Marin County Sheriff's video and photos show marijuana eradication operations on Mount Tamalpais. The first major grow site there was discovered in 2006; it was a 30-acre garden with at least 50,000 plants.
Marin sheriff's deputy Matt Larson was assigned to the Mt. Tam watershed when that first site was found and is now on the department's marijuana eradication team. He says the large grows are usually backed by the Mexican drug cartels. There's plenty of evidence they have guns.
"Throughout the state, growers are armed and not afraid to engage law enforcement," Larson said.
In 2005 a Fish and Game warden was shot and injured by Mexican nationals guarding a pot farm in Santa Clara County.
Larson is armed, but his counterparts, the Marin Municipal Water District rangers who patrol the watershed, are not. The water district currently has five rangers who cover the district's 22,000 acre watershed. They are supported by two Marin sheriff's deputies assigned there.
The rangers were deputized and carried guns when Trailside Killer David Carpenter was terrorizing the Bay Area 30 years ago, but had to turn them in in 2003 when it was realized they lacked the proper certification. Now they've got that special peace officer status back, but not the guns. The water district's elected board doesn't like the idea.
"I wasn't there during those arguments but Tam is a large open space, closed from sunset to sunrise and designed for passive recreation, that's all we allow up there, so crime is very light," interim general manager Tom Cronin said.
ABC7 were unable to reach any of the board members for comment, and though we'd like to ask the rangers what they think, we're not allowed to -- they signed a 2008 agreement with the district saying they wouldn't talk about.
So, we asked Larson if he'd want to patrol the watershed unarmed.
"No, no I would not," Larson said.
Gary Leo rides his bike in the watershed almost every day. He's aware of the controversy and says he knows that the rangers feel uneasy, but he says he is not.
"I don't ever feel threatened by anyone and with the sheriff's around they're armed and I don't see any need for more firepower up here," Leo said.
"If you're going to put someone in a uniform and badge in this day and age, you can't live in a bubble and assume everything's going to be OK," Marin Conservation League President Larry Minikes said.
Minikes is outraged about the grows threatening the pristine watershed with pesticides and garbage. He thinks it's just common sense to arm the rangers.
"I would prefer to have them to run to with a weapon than being chased by someone with a weapon and them have nothing to help with except a can of mace," Minikes said.
Cronin says the district researching how other similar entities handle rangers and guns and there should be a final decision whether or not to arm rangers within the year.