Cornfields are “dying down” along Interstate 80 through Illinois and Iowa — with some exceptions. Those which are still a vibrant green from base leaves to tassel are typically fields fed late-season nitrogen.
One of the more effective ways to feed substantial amounts of 28% or 32% nitrogen is the “Y-Drop” setup: A ground sprayer fitted with Y-shaped delivery tubes trickles the liquid right at the base of stalks. You set the sprayer boom so the ‘shoe’ skims at ground level and the trailing pipes each deliver a uniform stream to the row.
Of course, the Y-Drop rig depends on good-standing corn well into the season. But with precision GPS systems and straight rows, placement should be quite fast and smooth.
Hal Brown of Mulberry, IN sent us the photos below of field trials showing that 50 units of nitrogen as 28% applied 2×2 with the planter, plus 150 units with Y-Drops, out yielded — by more than 50 bushels — 200 units of NH3 applied before planting.
The aerial photo of the field below was shot from a screen presentation at a field day, so it’s fuzzy. But you can see that corn fed with 50 units from the planter, then followed with 150 units via Y-Drop at six leaves, yielded 184 bushels. The same total nitrogen delivery pushed corn to 205 bu. when the Y-Drop application was delayed until the 12-leaf stage. That’s when nitrogen demand really kicks in. Placing the N near the primary root mass makes a high percentage of it available.
A similar field trial showed that Y-Drop application was more effective than 28% nitrogen injection behind a coulter.
Such results may vary depending on the season. But with all the early rain this season, and then dry weather later in the eastern Corn Belt, “spoon-feeding” nitrogen was a winner.
Our favorite fertility regime for corn is a little N and other nutrients and biologicals in-furrow with the planter, plus nitrogen and other nutrients 2×2 with the planter. A Nebraska farmer, Arlynn Aldinger, proved to us several years ago that about 3 ounces of WakeUP per acre, blended with the in-furrow mix, can add 3 to 6 bushels to the boost that the nutrients alone will give.
After nutrients applied with the planter, we tissue test and foliar feed trace elements. Often we also foliar apply a couple of gallons of Kugler 2075 to give corn a nitrogen and potassium boost. We’ve also dribbled on straight 28% late in the season with our Hagie.
So far we don’t have Y-Drops… but that looks tempting!
Hal Brown notes that one of the original designers/users of the Y-Drop concept is Keith Schlapkohl of Stockton, IA, in 2007. He still uses his heavy-duty version, with stable Y tubes, on his Walker high-clearance spray rig. He worked with designer/builder Dan Muff of Ventura, IA. Dan went on to commercialize the concept.
As of Sept. 10, Keith reports that most of the remaining live GMO corn and soybean fields around him, and those eastward into Illinois, abruptly died and turned brown Sept. 6-9.
Posted Sept. 8, 2015 Updated Sept. 10