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August 14, 2019

2019 U.S. Crops in Eastern Corn Belt continue Slow Development

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

Corn - I do not fully accept the corn production estimates from the August Crop Report. Even though their corn planted acreage seems high at 90.0 million acres, I have no basis to dispute the number, therefore I am going to use their acreage estimate. I think their percent harvested seems high at 91.1% which is basically the normal percentage. My previous percentage of 88.5% harvested may have been too low, so I increased it this week to 89.5%. I think their corn yield of 169.6 bu/ac is too high and I continue to use a corn yield of 160.0 b/ac

The most recent Drought Monitor indicated an expanded area of abnormally dry conditions extending from eastern Iowa to central Indiana. I think the abnormally dry area will probably continue to expand in the next Drought Monitor.

The 2019 U.S. corn crop is 90% silking compared to 96% last year and 97% for the 5-year average. The corn crop is 39% dough compared to 71% last year and 61% for the 5-year average. The corn is 7% dented compared to 24% last year and 16% for the 5-year average.

There is still 10% of the corn crop that has not pollinated with most of the delayed corn development continuing to be in the eastern Corn Belt. In Michigan 35% of the corn has not pollinated, in Ohio 29% and in Indiana 21% has not pollinated. The eastern Corn Belt also is the driest part of the Corn Belt as well. Illinois is reporting 62% short to very short on soil moisture with Indiana 61% short, Michigan is 58% short, and Iowa is 36% short.

Soybeans - I also have problems with the soybean production estimates in the August Crop Report. Their planted acreage of 76.7 million acres seems low, but I have no way to dispute their acreage estimate, therefore I am going to use their planted acreage. I think their harvested percentage of 98.9% is too high, so I am going to use 98.5% harvested. I also think their soybean yield of 48.5 bu/ac is too high and I continue to use a soybean yield of 45.0 bu/ac.

The 2019 U.S. soybean crop is 82% blooming compared to 95% last year and 93% for the 5-year average. The soybeans are 54% setting pods compared to 83% last year and 76% for the 5-year average. The most delayed soybean development is in the eastern Corn Belt where it is also the driest. In Ohio 31% of the soybeans have not started blooming, in Indiana its 30%, in Michigan its 29% and in Illinois 20% of the soybeans have not started to bloom.

One of the questions in the market is how much longer do the soybeans have before they start to mature. Soybean maturity is triggered to a large degree by the amount of daylight the crop receives, but the maturity can also be influenced by when the soybeans are planted. Generally, for every week that the planting is delayed, the soybeans mature a day later. So, if the soybeans are planted five weeks later than normal, they mature 5 days later than normal.

Another factor that can influence soybean maturity is moisture stress. If soybeans are under severe moisture stress, they can shut down prematurely. If the dryer areas of the eastern Corn Belt do not receive significant rainfall soon, the late planted soybeans that are very short in stature will continue to grow slowly and they may even mature prematurely.