As the Illinois corn crop continues its rapid development, with 8% of the crop in dent stage by July 22, its ratings continue to decline.
University of Illinois crop sciences professor Emerson Nafziger notes on July 22, only 7% of the crop was rated as good, none was rated as excellent, and 66% was rated as poor or very poor.
"It's of little comfort, but at least we're getting close to the end of the slide in ratings because they can't get much worse," he adds. "But such low ratings do raise questions about just how poor crop prospects are."
In areas where there has been some rain, at least in the morning before leaves wilt in the afternoon heat, the crop has some ears and retains some green leaf area. What is the chance that such fields, many of which are rated as "poor," will produce a yield that is worth harvesting?
Some reports from recent visits to fields in central Illinois where good and poor fields are often close to one another suggest that the crop might be better than the ratings indicate, depending on whether there is rain. The poor rating may reflect uncertainty about whether conditions will improve.
In dry areas, however, canopy deterioration continues or is complete, with leaf area dead or dying as plants deplete the soil water supply. "We know that many such fields will produce no grain," Nafziger says.