How much space does a plant need to grow, if its population recently crashed to a single specimen?
In the case of the Franciscan Manzanita, a shrub thought to be extinct in the wild until it was discovered in 2009 growing alongside the Doyle Drive reconstruction project, the federal government thinks the answer is 318 acres in San Francisco.
The U.S. Fish & Wildlife Service will list the species as endangered today (yes, it took three years for the government to rule that a species down to its last survivor is "endangered"). It's also preparing to set aside pockets of the city, stretching from the Presidio to Candlestick Park, as critical habitat where the plant could potentially blossom and recover.
"The Franciscan Manzanita was endemic to the San Francisco Bay Area, so it had a small range," Service spokeswoman Sarah Swenty said. "There's only a certain amount of available habitat still left where the species can thrive."
Botanists have been busily cloning hundreds of new plants from the last remaining specimen, which was moved out of the way of the construction project after it was discovered at a cost of nearly $200,000. Those clones could be planted in the newly protected areas.
The 318 acres of proposed critical habitat, scattered across 11 locations that include Fort Point, Twin Peaks, Starr King Open Space and Bayview Park, were selected largely because they feature the type of erratic Franciscan rock formations and other conditions that are favored by the mollycoddled Manzanita variety. Most of the proposed critical habitat is on parkland owned by the federal and state governments.
Think 318 acres of botanical babying is enough for the shrub? Too much? If you're feeling particularly democratic, you could weigh in on the proposal during a two-month public comment period, or if you can't pull yourself away from the computer, then leave your diatribe in the comment section below.
But if you think that's too much land to virtually bequeath to an unremarkable flat-leafed bush, you're going to run afoul of some environmentalists. They say they plan to push the feds for more.
"I think the areas that they selected are good ones," said Brent Plater, executive director of the San Francisco-based nonprofit Wild Equity Institute. "But I think there are probably going to be a few more."