'Knee-high by Fourth of July'? Not anymore

"Knee high by the Fourth of July" used to be a common saying that helped people gauge how the corn crop was doing, but these days it's a poor corn crop that isn't way past that point.

On the day before the holiday this week, southern Minnesota farmer Rachel Hollerich repeated the well-known words while standing in corn nearly 6 feet high - taller than she is.

There's no clear explanation when, where or why the phrase started. But even with its uncertain origins, it sticks around as a simple rhyme that people love to say.

Hollerich, who runs the organic farm Good Earth Mill and Grains with her husband Trent, said the phase doesn't mean what it did decades ago.

"Knee high? Well, it's supposed to be probably chest high by the Fourth of July," Hollerich said. "And if it's knee high, you're not sitting very good anymore."

The phrase has become outdated because plant breeders have improved corn genetics after more than a century of cross-breeding.

Forrest Troyer, an adjunct professor of crop sciences at the University of Illinois, said corn is now much more stress-tolerant.

Modern corn can flourish in conditions that might have stunted the plant in past generations. That means it doesn't matter whether it's dry, or wet, or hot, or cold. The stalk generally keeps growing and produces an ear.

Troyer said that toughness is one reason farmers can plant earlier each spring, often in less than ideal conditions. At 83, he can still remember something he heard as a boy that demonstrates the change.

"My uncle said a long time ago that if he only had one day to plant corn he'd plant it on May the 20th," Troyer said. "Well, my gosh, now we're planting in mid-April."

Earlier planting means more time to grow. Crop reports show the average height of Minnesota corn was a little more than 4 feet on July 1.

Some of the best fields are along the Iowa border, where Jackson-area farmer Kent Ringkob looks at corn that's at least a foot taller than he is.

"This corn got a little stretching left to do but it's probably at a good seven feet already, and will probably make about eight," Ringkob said.

Some of his corn is already tasseling and putting on ears. He said that's a little unusual, but corn that is chest- to head-high on the Fourth of July is not. He has the photos to prove it.

"Our family's taken a picture of the corn on the Fourth of July I'd say since late 30s or early 40s," Ringkob said. Even back then, the corn sometimes passed knee height.

Though the average height has increased steadily through the years, Ringkob still likes the knee-high line.

"Suppose it's got a nice rhyme to it, doesn't it?" Ringkob asked.