Sidedressing nitrogen for corn is more economical, more efficient and more environmentally sound than applying all N inthe fall or as a preplant, according to the experts.
"When you sidedress, you apply the N as needed, depending on the crop condition, stand, weather and prices," says Steve Wiedman, an agronomist with Mowers Soil-Testing Plus, Toulon, IL. "And there is little N left in the fall to leach during the winter."
Mark Flock, agronomist with Brookside Labs, New Knoxville, OH, is another sidedress advocate.
"I like to see a little preplant N, followed by a soil nitrate test when the corn is up," he says. "You can sidedress as much N as the crop actually needs, and when it needs it the most."
Flock cautions, however, that it requires an experienced fertility adviser to interpret the soil N test and determine how much N to sidedress.
Dan Towery of the Conservation Technology Information Center, West Lafayette, IN, points out that a White House task force on hypoxia is seeking a 20% reduction in nitrogen loss. More sidedressing would help achieve that goal, says Towery.
Despite the many advantages of sidedressing, most farmers are not doing it. The biggest limitations are fear that wet soils will prevent timely application and the possibility of crop damage, says Wiedman.
But Paul Finley is convinced the benefits of sidedressing far outweigh the limitations. This Earlville, IL, grower has sidedressed all his 600-700 acres of corn for the past 10 years.
"We've never had a year that we didn't get the sidedressing done," he reports. "With sidedressing we don't lose N as often happens with fall or preplant application.
"We apply less total N by sidedressing and often pay $15-20/ton less for it at that time of year," Finley adds. "Plus, we don't have the $7/acre cost of N-Serve that goes with fall application. All-in-all, we save $10-11/acre by sidedressing, with no loss of yield."
The Law brothers, Richard, John and Don, also sidedress a sizable corn acreage near Atlanta, IN.
"We used to apply our nitrogen preplant," says Richard Law. "But we now use that time to spray early and plant earlier.
"To make certain we get the sidedressing done, we rent an applicator to go with our own. We've always gotten the sidedressing completed, although the corn was relatively tall in a couple of the years."
Law points out that sidedressing also delivers a bonus - it serves as a form of cultivation.