AgriGold

Drydown & Grain Storage

by Jacob Bates, CCA, October 20, 2009

A long, cool growing season typically results in high yields and 2009 is no different. Unfortunately, however we are looking at harvesting significantly higher moisture corn. As the table to the right  depicts the amount of in-field drying from the middle of October on is very minimal. This will present many challenges not only at the farm but also at your local cooperative and elevator. The biggest of these challenges being, how do we dry down all of these bushels?

Over the past few years many farmers have built or added to their own on-farm storage systems. These grain storage systems along on farm corn dryers will be a huge asset in 2009. Still I believe the majority of the corn crop will be delivered from the field to a local cooperative or other grain merchandiser. When that transaction takes place all grain is graded based on the USDA standards as laid out in the table below. These standards account for test weight, damaged kernels and foreign material. They do not account for moisture and drydown to 15% moisture corn. To account for this each location should post their drying charge and shrink factor.

Yellow Dent Corn Grades and Grade Requirements

The drying charge is pretty straight forward with the cost usually ranging from 4¢ - 4.5¢ per point of moisture removed. The shrink factor is used to account for the weight loss that occurs during the drying process. The shrink factor is expressed as a percentage of weight change per point of moisture lost in order to accurately determine the total cost of mechanical drying. It is derived from 2 components, water loss and handling losses. Water shrink makes up the majority of the shrink factor and is calculated as follows:

Water Shrink Factor %= 100/100– final moisture (dry)

See the table to the right for a list of water shrink factors at various moisture levels.

The second component of the shrink factor comes from handling losses. These losses are usually a small percentage and come from mechanical losses such as broken kernels and foreign material.A typical shrink factor looks like this: Shrink Factor = Total Water Shrink + Handling Losses

Example- 1.40% = 1.176% + 0.224%

Lets work through one example. Say you deliver 44,000 lbs of corn at 25% moisture today at a price of 3.57/bu. The drying charge at the elevator is 4.25¢ per point of moisture and their shrink factor is 1.40%. How much grain will you get paid on at 15% moisture and what will be the price per bushel you get after drying charges?

Equation

1. weight(final) = weight(intial) = weight(initial) * (moisture(final)-moisture(initial) ) * (shrink factor)
2. weight(final) = 44,000lbs = 44,000 lbs * (15-25) * (1.4%)
3. weight(final) = 44,000lbs = 44,000 lbs * (-10) * (o.o14)
4. weight(final) = 44,000lbs = -6160 lbs
5. weight(final) = 44,000lbs—6160 lbs
6. weight(final) = 37,840 lbs or 675 bushels of grain at 15% moisture

Drydown

1. 25% to 15% is 10 points of moisture
2. 10 * 4.25¢ = 42.5¢/bushel
3. $3.57/bu- 42.5¢/bushel = $3.145/bushel

Every cooperative or delivery point of grain should provide you with their list of grain policies and discount schedule. Below is a list of 3 real cooperative’s discount schedules for 2009. As you can see there are some similarities and yet differences amongst locations.

Categories: Corn Harvest

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