Today's September estimates will include USDA’s first objective yield (field) samples for corn and soybeans. Here are 3 keys we'll be following:

Corn:  Expectations are that USDA will lower its estimate to 14.088 billion bu., based on a Reuters survey of analysts. U.S. yield is expected to be cut to 172.5 bpa.  If USDA uses historical corn ear weights, the estimate isn’t likely to fall as much from last month as some anticipate. 

Soybeans: USDA is expected to lower its soybean estimate as well, but the expected crop would still be up from last year's record production. The yield is expected to be reduced to 51.5 bpa, while the production is expected to be lowered to 4.496 billion bu., based on the Reuters survey.

Acreage: NASS announced it has sufficient data to adjust corn and soybean acreage -- if warranted. We don't expect any major changes on corn acreage, though we expect a 500,000 acre increase for soybeans.

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