Many seedsmen and farmers alike are telling us they are not backing off on corn seeding rates for 2016 just to save money on seed. Yet some agronomists say the opportunity is there if you want to trim costs. They point to data that indicate that you may not take that big of a yield hit for doing so.

Tom Stein, and Indiana Certified Crop Adviser and manager of Boswell and Templeton Ceres Solutions branches in Indiana, was recently asked to address this farmer’s situation.

DROP SEEDING RATE, OR STAND FIRM?- Many farmers say they’re holding firm on seeding rates, although some research indicates they could cut back to optimize net income per acre.

I’ve been planting 33,000 seeds per acre. After reading articles about a fairly flat yield curve for population in this range, I may back off to 29,000 as a seeding rate to save money. Is that reasonable? I have average to good soils. Am I taking more risk by cutting back to that level?

Here is Stein’s response. Remember he is just one agronomist. Others may have different opinions.

“Seeding rates for corn have increased readily over the past several years in an attempt to take advantage of genetic improvements in stress tolerance of newer corn hybrids to achieve maximum yield potential. The desire to reduce your seeding rate from 33,000 seeds per acre to 29,000 seeds per acre is not unreasonable, and there is research to support that decision.

Agronomic vs. economic

If growing conditions are good and you have the soil to support it, higher plant populations offer the potential for the best yields. However, the optimum agronomic seeding rate is different than the optimum economic seeding rate. The optimum agronomic seeding rate results in maximum yield regardless of cost. The optimum economic seeding rate is the seeding rate that generates the most income when yield, seed cost and grain price are factored in.

In an attempt to evaluate yield response to plant population, Purdue University researchers, primarily Bob Nielsen and Jim Camberato, conducted 67 field scale trials with growers across Indiana since 2008. Those findings showed that the maximum agronomic seeding rate for corn under normal growing conditions was 34,000 seeds per acre, which resulted in a final population of 32,000 plants per acre.

However, the optimum economic seeding rate for $3.50 per bushel corn and a seed cost of $275 per 80,000 kernels, was 28,800 seeds per acre. That is right within the range of your plan.”