Corn Harvest Quality Report 2019/2020


Weather plays a large role in the corn planting process, growing conditions and grain development in the field. These, in turn, impact final grain yield and quality. Overall, 2019 was characterized by a late, slow vegetative period (the period of growth between germination and pollination), an extended warm pollination time, a grain-filling period with diverse weather and a slow, intermittent harvest. This crop was planted record-late on average and experienced a rough growing season, with a ‘Good-to-Excellent’ crop condition rating1 well below the 5YA. While a modest corn yield is predicted for 2019, the crop’s average test weight, 100-k weight, true density and protein concentration were lower than the 5YA; while average stress cracks, broken corn and total damage were greater than the 5YA. The following highlights the key events of the 2019 growing season:

    • Cold temperatures and excessive rain delayed and prolonged the planting season, up to six weeks behind the 5YA in Illinois of the Gulf ECA. But the late planting favored quick plant emergence.
    • Pollination (silking stage) occurred one to two weeks later than the 5YA. July weather ranged from wet and warm in the Pacific Northwest ECA to cool and dry in the Southern Rail ECA, with the Gulf ECA being hot and dry.
    • Early grain development in August was mostly cool and wet throughout the U.S. Corn Belt, promoting oil accumulation, but the eastern portion of the Gulf ECA was warm and dry.
    • The second half of grain-fill in September was relatively hot for the whole region but wet in the northern Gulf and Pacific Northwest ECAs, while dry in the Southern Rail ECA, favoring horneous endosperm level.
    • This year’s corn crop had record slowest maturation, which delayed the start of harvest. These delays, coupled with rain and snow in October and November, forced producers to harvest corn at greater than ideal moisture levels, increasing broken corn while decreasing test weight.