Along with yield and moisture, growers most often discuss the test weight of the grain they are harvesting. Grain moisture is important because of cost of drying but why is test weight important? Here are some facts about test weight and why it is important:
• Test weight of grain is a ratio between weight and volume. It is measured as weight of grain that fills a quart container. There are 32 quarts in a bushel basket.
• Corn grain is marketed in the U.S. on the basis of 56 pounds test weight per bushel.
• The corn with 56 pounds per bushel is considered No. 1 yellow corn and 54 pounds per bushel is called No. 2 yellow corn at 15% moisture.
• Along with bragging rights, farmers can haul more bushels of high test weight grain in the truck per trip to the elevator than low test weight grain.
• Grain with lower than 56-pound test weight is discounted by the elevators, but no credit is given for higher test weight.
• Grain with higher test weight generally has better quality.
• There is no correlation between test weight and yield potential of a hybrid, though hybrid genetics plays an important role in test weight determination.
• As the moisture goes down, test weight increases since dry matter of the grain weighs more than the water.