Use of pesticides, water supplies by California pot growers on public lands raising concerns

California is facing a growing environmental concern in the form of illegal marijuana growers, whose thousands of pounds of herbicides and pesticides, some of them banned in the U.S., are being used in dangerously high doses, Christi Turner reports for High Country News. Add in excessive watering in a state suffering through a drought, and the combination is leading to the destruction of public lands. (Rick Fleming photo: A makeshift reservoir to store illegally diverted water) 

Last year the U.S. Forest Service and law enforcement officials "removed nearly one million marijuana plants across hundreds of sites in California," Turner writes. In 2012, "authorities found 315,000 feet of plastic hose, 19,000 pounds of fertilizer and 180,000 pounds of trash on more than 300 illegal marijuana plantations."

The state has struggled through a drought that has been especially hard on rural areas. Illegal pot growers aren't helping the cause, obstructing and diverting "about 6 gallons of water per plant per day over 150 watering days," meaning that "a trespass grow site with 10,000 plants diverts 60,000 gallons of water per day, or 9 million gallons in a season," Turner writes. "Herbicides and pesticides added to irrigation water seep into the ground and back into the local water supply."

Rick Fleming, director of the High Sierra Volunteer Trail Crew, which cleans up the pot patches, told Turner, "Sometimes it’s 10,000 plants. Sometimes it’s 50 plants. That doesn’t matter so much for us. What matters is the infrastructure that’s left. They’re killing our animals, trashing our forest and destroying our water supply. It’s not so much a political issue as it is just trying to preserve public lands.” (Read more)