You are here

4 steps for better corn-on-corn

Robert Jones and his family have significant hurdles to face in growing continuous corn near Palmyra, Indiana.

Prior to their farming them, some of the Joneses’ fields were continuously cropped to soybeans since farm foreclosures in the 1930s. They are still dealing with the erosion fallout.

“On some of those farms, we’re dealing with subsoil, not topsoil,” says Robert.

Soil organic matter levels in their fields are on the low side, ranging from 1.9% and 2.9%. Soils with low soil organic matter levels tend to dry out quicker and don’t contain as many natural nutrients as those on the higher end.

Still, they’ve adapted to these challenges through a sound strategy we’ll outline in our February issue. Until then, here are some other steps they follow in growing corn-on-corn.

1. Early-Season Fungicides

Hybrid selection is one of the ways they manage disease. Early-season fungicides applied at the V5 stage (five fully exposed leaf collars) are another method. They can also combine fungicide applications with postemergence liquid herbicide and fertilizer applications. Overall, Jones credits the early-season fungicide application with boosting yields an average 7 bushels per acre.

They do not apply fungicides at tasseling due to the geography of their fields. “It is difficult to get an airplane to apply fungicide accurately enough on small fields,” he says.

2. Early-Season Pest Control

The Joneses key emergence and early-season stands by a seed treatment that fends off nematodes and early-season insects and fungal diseases. Jones says one reason populations of corn nematodes-- native to North America -- have grown is due to corn rootworm-resistant traits. That caused Jones to discontinue using Counter, a soil-applied insecticide that controlled both corn rootworm and nematodes.

“We found some spots that just didn’t grow (corn),” he says. “Our agronomist advised sending soil samples to an independent lab. We finally narrowed it down to corn nematode. We found the nematodes we had to be Lance, one of the most prolific ones.”

The nematicide-treated seed nixes nematodes. Capture, an in-furrow insecticide also reinforces insecticide-treated seed in combating grubs and black cutworm.

3. Harvest and Storage Adjustments

The Joneses used to rotate soybeans with corn. “We couldn’t break the 60-bushel (per acre) yield barrier for soybeans consistently,” he says.

That’s why they shifted to corn-on-corn. The switch came with a perk.

“Continuous corn is easier to manage logistically,” says Jones. “It was hard to manage two combines and two combine crews. “We’d always wonder, 'Should we switch to corn today?’” Jones says. “Then the soybean crew would be short of help.”

No longer. The Joneses downsized from two combines to a larger one. They run a class 9 16-row combine equipped with a Drago head.

Jones notes differences exist between combines in terms of corn left behind. Some models leave a trail of knee-high volunteer corn behind going into winter. He’s satisfied with the setup he has now, as it meets the goal of limiting corn harvest losses to less than 1 bushel per acre.

“If the crop is standing reasonably well, that’s obtainable,” says Mark Hanna, Iowa State University Extension agricultural engineer.

The Joneses bulked up on storage after shifting to corn-on-corn by boosting their storage by 200,000 bushels in 2004.

“In a normal year, we didn’t have enough storage,” he says. A Meyer tower dryer enables them to keep harvest going with no storage bottlenecks.

4. Dabble With Twin Rows

The Joneses plant most corn in 30-inch rows. They have dabbled with twin-rows by tweaking a Kinze 3650 planter to plant twin rows spaced 7.5 inches apart. Twin-row population ranges from 30,000 to 36,000 plants per acre.

So far, results have been mixed. In some fields, yield differences between spacings have been nil. Other times, twin rows have edged 30-inch rows by 7 bushels per acre, as they did in 2011.

“It may be different in a wet year,” says Jones.

Read more about