First applying nitrogen late in the season with a high-clearance sprayer was thought to be reserved for situations where wet soils denitrified too much N. They were rescue operations. Now some people are wondering if adding N later, before tasseling, will pay for itself and boost yields. This would be part of a spoon feeding program, not a rescue operation.
A survey of nearly 70 Indiana Master Farmers shows that so far, the practice isn't catching fire nearly as quickly as many other new technologies. Just under one in 10 in the survey said they use a high-clearance spray rig to apply N later in the season.
One reason is physical capability. Not all sprayers have enough clearance to apply N that late in the season. If you don't have a sprayer with that much clearance, then you may have to have the N custom applied by a dealer or someone with a high-clearance rig.
Beck's Hybrids in their Practical Farm research is not only studying if late season application pays, but which method of applying it works best.
In tests near Downs, Ill., at their central Illinois Practical Farm Research Plot, the top treatment netted nearly $50 per acre over applying all of the N at sidedress. The same amount of nitrogen was applied on each plot. It was a matter of timing and placement, not amount of nitrogen.
The Miller sprayer with high-injection system produced the highest dollar advantage this year. The Hagie system with knife injection also produced nearly a $30 per acre increase. Both of these are high-clearance sprayers that can be equipped with injection equipment to run in front of the sprayer.
Using Y-drops and leaving N on the surface was about equal to injecting the N at the V 4 leaf stage. Dribbling on n late season vs injection at V4 actually produced a loss of about $60.
Becks' report says they will continue to look at this, believing there may be a future for late-season, high-clearance applications, particularly if injected into the soil.