Will Power, winner of the 2018 Indianapolis 500, and Ed Carpenter, the pole-sitter and second-place finisher, have nothing on corn this year. Their cars may have been fast, but corn growth was just as fast.
“I’ve never seen corn get out of the ground and grow as fast as it did in the Corn Watch ’18 field,” says Dave Nanda, a crop consultant based in Indianapolis who helps monitor progress of the Corn Watch field. The project is sponsored by Seed Genetics-Direct, Washington Court House, Ohio.
Seeing that Nanda has worked with corn for roughly 60 years, that’s saying quite a bit. He credits the heat that accumulated as growing degree days and ample moisture at the Corn Watch ’18 location with the fast growth pattern.
Two different corn hybrids were planted April 30. When Nanda inspected the field May 25, plants of both hybrids were at the five-leaf stage, with five leaf collars exposed. They were pushing hard on the sixth leaf, he says. When Nanda sliced open plants, the growing point was just ready to emerge. “That’s incredible growth for corn which hadn’t even been in the ground four weeks, especially when it was planted the last day of April,” he says.,
Indianapolis blew away the old record for number of days at 80 degrees F or above in May. Some days near the end of the month topped 90 degrees F. Nights during the last half of the month were relatively warm. The GDD formula projecting growth tops out at 86 degrees F, but GDDs still accumulate quickly when it reaches that mark most days and doesn’t drop below 60 degrees F very often at night.
Leaf chlorosis theory
Nanda says the Corn Watch ’18 field isn’t the prettiest field of corn he’s seen. A strong storm with high winds and some hail whipped through the area four days before he inspected the field, tattering leaves and causing some plants to curl their leaves.
“There is no control plot, so we won’t know if it hurts yield,” Nanda says. “Anything like that slows up the plant, but it likely won’t cause much harm in the long run. The growing point was still underground when the storm hit.”
The other factor detracting from looks a bit is some light-green to yellow marks up and down some of the bigger leaves on many plants. Both hybrids display this same appearance. Nitrogen was applied a few days before planting, and the operator wonders if that played a role. However, Nanda doesn’t think that is the most plausible theory.
“When you first looked at it, you though they were corn borer shot holes, but in most cases, there were no holes,” Nanda says. It wasn’t corn borer. “My best guess is that the plants were growing so fast that as plants unwrapped out of the whorl, some tissue turned a bit yellow for a short time. If it happened unwrapping out of the whorl, it would explain the shot-hole appearance. I don’t expect any long-term effect.”