On my trip to New York last week I was reminded of two seemingly obvious facts. First, you shouldn't fly in and out of our recently rechristened "California [Fogbound] Redwood Coast — Humboldt County [Crapshoot] Airport" unless you have a day to spare on either end of your trip. And second, marijuana is everywhere. Like I said, obvious. But it hits home when you leave home. If you could track the many paths of Humboldt's marijuana economy, it would probably look a lot like those route maps printed in the back of in-flight magazines, with lines crisscrossing the country and beyond.

My first reminder came while commiserating with a grizzled guy with camo pants, a dirty ballcap and an eagle tattoo on his forearm. Our flights out had been canceled — his the night before, mine that morning — and we'd just watched longingly as 28 passengers filed onto a plane bound for SFO. We bonded over our waiting list disappointments. Turns out he's from South Bend, Ind., and he'd spent the previous couple of weeks doing construction and electrical work in SoHum. "I can guess what kind of work," I said, like the dork I am. He responded with a knowing smile and a weary tale of spending weeks away from his wife and young son.

A few days later I was walking past two guys lounging on a stoop in Manhattan's Upper West Side when bam! That funny smell from my childhood neighbors' house smacked me in the face. The Gotham pot cloud reminded me of a friend who spent three years growing marijuana in the modified garage of his rented Eureka house, selling his product exclusively to a wholesaler who shipped it by the pound to the Big Apple, where people pay a premium for Humboldt. (That friend is now attending law school in Minnesota, and he paid his tuition up-front.)

When my flight home from SFO was also canceled, I decided to take a bus to my in-laws' house in Santa Rosa, rather than wait seven hours for the next flight home (a good move, since that flight was canceled, too). In their driveway, which sits in a suburban cul-de-sac, the skunky aroma hit me again. Yup, my mother-in-law confirmed, their neighbor is growing, rather brazenly, in his backyard.

It costs U.S. taxpayers about $20 billion a year trying to enforce marijuana prohibition, according to Harvard economist Jeffrey Miron. That's more than four times the budget of the National Cancer Institute. Seventy-five years of expensive marijuana prohibition has done nothing to curb pot consumption — as verified by the informal survey of the U.S. recently conducted by my nose — whereas cancer research is making breakthroughs all the time. The latest? According to a study published in the Anticancer Research journal, cancerous cells in leukemia patients can be killed by compounds derived from — you guessed it — marijuana.

Elsewhere:

Is weed a substitute for hooch? That was one result in a large study on the likely impacts of legalizing recreational marijuana use that's about to be published in The Journal of Policy Analysis and Management. The researchers, D. Mark Anderson of Montana State University and Daniel I. Rees of the University of Colorado, found that medical marijuana legalization at the state level (and the resulting increase in recreational use) corresponds with a 5 percent drop in beer sales and a 9 percent drop in traffic deaths. The authors also found that increased marijuana use correlates with decreased alcohol consumption for people ages 18 to 29, and they cite studies finding that stoned drivers are far less dangerous than drunk drivers. (Sober's still best, though.) "Because the social costs associated with the consumption of alcohol clearly outweigh those associated with the consumption of marijuana," the study says, "we conclude that legalizing the use of recreational marijuana is likely to improve public health, although plenty of unanswered questions remain."