Outlooks for mostly dry conditions this week in the region should allow harvest to pick up after a slow start to the season limited deliveries of fresh supplies to market and contributed to higher corn and soy basis bids in recent days.
A spike in farmer sales following gains in futures on Thursday and Friday also weighed on bids.
Corn bids eased by 6 cents per bushel at a closely watched processor in Decatur, Illinois, late on Friday while bids were down 2-3 cents along the Mississippi and Illinois rivers.
Soybean bids fell 15 cents at a processor in Council Bluffs, Iowa.
But soy bids were narrowly higher at elevators along Midwest rivers, supported in part by strong export demand.
The US Department of Agriculture through its daily reporting system said exporters sold 227,300 tonnes of US soybeans to unknown destinations.