Rim Fire May Have Started on Illegal Pot Farm: Official California's national parks are full of them, say authorities By Ruth Brown, Newser Staff Posted Aug 31, 2013 4:59 PM CDT 21 comments Comments Inmate firefighters walk along state Highway 120 as firefighters continue to battle the Rim Fire near Yosemite National Park. (AP Photo/Jae C. Hong, File) (Newser) – A fire chief in California's Tuolumne County quietly revealed an interesting tidbit about the origins of the Rim Fire last week, the San Jose Mercury News reports: officials suspect it was started by marijuana growers. "We don't know the exact cause," he told a town meeting, but said it was definitely "human caused" and that it was "highly suspect that there might have been some sort of illicit grove, a marijuana-grow-type thing. "It wouldn't be the first time. A 2009 fire in Los Padres National Forest near Santa Barbara is believed to have been caused by a campfire at an illegal pot plantation run by a Mexican drug cartel. For the past 10 years, the US Forest Service and local police have been finding more and more huge plantations in hidden in California's national forests, reports the Mercury News. It's easier for drug cartels to just grow pot in California than it is for them to smuggle it in, a sheriff explained after the 2009 fire. "We know that these illegal pot growers are out in our forests, and I think this fire just wiped out a whole bunch of them," says the chairman of the Tuolumne County Board of Supervisors. In June, authorities found 15,000 marijuana plants in a forest adjacent to where the current blaze started. But the Forest Service will not comment on the origins of the Yosemite fire.