December 12, 2002
Written By Kent Thiesse, U of M Extension Service
(507-389-8141)
Farmers Urged To Check Grain Bins
Farm operators are urged to check their grain bins for "hot spots" and heating in the grain. Wide temperature variation in the past few weeks could cause 2002 grain that is in storage to heat and could go out of condition, if not addressed properly, according to Kent Thiesse, University of Minnesota Extension Service.
Thiesse said the extreme weather conditions that have occurred this Fall have led to some of the grain storage problems. Most of the 2002 grain was harvested during October and placed in the grain bin when outside temperatures were fairly cool. We then had above normal temperatures during early November, cold temperatures in late November and early December, followed by above normal temperatures. If that grain has not been properly cooled down and the grain temperature equalized in recent weeks, problems could occur.
Thiesse points out that as outside temperatures decline, grain on the surface and near the bin walls is much cooler than the grain in the internal portions of the bin. When a wide temperature variation in the grain happens, moisture migration can occur, which ultimately leads to the grain heating and the formation of "hot spots" in the grain.
Thiesse says the moisture migration can occur even if the grain is dried down below 15 percent moisture, if the grain temperature is not properly equalized. If we get periods of extremely cold temperatures after the recent very warm temperatures, there can also be problems, even if grain was properly cooled down earlier this Fall. It may be a good idea to re-cool the grain in the bin to stabilize grain temperatures.
Following extremely cold temperatures, fans should be run periodically when outside temperatures warm up to equalize the grain temperature in the bin. The University of Minnesota recommends maintaining Winter grain temperatures at about 25 - 35 degrees Fahrenheit. Grain temperatures should be gradually warmed up in the Spring, starting in mid-March, to again avoid a wide temperature variation in the grain bins during April and May.
Thiesse encourages farmers need to take immediate action, if the grain is starting to heat. Fans should be turned on to move air through the grain in order to stabilize the situation. If grain is still heating, some of the grain may need to be removed from the bin and either placed back in the bin or hauled to market. If there appears to problems in the entire bin, it may be best to remove all the grain from the bin to avoid major losses in grain quality.
Producers that have grain storage questions should call their County Extension Office for more information.