Roger Wenning is planting at 45,000 seeds per acre in twin rows in test plots, and plants at 39,000 as a standard rate. He farms in southeast Decatur County on what some think are marginal soils. He averaged more than 200 bushels per acre this year.
The trend toward higher populations and different row spacing to accommodate those increased populations is definitely real. Stine Seed Company is testing hybrids at 55,000 plants per acre in 12-inch rows in a big way. Seed reps for Stine want customers to see that with modern genetics, some hybrids can handle higher populations, while others still can't handle them as well. Calmer Corn Heads has introduced a large, 12-inch row corn head. The tendency is toward narrower rows, thicker stands.
Does that mean you should kick up seeding rates for 2014? Should you go from 32,000 to 40,000 plants per acre, just like that? Darrell Shemwell, an agronomist with the Posey County Co-op in southwest Indiana, says there are several factors to consider before making such a drastic change.
"The first is whether you have good enough soils to support 40,000 plants per acre and high enough nutrient levels for it," he says. The agronomist suggests looking at variable rate planting with prescriptions tailored to each field if you're serious about increased planting rates.
Shemwell agrees that if you're going to seeding rates of 40,000, you ought to consider 20 inch rows or twin rows. Making that change brings another set of hurdles – how to sidedress if you want to, how to apply chemicals and how to harvest.
"Increase your planting population to a level that your soils will sustain," Shemwell says. The Indiana Certified Crops Adviser adds, "We have seen in some of our hybrid population trials that the ear size of some hybrids isn't that much different at 40,000 compared to 30,000. More plants per acre, more ears per acre equals higher yield."