a big pumpkin

A pumpkin fit for Linus. This behemoth weighed 2,624.6 pounds (1,190.5 kg), claiming a new world record October 9, 2016 for Belgian grower Mathias Willemijns at the Giant Pumpkin European Championship in Ludwigsburg, Germany. How much further up can humans push the yield curve? Image credit: Thomas Kienzle/Agence France-Presse/Getty Images.

An article in AgFunder News published on February 1, 2018, reported that a bag of corn had a yield potential of about 500 bushels per acre. In 2017, the US average corn grain yield hovered around 176 bushels per acre, 2 bushels above 2016, and far away from the AgFunder News report. Meanwhile, in 2015 David Hula of Charles City, Virginia produced 532 bushels per acre; one year before, Randy Dowdy of Valdosta, Georgia marked 504 bushels per acre. This caught many experts off guard, sending them back to their research plots to figure out what they were doing wrong. Some even criticized the yield numbers as fake.  In fact, the biophysical limit for corn grain yield was estimated by Matthijs Tollenaar in 1985 at ~1,320 bushels per acre using optimized, yet realistic, levels of quantum efficiency, grain fill duration, harvest and leaf area index parameters. At the time Tollenaar published his estimates, Herman Warsaw had just produced a (then) record-breaking 370 bushels per acre on his Illinois farm. Continue reading