Ukiah Resource Area, Mendocino County, Bureau of Land Management, California

Project Point of Contact

John Key, State Hazardous Materials Abandoned Mine Lands, and Natural Resource Damage Assessment and Restoration Program Lead, CA

Project Summary

Instances of marijuana growth and harvesting on remote and inaccessible public lands continue to increase.  Not only a problem for the law enforcement community, the growers damage ecosystems by contaminating soil and water and making creeks run dry.  Growers divert creeks, apply fertilizers and pesticides in inappropriate ways, damage native Manzanita trees to shade marijuana plants, and live on site to protect the marijuana plants creating campsite waste and latrines.  Growers living on site pose a direct threat to the safety of visitors and employees.

Without site clean-ups, growers can easily replant “busted” marijuana gardens.  This Bureau of Land Management pilot project used mustangs adopted through the Wild Horse and Burrow Program to pack out contaminants and debris from two illegal marijuana gardens on BLM managed land.  The success of these two marijuana garden clean-ups will be used as a model for future clean ups.

Pit dug as reservoir for gardens at Eight-Mile Valley diverted natural waterway and contaminated soil and water
Photo Caption: Pit dug as reservoir for gardens at Eight-Mile Valley
diverted natural waterway and contaminated soil and water

Project Description

Need and Implementation:

This Waste/Pollution Prevention and Recycling project was initiated to clean up the residue left from old marijuana gardens on public land. The growing and harvesting illegal marijuana gardens on public lands administered by the BLM continues to increase and present a serious safety hazard to visitors and employees.  The damage to water quality, watersheds, and wildlife increases each year.  Creeks that ran all year now dry up in the summer, vehicles are driven cross-country and into designated wilderness where gardens are planted, and deer and bear populations are being ravaged by poaching from the growers living off the land while creating and tending their marijuana gardens.  Most of the illegal gardens are in remote locations where access is difficult and often arduous.  The growers make no distinction between Public lands and undeveloped private lands and often involve both in a large “grow”.

The lands involved have rich, fertile soil and a climate that provides ideal conditions for growing marijuana. The gardens are cleared and plants are put in the ground during the spring, tended and defended throughout the summer, and harvested in late September and October. The typical marijuana garden today ranges in size from 1,000 to 100,000 plants, or more.

They are being located much closer to homes, roads, and recreation sites than in the past because of competition for garden space among the growers.  Individuals and families legally enjoying their public lands are frequently discovering marijuana gardens or being confronted by the growers themselves, sometimes violently.  

These large growing operations often have armed individuals tending the gardens and have no reluctance to menace hikers or nearby residents with their weapons.  Occasionally someone is shot or killed.   BLM law enforcement officers work with County Sheriff's Departments, and Campaign Against Marijuana Planting (CAMP) teams. Headed by the California Department of Justice Bureau of Narcotic Enforcement, CAMP teams were created in 1983 for the primary purpose of eradicating illegal marijuana from public lands in California. BLM law enforcement personnel have come across camps with pole and barbed wire fences and numerous firearms. Growers live on the public land near these sites for months at a time.

These camps contain cooking and sleeping areas which are within view of the cultivation site. The camps have tents, hammocks and sleeping bags on the ground and have been found with large overhanging camouflage tarps as cover for the entire campsite.

Water is diverted from springs and creeks in such quantity that many go dry during the peak of the growing season.  Liquid fertilizer is either poured directly into pools created or augmented in small creeks and siphoned out to the gardens through plastic pipelines or a pit is dug, lined with a tarp, filled with diverted water, and used as a mixing tank.  The first method destroys the creek and contaminates everything downstream while the second method contaminates the surrounding soil.

Gardens are a composite of smaller “cells” which are usually about 100 to 200 plants each.  They are either planted directly into the ground in groups of three with wire mesh tubes around them for protection from rodents and deer or in heavy plastic bags that hold about a cubic foot of soil dug from underneath Madrone trees with rat traps scattered among them.  A gravity-fed water system draws water from up to a mile away in black plastic pipe.  The pipe branches off into each garden “cell” and then into quarter inch diameter “spaghetti tubes” with drip heads to each set of plants.

The garden’s “cells” are made by cutting all but the top branches of Manzanita or other tall brush and piling the cut branches around the perimeter of the “cell”.  The marijuana will grow well in the partial sun while being virtually invisible from the air.  Where the garden “cell” is in a natural opening, baling wire is stretched across from tree branch to tree branch to create a web of wire.  Branches are then cut and put on top of the wire web to create a camouflage canopy for the marijuana growing underneath.  Chicken wire and plastic netting is used as fencing and is pushed into the piled brush to keep small animals out.

Nearby downstream residents are extremely concerned of their drinking water supplies being contaminated.  Hikers, hunters, mountain bikers, horse enthusiasts, and legitimate riders of designated OHV roads and trails are concerned for their safety and, with incidents becoming more common, are choosing to stay away.  Two sites in Cow Mountain Management Area were identified for this clean-up pilot project.  They were selected based on relative ease of access to accomplish as much as possible with the funding available.

Though nearly all gardens require helicopters for raiding and subsequent clean-up access, these particular ones did not.  The first one was located in Eight-mile Valley and the second site was south of Highway 20 adjacent to the Hemlock Ranch and Cow Mountain Ranch and accessible only through private land.  Both marijuana garden sites are in Mendocino County, California and are located southeast and northeast of Ukiah, California.  The Eight-mile Valley project site was approached from a staging area on the single lane unimproved access road through the valley.  The staging activities were confined to the existing road surface and flat land immediately adjacent to the road.  Access to the marijuana gardens uphill was by foot.

Trails were cleared into the gardens by cutting brush to allow foot passage in and materials to be carried out.  The brushed trails are not visible from the road and will not result in attracting illegal ORV use.  All non-natural materials were removed, including chicken-wire fencing, plastic web fencing, plastic pipelines and drip irrigation systems, tarps and trash.  All materials were carried out on foot to the staging area.  Once cleaned, the brush that had been cut to form each garden “cell” was pulled back in from the edges and scattered over the ground to give it a more natural appearance and aid in its natural rehabilitation.

The pipeline uphill to the water sources was removed without cutting trails through the brush.  Pits dug by the growers were cleaned out and filled using the soil that came out of them.  Brush cut to create the trails was scattered back into the cleared trails to render them impassable and help to restore ground cover.  All materials removed were loaded on pickup trucks and hauled to the transfer station for recycling and disposal. The Hemlock Ranch project site was more difficult to access and required two staging areas.  The lower one was on private land owned by the Hemlock Ranch and had a twenty-yard roll-off for receiving non-hazardous materials, vehicle parking, and staging for the pack stock.

The second staging area was located along a four-wheel-drive road that came within a quarter-mile of the marijuana gardens.  Site workers were ferried to and from that site and pickup trucks were used to transport removed materials from there to the roll-off.  A trail was cut by the Hemlock Ranch using their small bulldozer to access the gardens and remove hazardous materials soon after it was raided.  Workers and pack horses used that trail as the access the garden site.

The brush was too thick to allow workers to enter the garden and remove materials efficiently, so trails were cleared into the gardens by volunteers from the Hemlock Ranch using their small bulldozer and a “high blade” method, which results in less soil disturbance and allows quicker recovery than if the blade actually cuts into the soil surface. 

All non-natural materials were removed and taken out on foot via the brushed trails to centralized locations within the garden.  This included plastic pipe, drip irrigation systems, camping equipment, tools, propane bottles, plastic bags, plastic cups, bedding plant trays, fertilizer, rat traps, deer repellant, tarps, garbage, and wire mesh tubes.  Irrigation pipelines that ran uphill to the water sources were removed without cutting trails through the brush.  Overhead wires that were used to support cut brush as a form of camouflage to prevent aerial detection were removed.  Plastic bags filled with soil were emptied and the soil spread back out in the gardens. 

The refuse, totaling about 10 cubic yards, was then loaded on the pack stock and taken out to the second staging area.  It was then transferred to pick-up trucks and transported to the staging area for disposal in the roll-off container.  Brush cut by the growers was scattered back into the areas they had cleared.


The public is looking to the BLM for solutions.  CAMP and other operations to raid the gardens is the first half of that solution, but the follow-up activities to rehabilitate the gardens from the damage by these criminals has been missing.  This pilot cleanup operation has gone a long way in building a strong community trust and recognition of BLM’s commitment to its community and to land stewardship. Our relationship with the communities we live and work with is strengthened by the BLM’s actions against these illegal and unauthorized criminal activities and efforts to restore their damage.  The result is more cooperation and help from the public during a time when it is most needed.  This project successfully used innovative methods such as the use of a pack string of adopted wild horses to remove the waste from the marijuana garden sites and partnerships with local resources to successfully cleanup two former marijuana garden sites and as a result of its success is being expanded statewide as more funding is made available.

Partnering and Cooperative Conservation:

The Ukiah FO in addition to using seven members of their staff as a team, partnered with volunteers from the Wild Horse and Burro Program and neighboring ranchers to successfully complete this pilot cleanup project.  This project has the support of the U.S. Environmental Protection Agency, California Department of Fish and Game,  the California Environmental Protection Agency (Department of Toxic Substances Control, Integrated Waste Management Board, and the State Water Resources Control Board), and Mendocino County.  Many local residents have expressed gratitude and support in this effort.

Mustangs help clean up remote marijuana garden
Photo caption: Mustangs help clean up remote marijuana garden.

Scope of Project Impact:

Over the past five years, the illegal growing of marijuana on public lands within California and in particular in the Ukiah Resource Area (RA) has become a huge issue and a very serious health and safety concern.  In calendar year 2007, Lake County, BLM’s largest land base in Northwest California, ranked number one in illegal garden seizures with over 182,000 plants seized and taken off of public lands.  Mendocino County also within the boundaries of the Ukiah RA ranked third in the State with over 125,000 plants seized. These seizures represent less than 25% of all of the marijuana believed to be illegally grown and cultivated every year off of the public lands.  Based on the number of plants seized annually, the Ukiah Field Office (FO) estimates to have over 300 illegal garden sites complete with infrastructure developments, illegal dumps, and hazardous wastes.

While many of the illegal gardens are raided and the marijuana plants destroyed, the cleanup and rehabilitation of these garden sites has not been done.  Many of the gardens contain herbicides, fertilizers, and insecticides along with rodent fences, human waste, garbage, plastic pipe, camping gear, gardening tools, flammable fuels for gas cooking stoves and gas lanterns, and weapons.  Water sources have often been contaminated and the sources of that contamination are not located and removed during the raid activities.  All of these things are deleterious to wildlife and to the safe enjoyment of our public lands by the public.  These sites were planned to be cleaned up not only because of the hazards they present, but also when leaving the infrastructure in place, the result is future gardens returning in future years. In addition, without removal and rehabilitation, the materials left can continue to contaminate soil and water sources for years.