CALAVERAS COUNTY (CBS13) — Ruthless criminal organizations behind mass murders, assassinations and kidnappings are setting up shop in the area, right under property owners' noses.
One rancher, who we'll only call James for his protection, now patrols his property armed and ready for his own drug war.
Somewhere in Calaveras County, he agreed to take a CBS13 photographer, producer and reporter on a hike through his property.
He and his men are all armed, with one serving as lookout.
"That way if we get in trouble, he can get us some help," James said.
We're repeatedly warned to keep quiet and be ready to confront a violent marijuana militia willing to do anything to protect their pot.
"You just don't know if you're to run into somebody that wants to shoot you or stab you," the rancher said.
He's talking about the Mexican drug cartel that investigators say has moved onto his land.
The cartel's merciless, menacing and brutal drug-related crimes in Mexico have been chronicled in international news reports.
Now they are his neighbor—low-level workers hired by drug lords to grow marijuana on James' 2,100-acre ranch more than 1,200 miles from the deadly border town of Juarez.
"As soon as we saw that it was a grow, we backed out of here," he said.
James found the first marijuana grow after discovering tire tracks and footprints. There were a thousand plants up to six feet tall. Calaveras County Sheriff's investigators got rid of that grow.
But there's more to the nightmare for James.
"I've got six grows on my property," he said.
He's uncovered thousands of pot plants worth millions of dollars. He believes someone's been working undetected on his land for at least a couple of years.
"I feel that it might slow down a bit, but I don't think it's ever going to go away," James said.
An undercover Calaveras County drug enforcement sergeant says they've cleared more than 50,000 plants in the past year with an estimated street value of more than $50 million.
It's a level of organized crime in numbers they can't keep up with.
"The persons we arrest generally have no information as to who the actual person is behind the growing operation," he said.
They say they're finding grows operated by the cartel all over Northern California. When growers are forced out of one property,they just simply move on to someone else's.
In some cases they return.
Assistant U.S. Attorney Mike Beckwith says he knows why the cartel chooses to work this area.
"This part of Northern California is a very popular area," he said. "You can just get to the freeways so quickly."
He's helped prosecute hundreds of cases, including one of the largest seizures in his district.
It's a case with a clear tie to one of the most well-known Mexican drug cartels, La Familia.
Investigators found Fausto Diaz with 600 pounds of methamphetamine, cocaine and marijuana plants. He worked out of a home in Gilroy that served as a large source for drugs in the Bay Area.
Evidence pointing to La Familia includes detailed ledgers, automatic assault weapons, wiretapped conversations, and of course fat stacks of cash.
This also means a lot of money out of property owners' pockets to clean up the damage and mess left behind.
James says three weeks ago, someone was living in a crude living quarters on his property, complete with a mud oven and stove.
He found another grow on his property when he stumbled on an irrigation pipe that growers had buried underground to run water from a nearby pond.
"They tapped the reservoir, and of course drained all the water, so that affects me and the cattle," James said.
But the most frightening experience for James is when he came face-to-face with two drug smugglers. Luckily in that case, they only watched him as he backed away.
But he says he's also stumbled on clothing hanging on branches, a sign he's been told that they will kill. That's why he now carries lethal weapons and wears a bulletproof vest.
James is now forced to police the vast land that his family's owned for decades, knowing he's sharing it with the most notorious organized criminals in the world, and there's nothing he can do about it.
"You shouldn't have to live this way, you know, in fear, because somebody is on your ground willing to shoot you to protect their grow," he said.
This proliferation is happening as funding for California's Bureau of Narcotics Enforcement was completely cut from the state budget nearly two years ago.
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