BACKSTORY
Starting in the late 1980s, increasing numbers of industrial-scale marijuana-growing operations were discovered on public land in California, Utah, Arizona and elsewhere. Nearly all of them bore the fingerprints of Mexican drug-trafficking organizations. In addition to using public land illegally, the growers chopped down trees, applied pesticides and fertilizers, and diverted water from nearby streams. Legalization advocates suggested that if marijuana were decriminalized, those problems would diminish (“The public lands’ big cash crop,” HCN, 10/31/05).

FOLLOWUP 
In Colorado, marijuana is now legal. But illegal growing — with all its impacts — continues on public lands. Since 2008, the Forest Service has busted 36 illegal plots in Colorado, seizing more than 100,000 plants. The latest incident happened this fall, when a crop worth $6 million to $8 million was found near Aspen, the second public-land bust in the area this year. So far at least, legal outlets simply can’t keep up with demand, so a profitable black market continues to thrive.