Purdue's Tony Vyn, an Extension Agronomist, coined an interesting term earlier this month - "revenge tillage" - and he's concerned farmers will want to just hit the field in disappointment over yields and other factors. His caution: "I don't want farmers to overestimate the need for fall tillage just because of the 2012 drought and poor crops. It's important to adopt a tillage system that leaves topsoil uniformly in place to build up a whole field's resiliency in root-zone water retention over time."
With light crops, you may not have the same residue issues you normally do, which means fall tillage could bring on the threat of erosion and other issues just because you stick to what you've always done. Of course, he notes the benefits of no-till and how the reduced soil disturbance with that practice can mean less evaporation loss and higher soil water availability to roots. Yet no-till didn't offer the protection against drought as expected.
In the release from Purdue that details Vyn's tillage concerns, the university notes that early high temperatures and lack of rain limited both root growth and shoot growth this year. "The near-surface soil was so dry, lack of tillage meant more resistance to root penetration, meaning corn and soybean plants in those fields sometimes experienced more drought stress before flowering than other tilled fields, despite the crop residue cover," Vyn says.
He adds that those same conditions may never happen again and a "later-season drought occurring after deep early root establishment would have favored no-till more."
He advocates looking at your tillage needs and choose from several management techniques including disk, chisel plow, deep ripper, moldboard plow and strip tiller. The winner in that list for Vyn: strip tillage.
"It's a proven, versatile tillage practice that creates a warmer, drier zone of soil in the spring that ensures timely seed placement in both corn-soybean and corn-corn rotations. Precision automatic guidance systems have also simplified crop row placement in the center of the loosened strips," he says.
You've got time to choose your fall tillage method. A little scouting of just what residue you have will be important. And if you experience fall rains (saints be praised!) you may not want to rush fall tillage. Hitting wet fields can damage soil structure more than necessary.
So consider avoiding "revenge" tillage.
Of course that phrase, "revenge tillage" is pretty cool. I wondered about some other phrases that could eventually become popular, like "sniper spraying" or "power planting" but for now, I'll leave the new phrases to the experts. Thanks Dr. Vyn.