High Time for Conservation

For years, cannabis has been California’s highest value crop. And because grows were mostly tucked out of sight in the remote, densely forested landscapes of northern California, most Californians were unaware that the industry was quietly devastating the environment.

A few years ago, as the state moved closer to legalization, Conservancy scientists set out to characterize the damage. Because of the hidden nature of the industry, and the danger in accessing cultivation sites, few scientists had been able to put hard numbers to the environmental impacts. So we collaborated with agency staff and researchers who had been monitoring and documenting different aspects of the issue, and jointly published a synthesis of the scope and scale of the environmental impacts.

Our findings were eye-opening.  Cannabis is grown in the hidden corners of California, in mostly undeveloped, remote watersheds that are also home to endangered animals like salmon, steelhead trout, and northern spotted owls. Growers tap small streams at the driest times of year, sometimes drying streams completely, and threatening the survival of fish, amphibians, and other animals. Cannabis plantations can also pollute lands and water, as well as poison wildlife through the unregulated use of pesticides, herbicides, fertilizers, and petroleum fuels. For example, black market growers trespassing on public lands often use rat poison, which accumulates in the food chain, harming or killing rare Pacific fishers and northern spotted owls.