Extended warm weather hastened maturation, but average harvest progress
At the end of the growing season, the rate of dry down of the grain depends on sunshine, temperature, humidity levels, and soil moisture. Corn can most effectively dry down with the least adverse impact on quality amid sunny, warm, dry days. One weather concern at the end of the growing season is freezing temperatures. Early freezing before the grain can sufficiently dry down may lead to lower yield, test weight, and/or stress cracking. Also, if harvested prematurely, higher moisture grain may be susceptible to greater breakage than drier grain.
Typically, 80% of the U.S. corn crop is harvested by the end of October.Although this year’s corn crop was ahead of schedule for maturity, rain hindered a timely harvest. Overall, despite abundant rains in September and October, harvest progressed close to the 5YA rate, with drier areas advancing more quickly to harvest. There was no widespread early freeze that would crack grain or lead to late-season disease and harvest issues.
Fusarium-based ear mold (Gibberella Ear Rot) is promoted by cool temperatures soon after pollination, which was generally not the case in 2016. The mycotoxin DON that is produced by Fusarium is often associated with harvest delay or storage of high-moisture corn. Several localized regions within the Gulf and some of the Pacific Northwest remained wet through harvest, resulting in a few areas of high-moisture corn. Overall, the 2016 season is experiencing an about-average harvest duration, and early-harvested grain will be dried to prevent further disease spread.
Additionally, aflatoxin production is favored by hot temperatures, low precipitation, and drought conditions. While it was warm in a large central portion of the corn-growing region, the plants had few extreme high-temperature days, and were not drought-stressed. Therefore, based on weather, aflatoxin should not be a problem this year.