GMO Free Zones

Mendocino County, California

On March 2, 2004, Mendocino County, California became the first county in the United States to ban the growing of genetically modified crops and animals. Measure H was supported by 57% of the voters.

Marin County, California

Marin County Measure B was passed with 61% vote of support after achieving the endorsements of Marin County’s U.S. Representative Lynn Woolsey, the Marin County Board of Supervisors, the Sierra Club, numerous local farmers and ranchers, and many others—all of whom are listed on the campaign’s website.

Santa Cruz County, California

Santa Cruz County outlawed genetically engineered plants in 2006.

Monterey County, California

GMO-free Monterey County has an initiative in progress.


For towns in Vermont that have passed GMO-free resolutions, see

For GMO ecological impacts, see