California’s beautiful forests are ridden with poison. The culprit? Recreational marijuana.

It’s not the cannabis plant itself that is fatal, however — it is the chemicals that the illegal growers leave behind. Safe permitted marijuana cultivation is not the problem. Legally, a Californian over 21 is allowed to grow up to six marijuana plants at a time on private land without a permit. However, a permit is required to sell marijuana and grow it in mass quantities, and many farmers do not abide by these rules. An example of this? In Humboldt County alone, there are approximately 15,000 private marijuana growers. Only 91 have permits. 

Growers without permits often squat on public land to grow their marijuana, and national forests are frequently their location of choice. Apart from the obvious legality issues with growing unpermitted marijuana on public land, the marijuana grow sites are also guilty of polluting the forests with pesticides, fungicides and rodenticides.

Rodenticide is placed around camp to keep mice and rats away from the plants, and, unsurprisingly, this has killed many native species, such as the small, fluffy and carnivorous mammal known as the fisher. Mourad Gabriel, an ecologist at UC Davis, led a study that linked rodenticides from marijuana farms to fisher deaths. 79 percent of the initially necropsied fishers had been exposed to rodenticide. Already rare, fishers are now becoming more and more endangered.

Along with fishers, owls have also been a target of the poisonings. 80 percent of spotted owl carcasses that were collected in Northwestern California from 2012 to 2015 tested positive to having rodenticide in their system. Deer, foxes, vultures and bears have also been affected.

Water is also being contaminated because of these illegal grow sites. A study published in 2015 states that one-quarter of a national forest’s water is diverted into watersheds to provide water for cannabis plants.

With all this pollution and poisoning going on in California’s forests, one would think stricter regulations would be put in place. Only time will tell. For now, I suggest having local politicians look into the pleading eyes of a dying fisher.