… is from page 164 of the 2012 revised and updated edition of Steven Landsburg’s excellent The Armchair Economist; it appears in a chapter in which Landsburg discusses a file that he keeps of mistaken economic commentary:
A few years ago a Florida frost caused the price of oranges to rise so high that growers earned more income than usual. One commentator earned a place in the Sound and Fury file by suggesting that the enormous price increase reveals the growers’ ability to act as a monopoly. In fact it reveals just the opposite: The incident establishes that growers can raise their incomes by killing oranges. If they were able to act in concert, they wouldn’t have waited for a frost.