Would you dare shoot for a 350-bu/acre corn yield? Francis Childs, Manchester, IA, did last year and didn't miss by much.
He was one of seven growers who topped 300 bu/acre in the 1997 National Corn Growers Association (NCGA) yield competition. But he was the only one who did it without irrigation.
Childs' entry measured 332.2 bu/acre. It was his first entry in the national contest, but wasn't his best. His entry in the conservation division of the Iowa Masters Corn Yield Contest went 344.2 bu/acre. Childs has won the Iowa contest seven times, including the past four years.
The top yield in the NCGA contest was posted in the irrigated no-till division by Bruce Ford, Hermiston, OR. He turned in an official yield of 334.1 bu/acre.
That's not bad for a farmer who grows corn as a sideline.
"Our primary crop is potatoes," Ford points out. "We manage the soil and rotation around the potato crop."
But don't believe that corn isn't important to Ford. He averaged 275 bu of 15%-moisture corn per acre on 900 acres in 1997. His winning entry came from a 30-acre field under a small pivot-irrigation system. It had been in wheat in 1996, potatoes in 1995.
Volunteer wheat in the field was grazed during the winter, then was killed with a Roundup burndown a week or so before planting.
Ford broadcast a dry fertilizer mix of 60 lbs of nitrogen and 150 lbs of potassium per acre before planting, then banded 50 lbs nitrogen and 180 lbs phosphorus in a liquid fertilizer at planting.
"All our fertilizer is based on soil and leaf-tissue tests," Ford reports. "We pull soil samples just ahead of planting. We take leaf petiole samples when corn is knee high and then a second soil sample at tasseling. We put on fertilizer in our irrigation water, so we can adjust rates each time we take new samples."
Once Ford turns on the irrigation, it runs all summer.
"We're in a semiarid area here, with only about six to seven inches of total annual precipitation. The soil is light sand, but we have plenty of water for irrigation. Our pivots make a circle about every 30 hours."
He planted the contest-winning field early, with a Deere vacuum planter equipped with Acra-Plant no-till V coulters to clear residue and then a straight coulter just ahead of the furrow openers.
His winning hybrid was Pioneer 3335, planted at about 40,000 seeds per acre. The stand at harvest was between 37,500 and 38,000 plants/acre.
"I manage my corn acres all the same, and I enter every field in the yield contest," says Ford. "Two years ago, I won the NCGA contest on a different field."
Back in Iowa, Childs says variations in the soils he farms precludes managing them all the same. Nevertheless, he insists that his contest yield last year was economical to produce.
"I have three 35-acre fields where I can really push corn yields, and I do manage them all the same," he says. "My costs on those three fields were about $610 an acre (including a land charge). I averaged more than 300 bushels per acre on those fields."
Childs planted Pioneer 34R06 for his NCGA entry. His Iowa Masters entry: Pioneer 34G81.
He has grown only corn on the three fields since 1966.
His land is deep-tilled with a mini-moldboard plow that runs 14-16" deep and lifts the soil but doesn't turn it over.
"It leaves all the residue on the surface," he says.
Before planting, he injected anhydrous ammonia at 400 lbs of nitrogen per acre. Knife spacing on his anhydrous toolbar is 10" rather than the usual 30" spacing for 30" rows. He also put on 3 quarts of Bicep Lite preplant and a pint of Buctril postemergence.
He planted his contest corn May 8.
"That's not as early as I would have liked, but it worked for me this time," he says.
He applied 150 lbs/acre of a 4-10-10 starter with the planter.
"These soils already test very high in P and K, so we put on no additional fertilizer."
The planting rate was 45,000 seeds/acre, and his stand count at harvest was 42,000.
Because he grows continuous corn, he always uses rootworm insecticide. His choice last year was Counter Lock-N-Load.
"Corn borer pressure was light last year," he adds. "That's one reason the yield went as high as it did."
Like Ford, Childs believes in frequent testing to make sure his corn isn't hungry.
"We run a leaf tissue analysis when the corn is about three feet tall. If this shows we're running short of nitrogen, we sidedress. But in 1997, we didn't need additional nitrogen."
On most of his farm, Childs uses 200-240 lbs of nitrogen per acre, with a yield goal of around 200 bu/acre. He checked yields 38 times in 1997 by weighing measured strips. The average yield was 253 bu/acre.
"Not bad for a CSR (corn suitability rating) of just 74," says Childs.