Marijuana is cultivated in nearly every region of the world, from the jungles of Laos to the arid hills of northern California. It's smoked and enjoyed for medicinal, spiritual, and recreational purposes by an estimated 200 million people worldwide. In Pot Planet, journalist Brian Preston sets out on a global ganja safari to explore strange new cannabis cultures, to seek out new growers, activists, and other reefer revolutionaries ... and to boldly...