In the world-renowned California marijuana growing region known as the Emerald Triangle, the telltale "whoop-whoop-whoop" sound from helicopters combing the sparsely populated mountains during pot harvest season typically sends paranoia through the roof.

This year is no exception. For the past month, and the feds have been conducting raids across the Emerald Triangle — Humboldt, Mendocino, and Trinity counties in California — using a massive ex-military chopper bearing a worn-down or scraped off US Air Force insignia, eradicating tens of thousands of plants. But this year, there have reportedly been more cases of state and local law enforcement targeting small farmers with fewer than 50 plants, in compliance with state and local regulations, according to Tim Blake who runs the annual cannabis competition Emerald Cup.

On top of increased law enforcement activity, a new source of anxiety for pot farmers has emerged: a paramilitary, private security firm known as LEAR Asset Management Corp. Operating with a chopper — the same one the local cops rent, according to Blake — the camo-clad, AR-15 assault rifle-toting squad of security guards have been air dropping onto private property eradicating illicit marijuana grows.

Thus far, LEAR has been hired, or at least given consent, by property owners to target trespass grows, where pot farmers sneak onto public or private land and set up a pot farm deep within the Emerald Triangle's mountains and forests.

"Law enforcement just doesn't have the means to take care of it [trespass grows] any longer," Paul Trouette LEAR's founder and CEO, told Talking Points Memo. "That's when the hole began to be filled, in my understanding, of how to put together a cohesive, legal, organized private security firm that is now dealing with these types of issues."

Trouette did not return multiple calls from VICE News requesting comment.

"If you're a large land owner with 5,000 to 10,000 acres, and you can't deal with trespass growers, and law enforcement can't or won't, what option do you have?" Blake told VICE News. "You're going to have to turn to a LEAR. Armed militias like that are doing a necessary evil type of a thing, and if what Paul is saying is true, they seem like they're not eradicating legit growers."

Not to mention, Blake added, there would be no financial incentive for LEAR to conduct law enforcement style operations —the hourly cost of conducting a raid is likely $1,000 to $2,000 an hour.

The reason trespass grows can thrive in the Emerald Triangle is because the region is still rural, has a low population density, and is difficult for property owners to monitor vast tracts of land. As a result, trespass grows have been thriving for decades, according to Mendocino's agriculture commissioner Chuck Morris.

Trespass grows are especially dangerous for property owners because they are predominately operated by Italian, Chinese, Ukrainian, Mexican crime syndicates, according to VICE News sources familiar with the illegal activity. Often guarded by well-armed goons, trespass growers also lay booby traps, hunt wildlife, and cause enormous damage to the environment from the pesticides used in farming.

Dealing with the trespass grows isn't simply an issue regarding the lack of government resources, according to political science professor Jason McDaniel.

"We would like it if there was no private security at all, the police should be able to do it," he told VICE News. "But, it would take a huge concerted effort from the FBI, DEA, and so on, to eliminate the problem altogether — think the FBI versus the mafia in the past."

McDaniel sees LEAR's niche as a classic example of citizens pooling their resources together when an issue grows beyond the capacity of local and state resources to solve it.

"There's no federal organization meant to deal with private property owners. We have a long history of private utilities especially in rural areas, but there are tradeoffs you're going to make — in terms of private security think of Blackwater. There's no accountability if you do get into bad situations," he said.

Law enforcement experts we spoke to agreed that LEAR's eradication operations may have unintended consequences. One source, who commented on the condition of anonymity because he is not an authorized spokesman for his police department, said that "Cops don't hold security guys in high regard. Those guys are mercenaries."

There are real safety concerns for the safety of private security entering trespass grows, which are often booby trapped, and protected by guards with serious artillery, former FBI agent Walter Lamar told VICE News. Lamar served for 19 years in the FBI, and now runs a security-consulting firm.

"Then, what kind of coordinating is going on with law enforcement," he said. "You've got armed security roaming around in the woods, if there's not a coordinated effort, and law enforcement comes across an armed contingent [of LEAR personnel], there could be an unfortunate confrontation."

Coordination with local, state, and federal law enforcement would be industry best practices, Lamar said. "On the one hand it's understandable that landowners would turn to a private security if there isn't enough law enforcement to go around. But stringent coordination is necessary."

One of the reasons for that, he explained, is that if private contractors were to eradicate a particular grow, it's possible that they run the risk of disrupting an ongoing federal or local investigation. "There's the potential for the destruction of evidence."

Regardless of the risks, LEAR is dealing with the slew of environmental consequences trespass grows inevitably carry, consequences that have run rampant for two decades and have remained unchecked, according to Morris, Mendocino county's agriculture commissioner.

"There are so many illegal pesticides around these grows," he told VICE News. "Not only are the grows completely illegal but an awful lot of them are clear cutting through all the fauna, killing deer, bears, and other animals for food and to protect their marijuana crops. Then there's the water pollution, water diversion, plus the human waste which includes feces and garbage."

In a video posted by the Jere Melo foundation, LEAR security guards can be seen cleaning up all kinds of trash at a then-abandoned trespass grow on Mendocino Redwood Company property.

Morris said his agency initially consulted with Trouette regarding the various pesticides used in trespass grows, none of which have been certified by the Food and Drug Administration for safe use on marijuana — largely because the drug remains illegal under federal law.

Beyond the environmental costs of trespass grows — which Morris called "off the charts ridiculous" — he worries about the health consequences of toxic pesticides used. A common chemical used in trespass grows is Carbofuran, an insecticide that's absorbed into a plant via its root structure, and banned by the FDA on all food grown for human consumption. Yet Carbofuran is regularly used by trespass growers, and because plants absorb it, likely still present when the marijuana is consumed, Morris said.

If anything, the potential health consequences of these trespass grows is an argument in favor of federal legalization. With oversight, taxation, and regulation, it's likely the black market for marijuana would shrink, if not disappear altogether, according to Amanda Reiman of the Drug Policy Alliance.

"By regulating where marijuana can be grown, we gain control over production sites since they must be licensed," she said in an email. "We do not see the same issues with trespass growing in other industries like wine."

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