Why is it that farmers competing in state and national soybean yield contests routinely grow 60 or even 85 bu. per acre yields when the national average is closer to 44?
That’s the question that motivated some ground-breaking research by Fred Below, a crop physiologist at the University of Illinois. The wise-cracking, caffeinated professor presented his top-line results to a standing-room-only audience of farmers at last week’s 2013 Commodity Classic.
There’s a lot more at stake in the answer to this question than a simple scientific inquiry. To feed an extra 2 billion mouths over the next 40 years, "we need to double the production of all grains," says Below. But at current rates of productivity gains, it will take 100 years to reach 85 bu. per acre.
"Fortunately, there’s a lot of low-hanging fruit," says Below. In fact, nearly every tactic Below tried – whether it was adding more nitrogen or planting in denser rows – improved yields. The best course of action, he says, is "intelligent intensification," academic-speak for putting more of the right stuff in the ground at the right time.
Before diving into his secrets, Below listed some "pre-requisites." He assumes that farmers are draining their fields properly, that they engage in early weed control – "no matter how satisfying it may be to let them grow then go out in the field and kill them with glyphosate" – and are maintaining proper pH levels for soils.
Here’s a rundown on the six "secrets" Below revealed, one at a time.
Because he figures everyone could guess weather was among the secrets, he lists it first. But it may belong at the top, since according to his studies it has a greater influence on yields than anything else. That’s unfortunate because it can’t be controlled.
Fluctuating weather conditions in Below’s home state of Illinois have resulted deviations from trend-line yields of 0.7 bu. per acre over the past 20 years.
Good weather, of course, influences early planting, which can create opportunities for early vegetative growth and node formation. "I think we need to plant earlier, but it’s the weather that determines the planting date," Below says.
Even if you plant early, the professor says, you need to plant the right seed and protect it. The impact of heat and drought can be mitigated by management practices that promote strong root development, such as fertility, enhanced seed emergence, and disease control. Ethylene blocking compounds that alleviate corn stress may work on soybeans as well, he adds.
But there’s nothing like a good rain in August. That’s what saved Below’s test crops last year. "When any of my agronomic schemes don’t work," he says, "I just blame the weather, and I’m usually right."