Price of corn is half what it was in 2008. Wheat had fallen 70 percent. Given the diesel it takes to run tractors hasn't fallen suit, fewer acres are being farmed.
The world's grain stocks have dropped from four to 2.6 months cover since 2000, despite two bumper harvests in North America. China's inventories are at a 30-year low. Asian rice stocks are near danger level.Then there is water. Aside from the North American Midwest, most agriculture is based on irrigation.
Water supply from Himalayan glaciers is ebbing. The Yellow River has been reduced to "an agonising trickle". It no longer reaches the sea for 200 days a year.Things are going to bad in parts of the world, and our diverting a large portion of our corn crop to make fuel isn't helping.
Farmers are draining the aquifers. Environmentalist Ma Jun says in China's Water Crisis that they are drilling as deep as 1,000 metres into non-replenishable reserves. The grain region of the Hai River Basin relies on groundwater for 70pc of irrigation.
China's water troubles are not unique. North India lives off Himalayan snows as well. Nor can we take fertiliser supply for granted any longer since "peak phosphates" threatens.
Yields could improve. But don't expect to see any changes until after things are bad.