Ohio Corn Performance Test 2025: Covington, early maturity

Compare commercial corn hybrids submitted by seed companies under identical management, so that differences in yield, harvest moisture and test weight can be attributed to the entry rather than to the field.

Production system. field.

Analysis. Yields are corrected to 15.5 percent moisture, which is what makes entries harvested at different grain moistures comparable at all. Harvest moisture is reported alongside because it carries a real cost the corrected yield hides: the test itself charges a drying penalty for every point above 15.5 percent.

Grain yield corrected to 15.5% moisture. Plot grain weight converted to bushels per acre and corrected to 15.5 percent moisture, the US commercial standard for shelled corn. The correction is what makes two plots comparable: grain harvested wetter weighs more for the same dry matter, so an uncorrected bushel figure measures the weather at harvest as much as the hybrid. A yield quoted without its moisture basis is not a figure that can be compared with anything. Standard: Ohio Corn Performance Test evaluation procedures.

Grain moisture at harvest. Moisture content of the grain as harvested, before drying. Reported alongside yield because it carries real cost: the same test charges a drying penalty for every point above 15.5 percent, so two hybrids at equal corrected yield are not equally profitable if one comes off the field wetter. Standard: Ohio Corn Performance Test evaluation procedures.

Test weight on grain at field moisture. Bulk density in pounds per bushel, measured on grain at field moisture rather than after drying. Because the measurement is taken wet, test weights from trials that dried their samples first are not directly comparable with these. Standard: Ohio Corn Performance Test evaluation procedures.

Final stand count. Plants per acre standing at harvest, reported by the test in hundreds per acre. In this trial the seed company chooses the planting rate for its own entry, so final stand is a property of the entry as submitted rather than a constant of the trial. Standard: Ohio Corn Performance Test evaluation procedures.

This trial grew 80 entries. AMSeed publishes results for 4 of them. 76 of the remainder are simply not recorded here yet: the source publishes them and we have not transcribed them, which is unfinished work rather than a judgement about the entries. The point of stating the total is that the trial is represented as what it actually was rather than as the slice we happen to cover.

One site in one season. The test reports three replications at this location, which controls for field variation within Covington and says nothing about how these hybrids behave elsewhere or in another year. Entries were planted at rates their own seed companies chose, so a comparison between two hybrids here is a comparison of entries as submitted, not of genetics at matched population.