An Inconvenient Plant

She isn't alone. Her unlikely kindred spirit is Raven (the man, not the plant). "I had a lot of fun when I was a kid there, wandering around collecting and finding plants," he says. "Fencing or putting certain areas off-limits is quite all right, but it would be an utter tragedy if it was done on a wide scale and kids don't have contact with nature. Putting aside a bigger area and keeping people out of it is kind of problematic."

So, paradoxically enough, converting San Francisco to a more "natural" state may actually make nature less accessible for its residents — and since it will require a maniacal amount of scientific, political, and administrative effort, it certainly won't come about naturally.

After half a century of merely keeping the Raven's manzanita alive, its recovery strategy has shifted into reproduction. In recent years, researchers have uncorked the biggest breakthrough in the plant's history since Peter Raven discovered it on the bluff — at times, however, in spite of themselves.

In 1994, UC Berkeley officials lent the only copy of their detailed research history on the plant to an undergraduate — who promptly lost it. Fourteen years later, garden curator Forbes is still visibly perturbed. But she doesn't need papers to remind her that, in 1995, she led an effort to harvest seed fruits from Raven's manzanitas. She and others plied 4,500 of them with 32 different treatments, including smoke and even sulfuric acid, meant to break the seeds' nigh-impenetrable coating.

For all that travail, 12 plants were germinated. Some of Forbes' seedlings, tall and upright, were obviously the herbal equivalent of the milkman's kids. But others certainly looked like Raven's manzanita. Could all the scientists have been wrong to peg the plant an obligate outcrosser? Could the manzanita have self-pollinated?

In 2004, San Francisco State biology professor Tom Parker commenced genetic testing on the six surviving UC Berkeley seedlings. Parker and technician Craig Reading wrapped up lab work at SFSU's Conservation Genetics Laboratory only this month. And Parker has concluded that three or possibly four of the UC Berkeley plants are 100 percent Raven's manzanita. The population of genetic individuals has suddenly quadrupled (or quintupled).

"Twenty years ago, if you'd have asked me about a single individual of an outcrossing plant and what to do about it, I'd have said you're wasting your money, man," says Parker, a friendly, middle-aged man in no way related to Elvis' former manager of the same name. "The plant was at the literal edge of extinction, and now it has been moved away from that. There's a lot of satisfaction there, I think."

The Presidio has invited every last person who has ever worked on the mother manzanita plant to a June pow-wow to discuss what comes next. You would think Parker's revelations would have the scientists turning cartwheels. But you'd be wrong.

"We'll all get in this room and talk and we might be arguing if this is the best use of our time and resources," Swenerton says. "Can we bring this plant back to a level where it will do well on its own? I don't think so."

With one plant or five, the gene pool for the Raven's manzanita is barely moist. If extinction can come in a form as mundane as a caterpillar, how can the plant evolve to cope with global warming?

Parker sees things differently. "If the plant has selfed [self-pollinated], then it's never too late." At a recent PowerPoint demonstration, he walked the audience through his slicing and dicing of multiple gametes and alleles, illustrating his work with a branching chart resembling a thrice-worked-over NCAA bracket. Heads nodded as Parker predicted a future in which sexually reproducing Raven's manzanitas are once again nestled in San Francisco's rocky hills.

And then Parker made his next suggestion: As soon as you have a viable population, flip your lighter and burn them all.

"Nobody likes to hear that," he explains. "But the only way they reproduce is for the seeds to be stimulated by chemicals from smoke. That's their normal way of doing things." Padlocking the Presidio Fire Department's doors during an electrical storm could do wonders for the Raven's manzanita, he notes, only half-seriously.

For obvious reasons, wildfires are not encouraged in the Presidio, nor is the wanton immolation of rare plants. So, it seems the species will always be tied to humans, reproducing only when and where it sees fit — and that's if scientists are lucky enough to establish viable populations.

Back atop the bluff, Chassé shivers in the howling wind and peeks down at the manzanita, which is illuminated by the last rays of the setting sun. "It's a symbol, and as the last of its kind, it's a powerful symbol," he says. "It's a symbol of saving an ancient species and hope for the future."

Night fell, and Chassé hopscotched the poison oak in semidarkness. He mounted his bicycle again and pedaled home. Almost imperceptibly, the mother plant continued to quake in the wind. It had, improbably enough, survived one more day.