In the gray half-light of dawn, eight figures creep through the dry pine forest near Quincy, California. Seven of them wear camo uniforms bearing the logos of various government agencies: U.S. Forest Service, National Guard, California Fish & Wildlife, Plumas County Sheriff. Most have blackened faces and assault rifles at the ready. An 11-year-old Belgian Malinois named Phebe and her K9 handler lead the way.
Number eight is tall and dressed in black, with a rumpled bush hat and a Springfield Armory 9mm pistol in a hip holster. With a kaffiyeh wrapped under a dark beard, and eyebrows (in his words) “like two caterpillars about to mate,” Dr. Mourad Gabriel could pass as a local interpreter on a Special Forces raid if this were Iraq or Afghanistan. Instead, he’s a wildlife biologist accompanying law-enforcement agents on an illegal marijuana farm bust.
The group traverses hillsides, fords streams, tiptoes through thickets of fern and willow, trying not to snap twigs or shake saplings. Radios crackle with whispers. Tiptoeing through rough terrain is slow going: It takes almost four hours to go three miles.
At last the goal is in sight: a dense garden of pot plants on a steep slope above Palmetto Creek. The dog team and two others move in while the rest, including Gabriel, hold tight down by the creek. Growers are often armed, and if there are any around, they could make a break for it. Runners usually head downhill.
Word comes back: Nobody’s home. The whole team can enter safely. It’s time for Gabriel to go to work.
A combination of ideal growing weather and proximity to tens of millions of potential customers has always made northern California a great place to grow dope. California was the first to permit medical marijuana, in 1996, and this past November, residents voted “yes” on Prop 64, making California the fifth state to legalize recreational pot. Almost two-thirds of the country’s total legal harvest comes from the Golden State. The crop brought in $2.8 billion in 2015, putting it somewhere between lettuce and grapes, and some estimates project the state’s “green gold rush” could become a $6.5 billion market by 2020.
Even as California embraces the booming legal marijuana market, though, it is also seeing an explosion in illegal cultivation, much of it on the state’s vast and remote stretches of public land. National forests and even national parks have seen a surge in large-scale illegal “trespass grows,” some with tens of thousands of plants spread across dozens of acres. As much as 80 percent of illegal pot eradicated in California is grown on federal lands, and that’s just the fraction that authorities find. (Trespass grows occur in other states in the American West, and even in remote areas back east, but at nowhere near the scale of California.)
The surge has overwhelmed land-management and law-enforcement agencies, whose resources are already stretched thin. Here in the Plumas National Forest, for instance, three USFS officers have to cover some 4,600 square kilometers (1,790 square miles). That’s why so many different agencies are cooperating on this raid.
As the executive director of the non-profit Integral Ecology Research Center (IERC), Gabriel’s usual purview is studying ecosystems and their inhabitants, from big cats to endangered invertebrates. He never expected to find himself packing heat and creeping through the forest, let alone facing other threats to his and his family’s safety. But he has taken up the challenge because of illegal pot growing’s insidious side effects: The lethal poisons growers use to protect their crops and campsites from pests are annihilating wildlife, polluting pristine public lands, and maybe even turning up in your next bong hit.
“There are thousands of these sites in places the public thinks are pristine, with obscene amounts of chemicals at each one. Each one is a little environmental disaster.”
Some 50 different toxicants have turned up at grow sites. (“Toxicants” are manmade poisons, while “toxins” are naturally occurring.) Growers use the poisons to keep rodents and other animals from eating the sugar-rich sprouting plants, from gnawing on irrigation tubing, and from invading their campsites in search of food. Acute rodenticides cause neurological damage and internal bleeding. Animals literally drown in their own blood or stumble around until they’re eaten themselves, passing the poison up the food chain to predators like owls and fishers.
Growers bait open tuna cans with pesticides, which are often flavored like meat or peanut butter, or string up poisoned hot dogs on fishhooks. People have found bears, foxes, vultures, and deer with chemicals from grow sites in their bodies. One study of barred owls (Strix varia) in the Pacific Northwest found that 80 percent of the birds tested positive. And for every animal found, there are probably dozens more in a similar condition.
“It’s a massive problem,” says Craig Thompson, a wildlife ecologist with the U.S. Forest Service. “People don’t tend to grasp the industrial scale of what’s going on. There are thousands of these sites in places the public thinks are pristine, with obscene amounts of chemicals at each one. Each one is a little environmental disaster.” Thompson also studies fishers in the Sierras, and he is one of the few scientists besides Gabriel who studies the problem firsthand. “I can stand at the intersection of two forest roads and generally know of three or four pot gardens within a quarter or half a mile.”
Gabriel and Thompson fear the poisons could spread far beyond each grow site and contaminate the water supply of towns and cities far downstream. The toxicants can leach into the soil and linger for years. Using water monitors, Gabriel has already found organophosphates—nerve agents used to make insecticides and certain types of chemical weapons—several hundred meters downhill from grow sites. “We know it’s happening, we just don’t know the extent, and we don’t know what other chemicals are involved,” he says.
“I never thought that studying wildlife diseases would land me in the middle of the drug war”
“I think they were out of here already, maybe to resupply,” says Chris Hendrickson, a detective with the Plumas County Sheriff’s Office who coordinated the raid. Hendrickson is soft-spoken, with glasses and a light mustache. He’s sifting through the mess of the growers’ campsite, a dirt platform under a camouflage tarp just beyond the last plot. It contains everything a few people would need to live for months: sleeping bags, cots, a propane stove, bug spray, cartons of eggs and bags of rice, potatoes and sugar. Many of the food labels are in Spanish; a jar of pickled nopales—prickly pear cactus pads—sits near a pile of dirty clothes and a solar cell phone charger.
Hendrickson estimates he has gone on about 50 raids in his nine years as an investigator. This one is typical, he says: probably two guys tending the plots for anywhere from two to four months, with occasional food drops and extra help during planting and harvest.
It takes about an hour for the team to chop down or uproot all 5,257 plants. While wholesale prices for illegal pot have fallen by half over the past decade, even at the current rate of around $1,500 per pound, at a rough estimate of a pound per plant, that’s almost $8 million lying in the dirt. Someone’s going to be severely disappointed when they come to check the crop. “These guys will be coming back,” Hendrickson says. “It would be interesting to be a fly on the wall when they see what has happened.”
Pot from illegal sites like this one can end up anywhere. “These guys aren’t growing for the legal recreational market or medical dispensaries—they’re growing to exploit a black market somewhere,” says Mark Higley, a wildlife biologist with the Hoopa Tribe in Humboldt County, whose reservation has seen an explosion in illegal grow sites. While there is no proof that illegal pot ends up in the burgeoning legal market, many familiar with the industry suspect it does.
Law enforcement officials think many trespass grows are set up by Mexican drug cartels, which prefer to ship marijuana from state to state rather than smuggle it over the international border. Growers arrested during raids are often undocumented immigrants in their 20s from Michoacan, experienced in covert agriculture and hard living. They earn around $150 a day for two to four months, much more than they would at a farm or winery.
Captured growers sometimes claim their employers are holding their families hostage until the harvest is collected. Whether or not that’s true, they’re motivated to protect the crop. Hendrickson estimates between a quarter and half of raids turn up some kind of weapon, from crossbows to automatic rifles. He has found elevated sniper positions set up near grow sites.
Growers have followed, detained, threatened, pursued, and shot at officers and civilians, including scientists and field techs. One Forest Service biologist who stumbled upon a grow site in Sequoia National Forest was chased for close to an hour by armed growers. When he briefly lost radio contact, his supervisors feared he had been captured or was dead, but he made it out safely. In a single week in the summer of 2016, two K9 dogs were stabbed while apprehending suspects at trespass grows. (Both survived and have returned to work.)
“I’m worried about my family going hiking and running across one of these, or my friends,” Hendrickson says. Gabriel looks up from counting empty bags of fertilizer. “I’ve hiked and snowmobiled through this drainage,” he says. “We’ve done spotted owl surveys here, too. There’s a nest right over there.”
Pesticides have been the biggest recent game-changer for law enforcement, Hendrickson says. The possibility of coming into contact with a neurotoxin sprayed on a plant or hidden in a Coffee-mate jar makes raids even more dangerous, not to mention slower. “We still make sure a garden is safe when we go in, but now it takes a lot longer to assess if there are dangerous chemicals or not. Safety-wise, it’s huge for us.”
Just walking through rows of plants coated with toxic chemicals can be enough to bring on symptoms like lethargy and headaches—let alone spending hours cutting them down in the hot sun under the wash of a helicopter. Gabriel and his employees have started getting monthly blood tests to check for pesticide exposure.
Some chemical threats are more immediate. At one site Gabriel was inspecting an unfamiliar container full of aluminum phosphide, a poisonous powder used to kill rodents and insects. It had gasified and built up pressure in the heat of the sun. When he touched it, it exploded in his face. Luckily he was wearing a hazmat respirator.
“My biggest fear is that some kid will come across one of those bottles,” Thompson says. “Carbofuran is pink, it looks like Pepto, like candy. Can you imagine what a five-year-old would do with that?”
As the last of the plants at Palmetto are cut down, Gabriel totals up his findings: 3.6 kilograms (8 pounds) of bromodialone, a restricted-use neurotoxic rodenticide, and two bottles of malathion, an organophosphate insecticide that’s basically a watered-down version of the nerve agent sarin. Each bottle is enough to make 1,900 liters (500 gallons) when mixed with water. All of it has to be left behind, at least for now, since moving it would require hazmat protocols and more time and money than anyone has at the moment.
Gabriel’s expertise in wildlife toxicology has become a huge asset to law enforcement, both in terms of keeping officers safe and gathering evidence for prosecution, says Forest Service patrol commander Chad Krogstad. “He’s helping us out tremendously, giving us environmental background data and even testifying in some of our cases.” But the work comes at a cost.
“I gave up being objective about this a long time ago. I think it was the day I looked at a map and saw a grow site maybe 100 yards upstream of a place I’ve taken my kids to play in the water and fish. That makes it a personal issue.”
That evening in a tiny pizzeria in nearby Greenville, the stress of the morning’s efforts shows in Gabriel’s face and posture. Usually he’s fizzing with energy, peppering conversations with “Dude!” and going off on endearingly geeky tangents about chemistry or animal behavior like a kid talking Minecraft. Now he’s glancing at the clock, wondering where dinner is. Three simultaneous orders have overwhelmed the kitchen.
“I never thought that studying wildlife diseases would land me in the middle of the drug war,” he says. “But you can’t just stand by and do nothing.” He’s quick to emphasize that his role is strictly that of an objective observer. He’s not advocating or making arrests; he’s a scientist, collecting and analyzing data and reporting his results—even though that entails going on raids and packing heat, and in the end, seeing his efforts help put people in jail.
“I gave up being objective about this a long time ago,” Thompson says. “I think it was the day I looked at a map and saw a grow site maybe 100 yards upstream of a place I’ve taken my kids to play in the water and fish. That makes it a personal issue.”
It’s an unusual position to be in for a scientist trained in dispassionate data collection and objectivity above all, and one that’s often uncomfortable as well as dangerous. Gabriel’s many published papers and presentations on the topic of pot poisons have raised his public profile significantly. In the heart of drug country, that’s not a good kind of notoriety.
Growing marijuana has been a way of life in northern California for decades. Even though more and more is being grown legally, Gabriel’s inadvertent role as “the scientist who helps cops raid pot farms” has—in some eyes—brought unwelcome attention. In Eugene, near where he lives, strangers at the supermarket and gas station have invited him to go fuck himself. Grower websites have posted the latitude and longitude coordinates of his home, and his office has been burglarized. From the pattern of door and room alarms that were triggered, it looked like the intruder headed straight for his desk. “That means someone was probably watching where I sit,” he says.
The worst fallout came one evening in February 2014. Gabriel and his wife Greta Wengart, who was pregnant at the time, called their two dogs in from the backyard. Nyxo, a 100-pound black lab mix, had been barking at something across the fence. He was a gentle giant they had adopted from a local shelter ten years before, after he had been shot at, tossed from a truck, and left for dead. Nyxo seemed sluggish as he went to sleep. In the middle of the night they heard him throwing up.
Early the next morning Nyxo started drooling and collapsed. Gabriel rushed him to the vet, but the dog slipped into a coma. That afternoon he had to be put down. Mourad helped with the necropsy—“one of the hardest things I’ve ever had to do.” He found Nyxo had been poisoned with brodifacoum, an anticoagulant rodenticide. A reward of $20,000 still has not brought in a single lead. Gabriel and Wengart’s daughter was born two weeks later.
Since then Gabriel has surrounded his house with high-def cameras and motion-sensor lights. He has learned to live with one eye over his shoulder, always scanning for suspicious cars or strangers. “I’m not being ignorant,” he says. “I have to be perceptive, for my family’s sake.”
Wengart is also a biologist, and serves as the IERC’s assistant director. She and Gabriel work closely on grow sites and other projects. “I worry about him less than I used to,” she says. “When he’s doing ground entry, that’s the only time I get nervous.” But that’s the only way to get certain kinds of information, by questioning captured growers, and the only way to make sure no one on the entry team stumbles upon anything toxic. The couple started out working together on busts, but now they try to take turns. Not being in the same place at the same time is both safer and more efficient. “It’s definitely a conscious choice,” she says.
“I think we’re all worried a little about Mourad,” says Higley, who often delivers public presentations along with Gabriel. “I wish he would keep a lower profile.” Higley himself has documented dozens of trespass grow sites on the Hoopa reservation, including one last year, the first, with a cache of carbofuran.
In his defense, Gabriel says legal growers have thanked him in person for drawing attention to the issue of illegal pot grows—not just because of the threat they pose to their profits, but also because the environmental and health risks could tarnish the industry’s overall image.
“It used to be the risks were bears, snakes, driving mountain roads. Now it’s pot gardens.”
Early the next morning, Gabriel and five field techs from IERC park along a dirt road in the hills northwest of Quincy. The brushy slopes bristle with blackened tree trunks, remnants of a forest fire years earlier. The team is here to survey a grow site nicknamed Rattlesnake that was busted in 2015. Henderson is along for security, as is a burly National Guardsman from a specialized unit trained in chemical, biological, radiological and nuclear threats. The Guardsman doesn’t want his name used, and later pulls on a balaclava for a group photo. “Mourad’s a badass,” he says. “He’s smarter than all of us, and he’s a goat on the trails.”
Gabriel goes over security protocols as everyone gears up and tests radios. “No wallets, no cell phones, nothing identifiable.” The chance of dropping something that could lead someone unpleasant to your front door, while tiny, just isn’t worth it. “If you run into a grower, remember: Turn your mic on, and the safety code word is ‘hammerhead.’” He shoulders his backpack and checks his pistol. “Everyone have their mace?”
Personal safety has become a primary concern for anyone doing field work on public land in California, Thompson says. “It’s an entirely different paradigm than five or ten years ago. It pervades every aspect of the job.” It’s too dangerous to send anyone out alone, which means having to pay two people to do a job one could do. Law enforcement regularly declares scientific study areas off limits because of safety concerns.
“My techs are going in with guys with M-16s to recover dead animals, and that’s just to do our normal wildlife job,” Thompson says. Techs are taught to identify signs of illegal grow sites, such as trash, new trails, and sneaker prints in places where people generally don’t wear Nikes. They also learn how to appear as nonthreatening as possible in the field: no camo clothing, scientific equipment in full view. “I have to talk about it in job interviews now when I hire people,” Thompson says. “It used to be the risks were bears, snakes, driving mountain roads. Now it’s pot gardens.” It’s enough to scare away applicants, he says.
With all this in mind, Gabriel and Henderson lead the group up the hillside in the open sun. The field techs, two women and three men in their 20s, are clearly inspired by their boss’s enthusiasm. “This is real-world applied biology,” says Alex Reyer, climbing over a crumbling log. “I feel like I’m actually having some sort of impact for the better.”
Topping a bare ridge reveals Mt. Lassen’s snowy peak just above the horizon. On the other side of the ridge, a wide basin spills to the northwest. Somewhere down there, amid the dense wild lilac bushes and blackened 60-meter (200-foot) snags, is the grow site. Gabriel was on the bust, which netted 16,455 plants growing across 300 vertical meters (1,000 feet). One suspect was captured and another escaped by fleeing down the valley, evading two K9 dogs.
Today the team wants to catalog the environmental damage caused by two large campsites, to help plan a cleanup effort. Step one is finding the three plots, but in the past year, the vegetation has grown more than 2 meters (6 feet). It’s so dense that soon none of the team members can see anyone else. Drifting pollen fills mouths with a bitter taste.
It takes half an hour of sweaty bushwhacking to find the first piece of water tubing. Gabriel turns on a satellite tracker to map the plot, pulls on nitrile gloves, and starts digging through a trash pile inside a burned-out stump. He pulls out a propane canister, red Solo cups used to transport seedlings, a filthy pair of underwear. He counts empty bags and containers out loud: “Twenty pounds of 6-4-6 fertilizer… 50 pounds of 0-50-30… 1 pound of unknown white powdery substance in a Gatorade bottle.”
The irrigation lines lead along what were once rows of thriving plants, now barely visible indentations in the ground. A few still hold dead plants, their buds dry and mildewed. Someone calls in a dead bird on the radio. “Take a swab inside the mouth,” Gabriel replies. “Grab liver or kidneys if you can.”
Suddenly he pulls up short. It’s a single marijuana plant, small but definitely alive. “No way!” Just as quickly, excitement turns to concern. Growers often return and replant a raided site if all the irrigation line is left in place, like here. Could someone be here right now? But the plant has a taproot, which means it wasn’t planted by hand. Somehow it sprouted from a leftover seed, survived a winter buried in snow, and got itself pollinated. “Amazing. I’ve never seen that.” Gabriel shakes his head and takes a leaf sample to test for contaminants.
As it turns out, survival isn’t the only thing exceptional about the plant. Its leaves test positive for carbofuran, most likely from the soil, meaning the chemical persisted much longer than anyone suspected it could. According to official estimates, the chemical should have been gone from the soil within a month. “It’s completely new data nobody would have ever conjured up,” Gabriel says.
Pesticides are showing up on both leaves and buds at trespass grows, Gabriel says, and they appear at detectable levels when the plant is smoked. If any of this harvest makes its way to a medical dispensary, it could end up in the lungs of people who are already immuno-compromised from AIDS or cancer. There hasn’t been any formal research in California yet, but studies and investigations in Colorado and Oregon have found pesticides on marijuana in legal dispensaries, including in products that were supposedly certified pesticide-free. Last year, the Emerald Cup, a major cannabis competition in Sonoma County that focuses on organic growing, started testing entries for pesticides. About a quarter of the concentrates and more than 5 percent of flowers were disqualified.
Higher up the hillside, at the edge of the burn scar, is what looks like a sprawling homeless encampment in the trees. Folding camp chairs, a pile of sneakers, and at least 20 cans of athlete’s foot spray are scattered around a dirt sleeping platform reinforced with logs. Four rolls of unused irrigation pipe as big as truck tires lie near a deep drift of food cans that smells like death. Each roll is a thousand feet long and retails for $250. “All of this was trucked in on someone’s back,” Gabriel says. “This is not done on a whim. This takes organization and capital.”
Just below the campsite are three natural springs, or at least what’s left of them. When Gabriel was doing owl surveys here ten years ago, the trickling springs fed a thriving wetland of willows and alders. To give the pot plants a reliable, controllable source of water, the growers dug out the springs into pools the size of hot tubs, covered with sticks and tarps to hide them from the air. As a result, the wetland is virtually gone.
In a controlled setting, a marijuana plant uses about six gallons of water per day, which over a 150-day growing season comes out to 3,400 liters (900 gallons) of water per plant. Legal growers have found their once-unrestricted water use under increased scrutiny as the state confronted extreme drought conditions. (Some grows in Humboldt County have literally sucked creeks dry, leaving salmon and steelhead to flop and die in puddles.) Under a law passed last June, growers now have to secure official water rights to get a growing permit.
Illegal grows, of course, are another story. Gabriel has estimated that trespass grows use 50 percent more water because of less efficient irrigation systems and added stressors like pests, pathogens, and drier weather at higher elevations. Worse, some trespass growers leave their irrigation systems running around the clock throughout the year, even when nothing is growing. Multiply that by hundreds of thousands of plants and you have a serious water problem. One study by the California Department of Fish and Wildlife estimated that trespass marijuana grows used about 300 million gallons of water per square mile, roughly the same as almond orchards.
To put things into perspective, by Gabriel’s estimates the 1.1 million illegal pot plants removed in California in 2016 would have used somewhere around 1.3 billion gallons of water—as much as 10,000 average California households do in a year. He calculates that this Rattlesnake site alone could have used enough water in a single season to fill seven Olympic pools.
Near one of the springs, an empty jar of ibuprofen lies on the ground. This is where the one grower was caught: Fleeing a K9 dog, he took a bad jump and broke his leg. “I gave him some pills—he appreciated that,” Gabriel says. Not all of Gabriel’s interactions with growers are so friendly: He once had to help tackle a grower who had thrown off a law enforcement officer twice his size.
To keep growers from returning and replanting the site, it will have to be remediated, returned to something like it was before it was planted. By Gabriel’s calculations that would mean removing around 6,000 meters (20,000 feet) of irrigation tubing and hauling out all the trash in 50-gallon bags, probably 40 or 50 in all. The springs will have to be rebuilt to function naturally, an expensive and lengthy process. This site is close enough to a road that all the crap can be hauled out on foot; more remote sites require helicopters.
Remediation requires money and manpower, both of which are scarce to nonexistent—just as they are on the law enforcement end. Out of the roughly 80 grow sites Gabriel and his team have investigated since 2014, they have been able to remediate just 29 so far. “We’d like to get that to a hundred percent, but there’s just no money for it,” he says. “Right now it’s all soft money, grants through our NGO, volunteers helping. I’m on the cusp of putting up a GoFundMe site. Next I’ll try selling cookies.”
He nudges a grimy digital scale with his boot. “How do you clean up hundreds of sites?” he says, with an edge of bitterness in his voice. “That’s a lot of bake sales.”
The biggest trespass grow sites are broken up into dozens of smaller subplots, making it less likely every plot will be busted—and also spreading out the environmental impact. “It used to be a single gaping wound, like a bullet hole,” Gabriel says. “Now it’s a shotgun.”
Last September, the IERC team surveyed two grow complexes in Lassen National Forest. Together they covered 2.6 square kilometers (one square mile), the largest site the team has ever seen. There were 30 camps in all, each with its own cache of rodenticide, and more than 65 kilometers (40 miles) of irrigation tubing that sucked up 269,000 liters (71,000 gallons) of spring water a day.
They also found the carcasses of a bear (Ursus americanus) and a gray fox (Urocyon cinereoargenteus). Test results are still pending, but they’re reasonably sure the fox, at least, is full of poison. Right next to it was the carcass of a turkey vulture (Cathartes aura); by all appearances, it took a bite or two and dropped dead. As he was taking samples, Gabriel watched flies land on the fox and die within seconds. “That night was the longest shower I ever took,” he says.
Twenty years after giving the thumbs up to medicinal marijuana, Californians voted in November to allow anyone over 21 to buy pot legally. By some estimates, Proposition 64 could double the state marijuana market to $6.6 billion by 2020. But as long as the plant is still illegal in other states, the demand that fuels trespass grows will continue.
Gabriel knows he’s fighting the good fight. He also knows he can’t keep going like this forever. Almost all his working hours are eaten up by “drug stuff” now. The raids, the long field days of surveys and remediation, the endless presentations and interviews: It’s rewarding—but draining, too.
He’d like to train other researchers and law enforcement officers to identify and remove chemical threats at grow sites. If enough people learn to do what he does, then he can step aside and become just another researcher again. “But if I stopped right now, it would be gone,” he says.
Morgan Heim has been sneezed on by a whale, stampeded by bison, and nearly mistaken for salmon by hungry grizzly bears, all of which she took as great compliments—especially since they let her live to spy on wildlife for another day. Her work has appeared in such outlets as Smithsonian, BBC Wildlife, National Geographic, High Country News, and NPR among others. You can find more of her work at www.morganheim.com.