Occasionally, the NFF features blogs from our conservation partners looking to highlight critical conservation issues. This post is the first of a two part series examining the scourge of illegal marijuana growing operations on National Forests in Northern California. Thanks to Piper McDaniel, communication coordinator from the Watershed Research and Training Center in Hayfork, California, for submitting the posts and highlighting this important issue.

There’s no reason you would know, or even suspect by looking. On the surface, the rugged terrain of Northern California’s National Forests looks like a postcard. The region’s mountains and valleys are vast and majestic – landscapes of seemingly untouched beauty. The lush carpets of trees are home to picturesque vistas and rivers and to abundant wildlife – deer and mountain lions, bears and spotted owls, beavers and salmon.

They are also home to a vast network of illegal marijuana farms. Known as trespass grows, these illegal operations snake through the mountains, leaving behind a caustic web of chemicals and garbage that wreak havoc on our National Forests. Trinity, Humboldt and Mendocino Counties are collectively known as the Emerald Triangle, an area named and known for its legacy of prolific marijuana farming. The climate and sparse population offer perfect growing conditions, and following California’s legalization of medical marijuana in 1996, the region became a hot box for marijuana cultivation on private lands. The Emerald Triangle is thick with marijuana production, and private land cultivation has become a defining political and economic issue regionally and at a state level.

If the amount of wildlife-destroying toxicants found at each trespass grow site is alarming, it’s even more alarming how many grow sites there actually are.

This triad of counties, preoccupied with the fallout of medical marijuana legalization, houses a wide belt of verdant National Forests that spread through Northern California and represent a significant portion of California’s public lands. As national and regional attention is turned to the percolating social, economic and legal unrest surrounding the nebulous realities of legalization, this wide, deep and fertile terrain of National Forests is quietly under the radar, allowing the insidious presence of trespass grows to spread their chemical tentacles through the landscape.

The realities of trespass grows have been largely overlooked in the media, hidden behind the curtain of legalization in the Emerald Triangle. Like Dorothy finally revealing the behind-the-scenes truth of the Wizard of Oz, conservation groups have begun to pull back this curtain to shed light on the reality of trespass grows – a growing environmental problem polluting our rivers, killing our wildlife and threatening at-risk species that are struggling for survival. These issues are linked by their common use of the land; with farmers flocking to favorable growing conditions, rural regions have already been grappling with the environmental impacts of private land farming, but a growing awareness of the dark realities of trespass grows underscores a new environmental concern.

Trespass grows are large-scale operations, with plant counts numbering anywhere from 1,000-80,000, and they are largely funded and operated by drug trafficking organizations. They are uniformly conducted with flagrant disregard for environmental and social well-being.

The typical trespass grow involves miles of irrigation tubing, fertilizer and pesticides, water diversions, body and poison traps (generally for animals, occasionally for humans) and a lengthy list of caustic chemicals. Strychnine and anticoagulant rodenticides are common, as is Carbofuran, an alarmingly potent insecticide strong enough to kill a bear with less than a quarter teaspoon.

The use of these chemicals causes toxic contamination in all aspects of the ecosystem. After these chemicals are dispersed from grow sites and leeched into the soil and water supply, they slowly make their way through the entire food chain. From insects to scavengers to birds, smaller animals to bigger ones, evidence of chemical contaminants from trespass grows is being discovered.

The presence of trespass grows has risen like a slow tide, seeping through the forests and leaving, literally, tons and tons of garbage and poison behind.

One species that is particularly hard-hit is the Pacific fisher. A smaller relative of the wolverine, Pacific fishers are currently in the process of being listed as a threatened species. In 2014, testing of Pacific fishers in the Emerald Triangle showed an 86% rate of exposure to chemical toxicants, such as rat poisons, that are used at these sites. The number of known fisher deaths resulting directly from trespass grow site toxicants is on the rise as well; four fishers were found poisoned between 2007 and 2012, but now in just a two-year period (2012-2014) nine more fishers were discovered poisoned.

The sites themselves are large. Because they need to be hidden, a single trespass grow is often spread across acres and sometimes miles of forest, which contaminates multiple creeks and watersheds instead of just one. A recent cleanup operation spanned seven sites within the Trinity River watershed in Trinity County. These seven dispersed sites collectively yielded 104 pounds of rodenticide, 8,188 pounds of fertilizer, 8.5 miles of irrigation line, 560 gallons of usable insecticide, and 68 ounces of concentrated carborfuran (equaling 60-70 gallons in diluted form) and 205 fifty-gallon bags of garbage, weighing in at four tons.

If the amount of wildlife-destroying toxicants found at each trespass grow site is alarming, it’s even more alarming how many grow sites there actually are. For decades drug trafficking organizations have been stealthily moving into the forest and planting trespass marijuana grows. On average, law enforcement locates 300-600 trespass grow sites in California each year. There are an estimated 300-500 additional grow sites that go undetected, and it’s likely there are many more. If there are a conservatively-estimated 600 trespass grows (discovered and undetected) in California , each with the average amount of toxicants, this means 9,000 pounds of rodenticide, 70,200 pounds of fertilizer, 726 miles of irrigation line, 4,800 gallons of insecticide, 6,000 gallons of Carbofuran, and 300 tons of garbage are deposited in our forests annually.

The presence of trespass grows has risen like a slow tide, seeping through the forests and leaving, literally, tons and tons of garbage and poison behind. With environmental studies just beginning, the focus has been predominantly in Humboldt, Mendocino, and Trinity Counties, but there are numerous other public lands throughout California that are facing the same challenges. Trespass marijuana grows are silently amassing, and the health of our lands could hang in the balance: our forests run the risk of being brought down in the crossfire of the marijuana marketplace.

Click here to support efforts to clean up trespass grow sites.

For more information about the Integral Ecology Research Center, click here.

National Forest Foundation