USDA number crunchers once again surprised grain traders and farmers when the agency raised its yield and production forecasts for corn and soybeans.

The September forecast from USDA-NASS shows corn yields at 169.9 bushels an acre. It was 169.5 bu/acre last month. 

Soybean yields come in at 49.9 bushels an acre, up a half bushel from August estimates.

Pro Farmer Editor Brian Grete analyzes the higher production numbers impact on grain stocks.