I’d heard before that marijuana is the biggest cash crop in California …in Kentucky …in the US. Online you can see a 2006 estimate that puts marijuana on top by Jon Gettman. It always sounded patchy, and here Kevin Drum links to a critical site that estimates the retail value of the cannabis sales at $10 billion.
Even this seems high according to my estimate. I recently (can’t lay my hands on the figure) saw a graph of pot smoking by age in the US within the past month. Highest for people in their 20’s, then about 10% until people hit 60. Older folks smoke very little. So let’s say 10% of people from 15-60 (roughly 24 million people) smoke twice a month:
24 million people x 24 joints/year / 40 joints/ounce x $100/ounce = $1.5 billion retail per year.
By comparison, the US corn crop is $24 billion/year. $1.5 billion/year is about the size of the US tobacco or orange crop. But then we are comparing retail prices to farm prices. So figure growers are getting at best 1/5 or 1/10 or the retail price, and now the marijuana crop is tiny, smaller than the peach crop. Also, considerable marijuana in the US is imported, so the US crop is even smaller.
Running the estimates in the other direction, the $10 billion estimate of spending on marijuana has the monthly US smokers lighting up every other day. This sounds too high, most smokers are occasional smokers. Estimating pot spending at $35 billion as Jon Gettman does has monthly pot smokers averaging eleven joints a week, or every man, woman, and child in the country lighting up once a week. Way high.