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Nature’s Benefits - Illegal Marijuana Growth Impacts
Marijuana and the Federal Law
U.S. laws differ across the states regarding the recreational and medicinal legal uses of marijuana. With California having legalized recreational marijuana in 2016, demand continues to grow nationwide.
California’s National Forests, with their temperate climates and abundant water resources are often a preferred location for marijuana cultivation. However, marijuana cultivation on National Forests lands is illegal under federal law.
Marijuana grown on California’s National Forests harms the natural infrastructure that supports human, plant, and animal life. Forest ecosystems are sources of Nature’s Benefits: a variety of goods and services that are vital to public health, families, communities, households, industry, and agriculture.
Impacts
The impacts of greatest concern from illegal marijuana grow sites on National Forests are:
The toxic pollution of water, plants and soils
The theft of water through illegal use and diversion
The poisoning of wildlife including Threatened and Endangered Species
Additionally, the removal of native vegetation causes erosion, which degrades the clarity and flow of streams and rivers, which impacts downstream users and aquatic species. Damage in these areas creates and increases fire threats from dried or dead vegetation due to illegal cutting of large expanses of natural vegetation in and around riparian areas.
In 2020, the Dolan Fire that was ignited by marijuana cultivators burned 124,925 National Forest land acres and killed 11 California condors, a federally listed species under the Endangered Species Act. Since 2018, fires ignited by marijuana operations on National Forest lands have burned 23,377 acres of federally designated critical habitat for endangered species.
Illegal marijuana cultivation sites on California’s National Forests negatively impact Nature’s Benefits, particularly water and soil quality. Without expensive cleanup measures for hazardous chemicals, these areas remain contaminated for years. Labor intensive measures are required to restore the land to its natural state, reduce the dangers of soil erosion, and mitigate wildfire risks.
From 2018 to 2020, over 70% of cultivation sites in National Forest lands have been identified to have illegal and banned poisonous pesticides present, including the highly toxic pesticide Carbofuran. This is a significant increase from previous years which showed 35% of 77 National Forest System locations in California had banned or restricted pesticides.1
Carbofuran, is just one highly toxic pesticide. As littles as 7 drops to 1 teaspoon is lethal to a 150lb. person.
40% of watersheds that have been tested downstream from known illegal grow sites on California National Forests have tested positive for pesticides, including Carbofuran. This includes watersheds in remote wilderness areas.2
Wildlife including bears, deer, fishers, mountain lions, foxes, California condors, spotted owls, bobcats, rodents, invertebrates, amphibians, fish and other reptiles are regularly found dead or dying near sites. Many of these were purposefully poisoned by growers with their pesticides.3
Water Use & Diversion
Water is one of the most highly prized and regulated resources in California. About 50% of the state’s water supply originates in National Forests.
In general, outdoor marijuana plants require 6 gallons of water per day to grow. A small-size marijuana grow site consumes at least 1.3 million gallons of water in a 150-day growing season, which is the amount of water 521 people use per day.4
Water for illegal marijuana grow sites is often diverted from rivers and streams. With hundreds of grow sites in existence each year on or within National Forest System lands, it is estimated that millions of gallons of water are diverted from their natural courses on California’s National Forests.
In one case, an illegal grow site on the Lassen National Forest was diverting 80,640 gallons of water per day out of a stream, totaling about 29.4 million gallons annually.5
This had significant negative impacts to the threatened and endangered native Spring Chinook Salmon populations.
Eradication
The U.S. Forest Service Pacific Southwest Region’s Law Enforcement & Investigations Unit locates, investigates, eradicates, arrests, and prosecutes those responsible for illegal marijuana growth on federal lands in cooperation with Federal, State and local jurisdictions. The actual number of cultivation sites on National Forest System lands is predicted higher than the number located.6
From 2015-2018 an average of 225 illegal marijuana grow sites were eradicated annually from California’s National Forests. This included:
1.1 million eradicated marijuana plants.
3,379 acres containing marijuana cultivations.7
5,815 acres of land beyond the immediate grow site impacted by marijuana cultivation activity.8
Unfortunately, this is only a small percentage of illegal marijuana cultivation that is occurring.
How You Can Help
California’s National Forests provide an abundance of Nature’s Benefits to its citizens and visitors: from drinking water to recreation opportunities, to carbon sequestration, to local jobs and income. In addition to the challenges the Forests face from the growing impacts of climate change, wildland fire and other disturbance events like tree mortality, California’s National Forests are threatened by illegal marijuana growers whose activities poison our natural systems that threaten the population’s life sources and wellness.
To restore forest health and resiliency, we need to increase the pace and scale of eradicating grow sites and reclamation activities as part of forest restoration efforts across the state. To do this, we offer a shared stewardship vision to work together, and seek your assistance in bringing more resources to bear for restoration in an effort to sustain these Nature’s Benefits for future generations.
Footnotes:
1. 2020 United States Forest Service Law Enforcement and Investigations Preliminary Data: Dr. Mourad Gabriel
2. 2020 United States Forest Service Law Enforcement and Investigations Preliminary Data: Dr. Mourad Gabriel
3. Thompson, Craig M., Mourad W. Gabriel, and Kathryn L. Purcell. “An ever-changing ecological battlefield: marijuana cultivation and toxicant use in western forests.” The Wildlife Professional. 11 (3): 42-46 11, no. 3 (2017): 42-46
4. 2020 United States Forest Service Law Enforcement and Investigations Preliminary Data: Dr. Mourad Gabriel. San Francisco Resident water usage: 24,000 gallons divided by 46 gallons (average city resident of San Francisco uses 46 gallons of water per day).
5. 2020 United States Forest Service Law Enforcement and Investigations Preliminary Data: Dr. Mourad Gabriel
6, 7, 8. LEIMARS
