China has a vast stockpile of corn it is unable to quit. Why is this so? The gummint introduced a fixed floor price for corn and quest what? Those bloody farmers just kept on growing more of it. I'll bet they used heaps of GM seed and glyphosate to help the job along.
From the WSJ (paywall)
The government this spring scrapped a minimum-price support program for corn started in 2007-08. That program, in which the government bought corn to keep prices above a certain level, had proved so popular that farmers grew more. The stockpile soared, doubling in size between 2009 and now.