Anyone who grows corn has likely heard that if hail or some other calamity affects young corn, whether it regrows depends on if the growing point was left intact. If the growing point was either below ground or not damaged, plants have a good chance at regrowing and behaving normally.

Dave Nanda decided to illustrate what that looks like so you can visualize it instead of just reading about it. Nanda is an independent crop consultant based in Indianapolis and scouts the Corn Watch ’18 field regularly. Corn Watch ’18 is sponsored by Seed Genetics-Direct, Washington Court House, Ohio.

In early June, when corn was at about the seven-leaf collar stage, or V7, Nanda set up a simple demonstration and repeated it in a second location. With a knife, he cut off plants at three heights: just above ground level, about 3 inches above the ground and about 6 inches above the ground. In each case, he completely removed the upper part of the plant.

“The growing point comes above ground around the V5 to V6 stage,” Nanda says. “We sacrificed another plant to determine that it was definitely above the ground, about 2 to 3 inches above the soil line.”

Definite impact
As expected, the plants Nanda cut just above ground level were destroyed. Three weeks later, there were only dead stubs. “That was extreme, but I wanted to prove the point,” he says. “If the growing point is completely destroyed, the plant can’t grow back. It’s done.”

The plants he cut at about 3 inches above the ground, likely nipping the growing point, were trying to still grow. In each case the resulting plant was about half the height of normal neighbors and light green in color. Lower leaves showed signs of being cut.

The kicker was plants cut about 6 inches above the ground, clearly above the growing point. Since the growing point wasn’t injured, those plants continued growing. They were only slightly behind neighboring normal plants, which were tasseled out and beginning to shoot silks. The injured plants with intact growing points were sending out tassels.

Recovery process
What made these plants easy to spot since they were nearly as tall as their neighbors and had the same dark-green color? The first several leaves above the soil surface were stubby, consisting of half a leaf or less.

“When we cut through those plants, we apparently cut off future leaves which were still wrapped in the whorl,” Nanda explains.

He says leaves that will emerge later are gathered inside the whorl even when the growing point in the center of the stalk is several inches below the whorl. Future leaves grow around the growing point. When the plants were cut off, those leaves were severed. But since the growing point was intact, the plants continued growing, and leaves that were cut eventually unfurled. Leaves that came out later near the top of the plant were normal.

“Those plants will likely still produce a decent ear,” Nanda says. “They may not be as productive as their neighbors, but they’ll produce corn.”

Nanda will follow development of these plants all the way to harvest. Watch for future updates.