Hot topics: Variable corn seeding rate and Farm Bill

Tony Nye - OSU Extension

Despite the continued roller coaster of weather, I continue to see a lot of farm activity throughout the county which would include spraying, applying nitrogen and other nutrients to fields, tillage work, tile repair and even some limited planting is occurring.

One hot topic for discussion the past few years has been around the idea of variable seeding rates in corn production. Does this production practice have value for today’s corn producer?

Finding the best seeding rate is important for efficient corn production, but the “optimum” seeding rate with profitability in mind, can vary within and among fields with small differences in soils and weather.

While adoption of variable rate technology is increasing, there are still questions related to how this technology will affect seeding rates, profitability, and be impacted by yield level compared to using a uniform (or fixed) seeding rate with modern hybrids.

In order to help estimate the profitability of variable rate corn seeding, University agronomy specialists from Ohio State University and the University of Illinois used results of seeding rate trials in Ohio (93 trials) and Illinois (32 trials) to see how variable the response to seeding rates was, and to see if factors like yield level might help us do a better job of setting plant populations.

According to the work, in Ohio, 80 percent of the environments showed a quadratic yield response to seeding rate, meaning that most yields were lower at the highest seeding rates compared to medium seeding rates.

The economic optimum seeding rate (EOSR, or seeding rate resulting in the greatest profit) was calculated for each trial assuming a seed cost of $3.00/thousand seeds and grain price of $3.75/bushel. The EOSR ranged from 18,000 to 44,340 seeds/acre, with an overall average of 32,129 seeds/acre.

Yield at the EOSR ranged from 117 to 271 bu/acre (205.5 bu/acre average), which resulted in a return-to-seed (RTS) range of $360 to $900/acre with an average RTS of $673.52/acre. The uniform optimum seeding rate (UOSR) that maximized profitability was 32,721 seeds/acre and 202.6 bu/acre, respectively, with an estimated RTS of $661/acre.

Overall, the estimated RTS advantage from using the EOSR in each trial was $12.53/acre. There was a weak relationship suggesting an increased EOSR with increasing grain yield, but difficulty still exists to pinpoint the best seeding rate to use before the season starts.


There is potential for modest increases in profitability from optimization of corn seeding rate in environments with a range in yield levels.

Predictions of optimal seeding rates within a field and year will need to improve beyond current levels before estimated RTS of this level will be approached.

Small changes in seeding rates may be needed to impact profitability, but obtaining this resolution on small spatial scales is a challenge that will need to be addressed in future research.

A full fact sheet summarizing results of this analysis can be found here: AGF-520 Estimating Return-to-Seed of Variable vs. Uniform Corn Seeding Rates (

Farm Bill

As we all know by now, the 2018 Farm Bill, passed by Congress and signed by President Trump, now awaits implementation by United States Department of Agriculture (USDA), agencies like the Farm Service Agency, Natural Resources Conservation Services, Risk Management Agency and many others.

The passage of the farm bill authorizes funding for many of the federal programs producers utilize throughout the growing season. This bill is considered to be mostly evolutionary not revolutionary, but there are still changes that will be important to producers and agribusinesses.

Last week, The Ohio State University, the Purdue Center for Commercial Agriculture, the University of Kentucky and Farm Credit Mid-America hosted a Farm Bill Summit at the Versailles High School in Versailles, Ohio.

The program featured presentations by three of the nation’s top ag policy professionals: Keith Coble from Mississippi State; Jonathan Coppess from the University of Illinois; and Patrick Westhoff from the University of Missouri’s Food and Agricultural Policy Research Institute.

The three keynote speakers spoke on their areas of expertise and covered the three largest agricultural titles in terms of spending within the farm bill: commodities (Patrick Westhoff), conservation (Jonathan Coppess) and crop insurance (Keith Coble).

If you did not attend but would like to know what they had to say last week, check out the Farm Bill Summit by going to

Since it might be wet to be in the fields this weekend, take the opportunity of down time and listen to what the experts had to say.

Tony Nye is the state coordinator for the Ohio State University Extension Small Farm Program and has been an OSU Extension Educator for agriculture and natural resources for over 30 years, currently serving Clinton County and the Miami Valley EERA.

Tony Nye

OSU Extension