The prolonged 2009 fall harvest continues to be felt into the new year, as producers shift the “normal” fall fieldwork into the spring. And that could create a time crunch. Corn & Soybean Digest asked Extension experts for pointers:
I DIDN'T GET MY FALL TILLAGE DONE, SO HOW DO I PREP FIELDS THIS SPRING?
“Farmers will most likely not have the time to do that tillage in the spring, given the time window and soil conditions,” says Mahdi Al-Kaisi, Extension soil management specialist at Iowa State University (ISU).
If you're planting soybeans following corn, you should be fine with planting into corn residue as no-till, he says. “Our research for the past seven-plus years across the state with various tillage systems shows no significant difference in soybean yield among all tillage systems,” Al-Kaisi says.
If you're planning on corn following soybeans or corn, recommendations will vary depending on soil type. “The most challenging will be the poorly drained soils where tillage helps warm up the soil,” Al-Kaisi says. “Alternatives to consider include residue cleaner attachments on the planter set aggressively to help remove residue and create significant soil disturbance to help warm the soil bed and early seed germination.”
Choices are limited, but remember that removing the residue from the planting zone is as effective as plowing the field.
“Depending on soil moisture conditions in the spring, light tillage or field cultivation can be as effective as deep tillage where the potential for soil compaction and sidewall compaction can be damaging to yield,” Al-Kaisi says. “That is especially true if the soil is at field capacity or wetter, which will most likely be the case in the spring.”
And no matter how rushed, stay off wet soils. “Wet soils have much less bearing strength and are more easily compacted,” says Richard Wolkowski, Extension soil scientist at the University of Wisconsin. “Working the ground when it's too wet will lead to future management problems and yield loss. Even waiting a day to allow the soil to dry will increase the soil-bearing strength.”
I DIDN'T GET ALL MY FALL NITROGEN APPLIED. NOW WHAT?
For producers who did not apply their normal amounts of anhydrous ammonia, there's a good chance that a considerable amount of N needs will be applied this spring as a preplant or sidedressed.
“It gets tougher on spring fieldwork when more than the usual amount of fertilizer N needs to be applied in the spring,” says John Sawyer, ISU Extension agronomist. “But there are opportunities to get that accomplished, and over a wide time window.”
If producers want to apply in the very early spring, then a form like anhydrous ammonia that nitrifies more slowly, or a slow-release material like coated urea would be preferable. “If you are going to switch to a product like urea or urea-containing like UAN (urea ammonium nitrate solution, 28% or 32%), then incorporation is important to limit volatilization. Or use a urease inhibitor if you are going to surface apply and not incorporate,” Sawyer says. “For nitrate-containing fertilizer, like UAN or ammonium nitrate, application close to planting or injection (UAN) after planting is preferable to early spring application.”
Sawyer says that there could be some room for switching from a product used normally, “but the fertilizer supply system cannot provide for large product switching on a short notice. It's also helpful for producers to use products they are familiar with, especially if the spring season gets rushed.”