Row spacing is a major consideration for farmers to attempt consistently producing 300 bushel-per-acre corn yields, noted Fred Below, Ph.D., University of Illinois, plant physiologist, in small-group discussions following his repeated explanation of “The Seven Wonders of High-Yield Corn Production.” Below made his presentations at the Farm Progress Show in Decatur, Ill., last week.

Demonstration corn plots were planted in conjunction with Mosaic fertilizer company, Agrotain stabilized urea company, BASF crop protection company and Dekalb seed company. The demonstration plots were not planted to yield 300 bushels but to compare typical corn production with Below’s high-population, high-management, and high-fertility system.

The illustration high-population plots were planted to have 45,000 plants per acre in 30-inch row spacing as compared to a typical 32,000 plants per acre.

Below sees 20-inch rows for high-population plots being the logical planting for the future.  He believes in 20-inch rows compared to 30-inch rows because a grower is “going to be able to put more plants in an area with less plant-to-plant competition.”

If someone says they harvested 300 bushels from planting 32,000 plants per acre, “that is a fish story. There is no way it can happen. Every ear would have to have 1,200 kernels or something like that.”

The logical question about the potential of twin-row planted corn came from those listening to Below. 

At one point he thought twins might be the way to go in his early investigations of how to consistently grow 300 bushel per acre corn.

He said “I’ve seen some twin rows in North Dakota that were the best thing you’ve ever seen, but not here (central Illinois).  If you are going to plant twins here, you better have the right hybrids. It is all about the right hybrids that will tolerate high temperatures; otherwise, you are not going to get the full advantage of the twin-row high populations”

Below explained that the close proximity of corn plants in twin rows results in four degree higher temperatures in the leaf mass, which is not conducive to high yields.

He said, “Twin rows are going to be really important if you have cool temperatures. If we get stuck in a cold year, we want that extra heat that a twin row gives us. Otherwise, in a hot year, it won’t pay off.”

Below said using irrigation with twin rows is like altering the weather, and there is good potential in some situations, but he also noted that a fungicide definitely will be needed because of the heat and moisture that encourages disease.

In North Dakota, they have long days and short season. “They have got to get light as quickly as possible. We have shorter days and longer seasons. It is not as important to us (Iowa, Illinois, Indiana). But think about planting late and if you plant late, you want more plants out there quickly getting that light. I think we need to do some of the things they are doing up north to get more light to each plant.