Cal professors on the hunt for edible, nutritious East Bay weeds

UC Berkeley Professor Tom Carlson (left) watches as Professor Philip Stark points out edible plants to student Danny De Santiago on a foraging expedition last week in Richmond. UC Berkeley Professor Tom Carlson (left) watches as Professor Philip Stark points out edible plants to student Danny De Santiago on a foraging expedition last week in Richmond. Photo: Michael Short / Special To The Chronicle Photo: Michael Short / Special To The Chronicle Image 1 of / 13 Caption Close Cal professors on the hunt for edible, nutritious East Bay weeds 1 / 13 Back to Gallery

Philip Stark, chair of UC Berkeley’s statistics department, lunged excitedly for a tuft of dandelions jutting from a sidewalk crack in Richmond, yanked them out and eagerly started chewing.

“People’s immediate response is always 'Ewww.’ But it should be 'Yum,’” he said as he swallowed the fibrous, pungent greens. “Some people don’t recognize food unless it comes in a plastic bag, but in reality we have food all around us.”

Stark and his colleague Tom Carlson, plus a handful of adventurous students, make weekly expeditions across the East Bay in search of edible weeds. They take soil and plant tissue samples, document their discoveries and, of course, sample the bounty.

The goal: Create a website showing where residents can find safe, nutritious and free food growing right in their neighborhoods. The site will provide locations, soil quality information and recipes. They have a $25,000 grant from the university’s Berkeley Food Project

“Whether you like them or not, weeds are here and they’re going to stay here. You can try to get rid of them, but they keep coming back,” said Carlson, a doctor and ethnobotanist at UC Berkeley. “We might as well learn more about them.”

So far, they’ve identified more than 70 wild, edible plants in Berkeley, Oakland and Richmond. The findings range from plantago, also known as cat’s ear, to blackberries to peppermint to fennel. Almost all of the specimens are invasive species from Europe that have taken hold in the Bay Area’s moderate clime and are familiar sights in overgrown lawns and vacant lots.

Improved access to greens

Stark and his crew said they reap the best harvests in working-class neighborhoods. In tonier areas, weeds don’t last long — too often killed with herbicides or replaced with landscaping. The other advantage to focusing on working-class neighborhoods is that some of those areas lack nearby grocery stores, and residents there may find it helpful to learn what fresh produce is growing in their front yard.

Weeds should be celebrated, not reviled, Stark and Carlson said. They require no water, fertilizer or special soil, they’re self-propagating, most of them are edible and, depending on one’s viewpoint, they can be beautiful, Stark and Carlson said.

The leafy weeds, such as dandelion greens, are great in salads or sauteed with a little vinegar and garlic, Stark said.

“Do you ever go to Monterey Market? Chez Panisse? That’s what you’ll see — dandelion greens,” Carlson said. “Except they’re a lot more expensive.”

Carlson has always been interested in the relationship between plants and culture, and he has studied the topic all over the world. Stark only became interested recently, as he started counting different weed species on his walks around Berkeley. Eventually he wanted to learn more about them, and before long he was eating them for dinner.

“After a while, it completely changes the way you relate to the environment when you start seeing food everywhere,” he said. “I’d go to the farmers’ market, but find just as much food walking down the street to get there.”

On a recent foray to Richmond, Stark, Carlson and their students pored over a few residential blocks with clipboards, cameras and field guides, documenting every weed they came across. After two hours, they had covered about three blocks.

At one house, they were studying an overgrown front lawn when the home owner pulled up, angrily slammed the car door and stomped over.

“Get off my property!” he shouted.

But instead of backing off, Carlson politely explained how the man’s front yard was a smorgasbord of edible delights, rich in iron and vitaminC.

“You mean that’s the stuff they charge me $3 a bag for at Safeway?” the man said. “Take all you want.”

At another house, a woman named Brenda Gray spent about 20 minutes with the group, listening intently as they explained the many varieties of oxalis — also known as sour grass, clover or wood sorrel.

“You just never know when you’ll need that information,” said Gray, a clerk. “In case of an earthquake or something at the refinery, it’s good to know we can live off the land if we need to.”

No worse than pesticides

The only caveat to urban foraging, as Stark and Carlson call it, is dog urine. “What about dog pee?” is invariably the first question from newcomers, Stark said.

“My response is always, why not eat dog pee?” he said, noting that dog urine is sterile, nontoxic and easily washed off. “The pesticides on greens you buy at the store are far worse for you than dog pee.”

One of the students, Laura Pérez Olivera, said some of the weeds reminded her of home. Where she grew up, in Oaxaca, Mexico, her mother would wrap tamales in plantain leaves, which coincidentally grow in every sidewalk in the East Bay.

“It’s a way to connect science with culture, especially my culture,” she said. “It’s a way to learn botany that’s not just academic. And it definitely makes me think of home.”

Carolyn Jones is a San Francisco Chronicle staff writer. E-mail: carolynjones@sfchronicle.com Twitter: @carolynajones