The brace roots on one of two hybrids in the field Dave Nanda was scouting were impressive. He found a point where the two hybrids were next to each other so he could compare size of brace roots. There was a visual difference.

Does that mean the hybrid with the larger brace roots will yield more corn this year? No, says Nanda, an independent crops consultant based in Indianapolis.

You don’t harvest roots, Nanda quips. You harvest grain. And just because one hybrid has larger brace roots gives no indication as to whether it will yield more corn. There are many other characteristics you need to consider and compare, he says.

“What it does mean is that the plants with the bigger brace roots are likely well-anchored in the soil,” he says. Big brace roots are a positive characteristic. If they extend into the soil, they can even help take up moisture during dry parts of the season.

Good rooting is one factor that should help keep corn upright, especially as stalks begin to lose their integrity before harvest, he notes. As you scout fields or pay attention while combining, it’s definitely a factor worth recording and noting.

Will it be the characteristic that causes you to decide to plant that hybrid again next year? By itself, that’s not likely. You need to know more about the total package of characteristics, Nanda says.

Other factors
Some hybrids are more resistant to diseases than others. In this case, the hybrid that had bigger brace roots also showed less evidence of gray leaf spot later in the season. That can be important, and not just because of loss of leaf tissue that catches sunlight, Nanda says. If a plant is susceptible to leaf diseases, it may also be set up for stalk diseases as the crop dries down. That can result in lodging.

On the flip side, the hybrid with smaller roots had a girthier ear, with an average of 18 rows of kernels around the ear. The hybrid with bigger brace roots tended to produce ears with 16 rows of kernels.

When Nanda broke ears in half, he found that the girthier ear had a bigger cob. Kernels were well-formed but not overly deep. The hybrid with the narrower ear and fewer rows tended to have flatter, deeper kernels.   

“It’s difficult to tell how those factors will play out in terms of yield,” Nanda says. “Two extra rows of kernels per ear is a big deal. It would take heavier kernels on the other hybrid or longer ears with more kernels per row to make up for it.”