Diane Williams fought for two years to stop Oakland Unified from spraying the likely carcinogenic herbicide. And, finally, she was vindicated.

One day in June 2016, a gardener visited Oakland’s Horace Mann Elementary School in West Oakland to inspect a plot of vegetables and herbs that she had been maintaining for six years. Suddenly, Diane Williams caught wind of something toxic.

“Some of the plants were dead, and I couldn’t figure it out,” said Williams, who works with Planting Justice, a small farm and nursery in West Oakland.

She said she could smell a chemical odor, too. Suspecting her garden had been poisoned, she called the Oakland Unified School District. Through that phone call and a subsequent meeting with the district’s superintendent and several staff members, she had the explanation for her wilted plants: To control weeds, the school’s groundskeepers were using Roundup, the signature product of Monsanto, now owned by Bayer.