Seed corn dealers are knocking on doors. It's what they do this time of year. Bob Nielsen, Purdue University corn specialist, has some advice for how to go about picking hybrids, rather than just buying form who is your neighbor, or who has the free hats.
Nielsen suggests looking to results from independent or university trials where the plots were replicated. The results should have been analyzed for statistical difference between hybrids. In other words, hybrids that are truly different in yield should be noted by different letters. Sometimes hybrids which are only a bushel or two apart may show that difference simply due to chance. If you planted them again, the odds are just as good that the other hybrid that lost this time could come out on top. You're looking for hybrids that are consistently among the best.
He offers two suggestions on how to find those hybrids. First, look for hybrids that consistently yield 5% above the average of the trial in all trials in which they are entered. That should mean it's a better-than-average hybrid across a variety of conditions. Make sure you get test results from multiple locations.
For example, if the average of all hybrids in the trial is 180 bushels per acre, then pick out those for a closer look that yield 189 bushels per acre or higher. That's 5% more than the average of the trial.
The second approach is to look for hybrids that consistently yield within at least 90% of the top hybrid in the plot. That means any hybrid that yields at least 90% of the hybrid that ranks number one in the plot, producing the maximum yield. It means you're looking for hybrids at the 90th percentile or higher compared to the best out there.
For example, if the highest yielding hybrid in a trial was 225 bushels per acre, look at only those hybrids that yield 203 bushels per acre or more. See if they are consistently within that range in all of the plots that you can find data for. Remember you're interested in replicated, independent plots or trials conducted by university research programs, such as at Purdue University.
These are just two methods that can help you narrow down hybrids that might work for you. If the salesman at the door doesn't have any hybrids that meet these criteria, perhaps he isn't the one that can help you.