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There's a new tool available to help plan when to run the fan for drying and cooling grain for long-term storage. The tool predicts air temperature and relative humidity and includes the corresponding equilibrium moisture content for corn or soybeans for the predicted air conditions. Equilibrium moisture content is the moisture content that would be reached if the grain was exposed to the given temperature and humidity for a long period of time.

To find the new tool, go to the AgEbb website at http://agebb.missouri.edu, click on 'Missouri Agricultural Weather' then on 'Horizon Point' or go directly to http://agebb.missouri.edu/horizonpoint/. Horizon Point provides a wealth of weatherrelated information, providing both historical and predicted precipitation and temperature data, a wind forecast, estimated rainfall that might cause runoff based on your soil type, cattle and poultry stress indices, seasonal items such as spring planting soil temperature charts, weed scouting aids, and links to other information. The information available via Horizon Point will only continue to grow as new tools are developed.

November and December are often an excellent time to plan your last cooling period for grain stored for the long-term. For example, the average temperature in a recent Horizon Point e-mail report for my location is somewhere between 28 and 43 degrees. Add a couple of degrees for the natural rise in temperature of the air from the fan motor and grain aerated during this period will reach an average temperature of maybe 37 or 38 degrees F. We always recommend that the last cooling cycle should bring the temperature of the grain down to about 35 degrees.

As I scan the report, I also note that equilibrium moisture contents for corn throughout the day are 16.5, 17.8, 18.5, 17.3, 14.7, 13.5, 16.8 and 17.4 percent. I can rest assured that little or no drying of corn will occur since the average equilibrium moisture content for corn for the current report is well above 15.5 percent. If I know the grain is already plenty dry, I'm probably going to run the fan now to do some cooling. No significant re-wetting is likely to occur. If moisture content is still above 15.5 percent and I want to dry the grain a little more, I may wait for a day when those equilibrium moisture contents are below 15.5 percent on the average or I may run the fan intermittently, probably during the afternoons, when the air is typically drier. I'll just keep watching my e-mail reports for the day that suits my needs best.

More information about the significance of the properties of ambient air in drying or cooling grain is available at http://ag3.agebb.missouri.edu/horizonpoint/examplereports/report_m_more.asp. Your first Horizon Point reports may take a couple of weeks to arrive, but then will reach you regularly at the intervals you specify, so sign up now for your Horizon Point e-mail reports. Then when spring planting is on the horizon, Horizon Point will also provide you with soil temperature information and weed scouting aids.

My final note is to ask you to stay safe when inspecting grain bins and moving grain. If you have any questions about the safety of a particular situation, call me and talk it over before dealing with a bin that may have spoiled grain.

Bill Casady
573 882-4370