Drying Corn in the Field or with Heated Air – What Are the Trade-offs?
Midwest, which is five percent. With this year’s predicted new record average yield for Kentucky (181 bu/ac) and current average cash price ($3.60), average harvest losses amount to $33 per acre. If harvest losses were reduced to two percent or increased to eight percent by stalk deterioration or heavy storms, the costs would be $13 and $52 per acre, respectively.
By Sam McNeill, Ph.D., P.E. Associate Extension Professor Food and Bioprocess Engineering
Compare these to the costs of drying, which depends on the incoming corn moisture, energy efficiency of the dryer, and cost for fuel (LP or natural gas). An average drying efficiency for new and existing grain dryers is around 1750 Btu/lb of water. If LP costs $1.00 per gallon, the cost to dry corn to 15 percent moisture from harvest levels of 30, 25 and 20 percent moisture would be $40, $31, and $18 per acre, respectively. This range of values is anticipated this
Should you dry corn in the field or with heated air? What are the trade-offs? The answer depends on grain and energy prices, the number of days to complete harvest, weather and crop conditions as corn remains in the field, and the amount of machine losses that will occur during harvest. If dried in the field, stalks can weaken and/or become lodged, which can lead to increased pre-harvest losses (ear drop); a slower ground speed for the combine (to reduce header losses); and a longer harvest period (which can compound both losses). While harvest has begun in the western part of the state, it won’t be in full swing for the rest of the state until mid-September this year. Measuring Harvest Losses To answer the question for an individual farm, you need to know how to measure total harvest losses and strive to keep them below the average level reported for the
UNIVERSITY OF KENTUCKY
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