Dave Nanda found a stalk on the outside row of a cornfield that typifies what corn yield potential could be someday. The stalk had one huge ear and a second good-size ear. Using the yield estimation formula, if you had 32,000 stalks like that per acre, you would harvest over 580 bushels of corn.
“Twenty-five years ago, I thought perhaps the ceiling for corn yield was 500 bushels per acre,” Nanda says. “Farmers have already proven that too low, with a recorded yield of over 600 bushels per acre a couple years ago. Finding this stalk and calculating yield based on it is another reminder that we don’t get close to reaching corn yield potential, even with today’s modern hybrids.”
Nanda is director of genetics for Seed Genetics Direct and a veteran corn breeder. Here are five challenges to overcome if you want to find stalks like the one pictured, and yields approaching 600 bushels per acre, in your fields:
1. Light. One reason this stalk performed so well was that it was on an outside row, Nanda says. Enterprising farmers and agronomists have tinkered with strip-row corn and soybean rotations for over 40 years, and still are, because they know that an outside row receives more light. The challenge is twofold: figuring out how to make rows 2 through 5 in a six-row alternating strip or rows 2 through 11 in 12-row strips act like the outside row, and keeping soybean yields from decreasing due to shading in the strips that aren’t corn.
2. Space. Each plant needs enough room to know early on that it can produce freely without undue competition from neighbors. This stalk had more room next to it than it would have in 30-inch rows at 32,000 plants per acre. Expect the search for the right row spacing and plant population per acre to produce higher yields. Don’t be surprised if the solution is something other than 30-inch rows.
3. Height. Farmers once took pride in how tall they could grow corn. There are indications that the future could be about growing much shorter corn. Some believe it would do a better job of letting light into lower leaves and could withstand higher populations.
“The plant of the future I envisioned 25 years ago was Christmas-tree-shaped so more light could propel photosynthesis on lower leaves,” Nanda says.
4. Moisture control. The plant pictured here fared relatively well, even though it was dry during grain fill. Using tile to take away too much water in the spring, and perhaps using irrigation or a combination of drainage and irrigation with water collected into a holding pond in the spring, might lead to more consistent moisture conditions all year, every year. Some believe irrigating with tile drainage water is not as far-fetched as it sounds.
5. Nutrient levels. The plant in the picture didn’t run out of nitrogen, but many plants in multiple fields — and even inside this field, where early-season nitrogen losses due to wet conditions occurred — did run out of nitrogen. The result was a big hit on yields.
“We need to utilize sidedressing and other available technologies to make sure corn has enough nitrogen when it needs it,” Nanda says.