Recently, Dr. Marcelo Wallau, University of Florida Forage Extension Specialist, spent some time at Auburn reviewing our cool-season variety trial data and discussing the results. Much of his discussion with Dr. Leanne Dillard, Auburn Forage Extension Specialist, and myself was recorded for his podcast “Cow Talks” and is available for anyone interested.
Auburn University Variety Testing does NOT make variety recommendations. The program provides unbiased data for stakeholders to make educated, data-based decisions when selecting a variety.
For the discussion with Dr. Wallau and Dr. Dillard, we looked at ryegrass varieties with at least 3 years’ worth of data and focused on “Top Yield Group.” For individual trials, varieties are split into two groups. The first group is statistically NOT different from the best value. This group is given a value of 100% in the top group. The second group is statistically different from the best value and is not in the top group, 0%. For multi-year and/or location data, these values get averaged and show the percentage of time that the variety was in the top group. This helps show consistency across locations and time.
The link below will show the ryegrass dataset that was used for the discussion. Pay attention to the tabs at the top of the page. There are tabs for the North, Central, and South Regions of Alabama plus a “total” tab which is statewide. As a result of the December freeze, the North Region dataset is using data prior to 2023.