What is in this article?:
- Aerial images that show visual patterns in a field can be the first step in discovering problems that affect yields. Follow that up with detailed plant-by-plant analysis on the ground to verify the impact of the problem in yields and more objectively zero in on the problem.
- Aerial photos early or late in the day produce shadows that point out subtle plant height variations; plant height within a field correlates with ear size and yield.
- A close look at plant spacing and projected yields from single ears in a 17-foot, 5-inch span (1/1,000 acre in 30-inch rows) vividly shows planter skips and barren plants are yield killers.
When Bob Recker sees odd patterns in cornfields from the air as he flies across farmland in northeastern Iowa, he can’t wait to land and investigate up close. As owner of Cedar Valley Innovation, Waterloo, Iowa, he uses digital and GPS technologies, along with well honed engineering analytical skills to identify yield-loss problems.
Since retiring from Deere, he encourages farmer/clients to “Fail fast, often and cheaply.” There are no failed experiments if you learn from each one, he says. “A farmer is most receptive to change when the data and learning comes from his field, yet most are simply too busy to plan and execute small experiments on their farm,” he says.
Recker schedules his aerial imaging flights for early mornings. “Early mornings produce long shadows that show subtle differences in plant height, and those shorter plants usually signal an impact on yields,” he says. “But you won’t see that yield difference in a combine yield monitor or on a yield map, because they average the yield from a number of plants. You have to get down to the individual plant to really see what is making one plant different from its neighbor.”
Typically, straight-line patterns viewed from the air are manmade.
Recker makes it his business to help farmers figure out variability patterns that signal production problems and yield inconsistencies. “I hand-harvest the ears in a 17-foot, five-inch strip; that equates to 1/1,000 of an acre with 30-inch rows,” he says. “I usually run several replications, and lay the ears at the base of the plants.” The variation in ear size usually intrigues farmer-clients, he says. “Then they want to see the confirmation of what those ears look like on the ground to yields on paper.”
He weighs each ear, and measures plant-to-plant spacing. “I often see a 2:1 difference in yield from the best ear to the worst in the 17-foot span—it’s just amazing,” Recker says. Planter skips or plants that didn’t germinate and barren stalks are all yield killers. “I’ll take a double over a skip any day,” he says. “Plants adjacent to a skip compensate a little, but not a lot.
“I think there’s easily a 10- to 20-bushel an acre improvement there for most operators,” Recker says, “just by making better use of nutrients and seed in the space they have by understanding the variability in a field and being diligent in understanding the root causes of that variability and addressing that in the next season. It’s not something you fix this season, it’s a learning tool to get better next year.