A spring oat developed by the Cereal Research Centre (formerly Winnipeg Research Centre) in Winnipeg, Manitoba. It bears the accession name Dumont 68 and OT274 and was tested in the Western Oat Co-op Test from 1993 to 1995. AC Assiniboia was licensed by the Food Production and Inspection Branch in 1996.

A backcross program was used to develop this line. The pedigree is Pc 68 / 7*Dumont.

Based on agronomic, kernel quality and disease data, AC Medallion is well suited for the oat growing areas of western Canada and in particular, the black soil zone of Manitoba and Saskatchewan and the brown soil zone of Saskatchewan and Alberta. In these zones, its yield is equivalent to or better than all of the checks, Dumont, Derby and Cascade.

The lodging resistance of AC Medallion is better than Dumont but poorer than Derby or Cascade. Its maturity is equivalent to Dumont but 1.5 days later than Derby and 4 days later than Cascade. This maturity might limit its area of adaptation. AC Medallion is slightly taller than Dumont but shorter than Derby or Cascade.

AC Medallion has a test weight equivalent to Dumont, less than Derby and greater than that of Cascade. Its kernel weight is similar to that of Dumont and Derby but greater than that of Cascade's. The number of plump kernels is within the same range as all 3 checks; it has more thin kernels than Derby or Cascade but fewer plump kernels than Dumont. The protein content of AC Medallion is similar to all 3 checks. The kernels of AC Medallion have less less oil than Dumont but more oil than either Derby or Cascade. AC Medallion has a white hull.