The USDA says the U-S will have more wheat and soybeans in stock at the end of the 2015-16 crop year, less corn than 2014-15.
The department's latest World Agricultural Supply and Demand Estimates report says wheat stocks will be up 84 million bushels to the highest level since the 2010-11 crop year.
Soybean stocks are expected to be up 150 million.
Corn ending stocks are projected to be down 105 million.
The department expects the all wheat season-average farm price to be between 4.50 and 5.50 a bushel.
The soybean price is expected to average from 8.25 to 9.75 a bushel - compared with just over 10 dollars for the 2014-15 crop year.
And the U-S season-average corn price for the 2015-16 crop year is expected to range from 3.20 to 3.80 a bushel - down 15 cents at the midpoint from the 2014-15 outlook.