One more problem

Of course we need something else to worry about.  And Lester Brown has given it to us: wheat will soon be a scarce commodity.  The leading producers of wheat in Europe have not increased their yields very much in the 21st century. In Asia the situation is the same. Brown is not some nutter or does not appear to be.  He is a MacArthur Fellow, founder of the Worldwatch Institute and founder and president of the Earth Policy Institute.  He notes, "Since 1950, grain yields across the world have tripled. Those days are gone. The pace has slowed. Between 1950 and 1990, the world grain yield increased by an average 2.2% a year. Since then the rise has slowed to 1.3%."  If Brown is right, how do we feed the 3 billion or so more people who will be occupying the earth in the next 35 years?