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September 16, 2020

2020 U.S. Corn Yield Estimated at 176.0 bu/ac

Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.

The last week and a half has been the wettest period in two months and the rain was accompanied by cooler temperatures. In fact, it was cool enough for some frost and freezing temperatures earlier last week in the far northern and western Corn Belt. The rains may not have ended the drought in the driest areas, but it put a dent in it for sure. The forecast now is for warmer and dryer weather this week.

These rains have probably stabilized the corn yields. I think the corn was too mature for these improved conditions to have added any yield. Instead, I think they helped to stabilize the existing corn yield.

The condition of the 2020 U.S. corn crop declined 1% to 60% rated good to excellent. The corn is 89% dented compared to 64% last year and 82% average. The corn is 41% mature compared to 16% last week and 32% average and the corn is 5% harvested compared to 3% last year and 5% average.

In the September Crop Report, NASS estimated the corn yield at 178.5 bu/ac, which was down 3.3 bu/ac from the August Crop Report and they lowered the corn harvested acreage by 550,000 acres to 83.5 million acres. The corn harvested acreage was lowered due to the damage from the derecho storm in Iowa. They stated that since some farmers were still finalizing decisions regarding some of the impacted acres, NASS will collect additional corn harvested acreage in Iowa for the October Crop Report. They also indicated that any potential impact from the freezing temperatures of earlier last week will be reflected in future reports.

For the last several weeks, I have been estimating that the corn harvested acreage would decline 500,000 acres from the June Planted Report. I now think it might be more than that due to additional abandonment in Iowa as a result of the storm and some abandonment due to pockets of drought. Therefore, I am going to estimate the corn harvested acreage at 83.42 million acres, which is down 600,000 acres from the June Planted Report. The harvested acreage would then equate to 90.6% of the planted acreage.

I left the corn yield unchanged at 176.0 bu/ac, which is 2.5 bu/ac lower than the USDA. I have a lower yield estimate for several reasons including: there was additional dry weather after the survey was conducted for the September Crop Report so the yields could decline in the dryer areas, there was some frost damage after the survey was completed, and the storm damage in Iowa may not have been fully accounted for.

The situation in Iowa is tricky. If some of the storm damaged fields are zeroed-out, then the harvested acreage would decline, but the statewide yield might be supported because the lowest yields would be eliminated. We will not know the full extent of the damage in Iowa until the harvest has been completed.