CME corn and soybean prices rebounded today with the December corn contract price back over $4/bushel but November soybeans still under the $10 threshold at $9.76/bushel. Supplies of Brazilian and Ukrainian corn are currently priced at a premium and moving higher. China is capitalizing on cheap U.S. soybean prices by stocking up. The question is where are U.S. corn and soybean prices appropriately priced? The answer is where the market pegs it, though that sounds overly simplistic.   A general rule of thumb is to look at the stocks to use ratio (STU). It is a factor built into most price forecasting models, even though it has its weaknesses. For example, U.S. carryover levels have tightened over time, especially since the governm...