Comparison of Combine Grain Loss Measurement Techniques

Combine tests were conducted in commercial rice fields at Keiser, Arkansas, in 1990 and 1991. As a part of these tests, total grain yields were calculated from data collected with a commercial combine and a plot combine. Loss rates were estimated and compared using two techniques. The first technique used the total grain yield determined from the commercial combine to calculate loss rates. The second technique used the total grain yield determined with the plot combine and the amount of grain collected in the grain tank of the commercial combine to calculate loss rates. Differences of as large as 50 percentage points were observed in some test runs between the two techniques. Because of the large errors experienced in calculating loss rates when estimating total grain yield with the plot combine, it was concluded that this approach was not appropriate for estimating combine losses from test runs of approximately 6 m (20 ft) in length.