What a season this has been! And for better or worse, we dealt with the fallout. After excessive moisture early on, we were plagued with long dry spells. It has certainly been a year to remember, or at least one to take a lot of notes on.
Throughout the season, I heard growers refer to this year as an insurance crop. Although that may be true and a common mindset, there is still a lot to take away from this year. I am sure you haven’t even begun to think much about the mailbox full of plot results yet to come from yours truly, and probably a few other seed companies. With that said, what are you hoping to take away from plot data? Have you thought much about what you want to learn from your management practices? With the extreme variability in conditions that were thrown at us this year, I’m wondering what realistically can be gained from plot data this year.
How many times have you had a seed sales rep in your combine showing you yield data where their hybrid outperformed whatever it is you are harvesting? All you want to tell them is that a blind pig finds an acorn every once in a while. The most dominant hybrids, and you know which ones they are, only truthfully win 70%-85% of the time. The hybrid that “won” the plot doesn’t tell the whole story. Pay close attention to trends in the data as well as the plot’s location. Is this plot even relatable for you? Test plots are a wealth of valuable data, as long as you look beyond the “winner” and “losers”.
Let’s dive deeper into plots. More knowledge can be gleaned from a challenging year (like this one) than one that’s “normal” or average. This year will allow us to look deeper into the effects of late planting, wet planting, nitrogen loss, stress emergence, and cold snap. Plot data publishes yields-by-hybrids like a drag race in terms of premium yield performance, but I encourage you to dive a bit deeper. Even more important this year than ever, we can’t just compare all plots against each other, like apples to apples. Beyond the traditional conditions that vary, like soil type and rainfall, the extreme difference in planting dates this year can be misleading.
On top of this year’s unique challenges, always keep in mind not all plots are created equally. Factors such as rainfall, soil fertility, diseases, and insects will always vary across each plot, and their effect on the individual location needs to be considered. But how? Assume each factor affects every hybrid similarly. By combining multiple plots, you can develop the least significant difference, (LSD). The LSD is used to judge the likelihood of whether the difference you are looking at is significant or not. But unless you have a whole stack of plots you really cannot calculate this number. That number will be found on all university trial data and is also found in most large data sets. Take advantage of the work statisticians and number crunchers have done for you: evaluate the least significant difference value to determine if the data is significant to you and your ground.
As you comb through the plot data this fall, take a moment to look at and understand all of the data, not just yield. While the growing conditions were not ideal, this spring and summer presented a unique opportunity to see what kind of stress the hybrids can stand up to. Consider these extreme conditions and ask, how is this plot data helping me better farm? If it isn’t, it’s just noise.