Shifting trade flows for major agricultural commodities are usually directed by prices and comparative values. When it comes to agricultural trade, it has been said that the direction toward the highest prices is always downhill. It is hard to argue with this truism. In an ideal world, grain will move from where it is in surplus (cheapest) to wherever it is in short supply (highest priced). To prove the point, there have been a number of examples when uncommon comparative values have led to unusual trade flows for major agricultural commodities in recent years.We would contend that the price relationships that have led to most of the unusual trade flows recently are actually rooted in weather. More particularly, they have been the result...