I just visited the redwoods in Humboldt and heard a lot about the prevalence of growing marijuana. It is now quasi-legal since it is so easy to get a medical referral. And it is quite popular.
It was interesting to hear about the environmental consequences of public policies towards marijuana. According to the story most marijuana was grown outside with minimal inputs. As policing efforts increased much growing was pushed indoors, which takes a great deal of electricity, up to twenty times more than what a normal home would take.
As production has been pushed to remote areas diesel generators were needed, leading the diesel leak into a stream that the story mentions.
I think the most interesting effect will be what will happen if marijuana is legalized in California. Growers fear a drastic drop in prices that would make it uneconomic to grow indoors. Would the producers then ask for subsidies?
The law of unintended consequences remains in effect. Legalizing marijuana turns it into another farm commodity that works under the principles of agricultural economics. Criminalizing the weed increases prices and might reduce supply leading to even higher prices. The transition is sure to be complicated. Do we really need another drug? An interesting story.