Pollution from illegal marijuana farms deep in California's national forests is far worse than previously thought, and has turned thousands of acres into waste dumps so toxic that simply touching plants has landed law enforcement officers in the hospital.
The volume of banned or restricted pesticides and illegally applied fertilizers in the woods dwarfs estimates by the U.S. Forest Service in 2014, when a top enforcement official testified that the pollution was threatening forest land in California and other states.
California accounts for more than 90 percent of illegal U.S. marijuana farming, with much of it exported to other states from thousands of sites hidden deep inside forested federal land, and more on private property, law enforcement officials said. The state is still developing a licensing system for growers even though legal retail sales of the drug will begin next year, and medical use has been allowed for decades.
Ecologist Mourad Gabriel, who documents the issue for the Forest Service as well as other state, local and federal law enforcement agencies, estimates California's forests hold 41 times more solid fertilizers and 80 times more liquid pesticides than Forest Service investigators found in 2013.