CALIFORNIA:  Mexican traffickers are sending a flood of cheap heroin and methamphetamine across the U.S. border, the latest drug seizure statistics show, in a new sign that America’s marijuana decriminalization trend is upending the North American narcotics trade.

The amount of cannabis seized by U.S. federal, state and local officers along the boundary with Mexico has fallen 37 percent since 2011, a period during which American marijuana consumers have increasingly turned to the more potent, higher-grade domestic varieties cultivated under legal and quasi-legal protections in more than two dozen U.S. states.

Made-in-the-USA marijuana is quickly displacing the cheap, seedy, hard-packed version harvested by the bushel in Mexico’s Sierra Madre mountains. That has prompted Mexican drug farmers to plant more opium poppies, and the sticky brown and black “tar” heroin they produce is channeled by traffickers into the U.S. communities hit hardest by prescription painkiller abuse, off­ering addicts a $10 alternative to $80-a-pill oxycodone.