BLOOMINGTON, Ill. — McLean County corn yields “rebounded” from last year with yields similar to 2014 and 2016.
A yield survey by First Mid Ag Services estimates the state’s top corn-producing county to average 211.7 bushels per acre based on samples collected the last two weeks of August.
McLean corn yields averaged 198.8 bushels per acre in 2019 after a record 229.3 bushels per acre in 2018. First Mid Ag Services narrowly missed the 2019 final yield average with a 197.3 bushels per acre projection in last year’s yield survey.
“This year we collected 1,600 samples from 160 locations reaching every township in McLean County,” Craig Thompson, farm manager and broker, said via video.
“This ranks as the fourth highest yield we’ve estimated and the data suggests yields similar to the 2014 (218.3 bushels per acre) and 2016 (218.1) growing season.”
Yields ranged from 110 to 273 bushels per acre across the county.
“While we found ear length and rows around to be slightly above average, ear populations were below average due to wet and cold planting conditions,” Thompson added.
“We sample farms throughout the county and it gives us a good perspective of what we can expect for potential yield. It all started back in 1997 and since 2004 we’ve been within 2% of the U.S. Department of Agriculture’s McLean County yield,” said Ross Perkins, First Mid Ag Services farm manager and broker.
Tyler Roth, First Mid Ag Services farm manager and broker, explained the process used in determining yield estimates with an example of his findings in one field.
“We determined that we have 30,000 harvestable ears per acre. Next we count the number of kernels long on our 10 sampled ears and the number of kernels around on our 10 sampled ears and we then come up with an average,” Roth said.
“We then take the average number of kernels around by the number of kernels long by 30,000 harvestable ears and divide by 80,000, which is the number of kernels we estimate that it will take to make a bushel of corn in the field. With this sample we came up with an estimate of 220.79 bushels per acre in this field.
“We’ve seen a lot of variation this year in ear size across the field due to uneven emergence that we saw in April and May.”