 percent relative humidity, and warm temperatures. To reduce the potential for mold growth, the grain moisture content should be below the equilibrium moisture content (EMC), at 60 to 65 percent relative humidity.
The EMC of corn at 70 degrees and 65 percent relative humidity is about 13.5 percent, and at 50 degrees, the EMC is about 15 percent. If you can keep stored corn below 50 degrees, you can store it at 15 percent moisture. But if the temperature will be warmer, then the recommended storage moisture content is about 13.5 percent. Equilibrium moisture content charts for various types of grain are available on the internet.
Hellevang also has this advice for long-term grain storage:
-Check the grain at least every two weeks until it has been cooled for winter storage and every two to four weeks during the winter.
-Verify that the moisture content is at the recommended storage level.
-Check the grain temperature.
-Inspect for insects.
-Look for indications of storage problems such as condensation on the roof.
“Using temperature cables or sensors to monitor grain temperature is encouraged, but remember that because grain is a good insulator, the temperature can be different just a few feet from the sensor,” Hellevang says.
(Source – http://cornandsoybeandigest.com/marketing/long-term-grain-storage-requires-good-management)