HUMBOLDT COUNTY (KPIX 5) — State drug agents told KPIX 5 the number of pot plants growing in California has doubled in the past five years. Marijuana is by far the state’s number one cash crop.

Much of it is growing in the mountains of Humboldt County, where pot has always been big business. But it really took off after the state legalized medical marijuana. Now many are taking advantage and cashing in on California cannabis.

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Detective Chandler Baird of the Humboldt County Sheriff showed KPIX 5 how growers are clear-cutting 100 year old redwoods, leveling hills and sucking dry rivers that are already stricken by drought. Not to mention the violence.

“We do come across a lot of firearms, we have deputies that have gotten into shootings before in these grows,” said Baird. “Some of the ones I have shown you today are definitely known drug trafficking organizations.”

So who are these new gold diggers? Where do they come from? “All 50 states, Latin America, Asia, Bulgaria,” said Baird.

We asked, why Bulgaria? “There’s a lot of money to be made in marijuana,” said Baird.” It’s a modern day green rush.”

Take for example, a marijuana growing operation near the town of Bridgeville. Sheriff’s deputies busted it last year, destroying some 400 pounds of harvested marijuana and almost 2,000 plants. Almost all the 16 suspects arrested were Bulgarian nationals, six on expired visas.

The alleged ringleader, according to the sheriff’s department, is Valentin Marinov. Law enforcement said Marinov has been linked to other known illegal grows. Yet no charges were filed against him or any of the others arrested with him.

For Sheriff Mike Downey it’s frustrating. “The state of California and the Federal Government have changed policy. Marijuana is not as important of a commodity that they are trying to control. So funding has gone way down, which has resulted in lack of enforcement,” he said.

He said it’s like playing whack-a-mole: You bust a few and most come right back. “We are scratching the surface on this. It’s basically out of control,” he said.