Pioneer stock

On a mid-January morning between San Francisco rainstorms, six horticulturists came to see what one expert calls "the blessed one." They approached not in robes with prayer beads, but in bright yellow safety vests, with pruning shears and spray bottles tucked into utility belts.

At the northern edge of the 1,500-acre Presidio, a former Army base now part of the national park system, they ducked through orange plastic fencing and crossed a closed on-ramp. After stepping onto a triangular wedge of land between two busy roadways, they hovered around the object of devotion: a Franciscan manzanita. For decades, the low-growing shrub was believed extinct in the wild. This specimen was discovered last fall -- right in the path of a $1 billion highway reconstruction project.

With small gray-green leaves on gnarled red-barked branches, the manzanita sprawled over an area the size of a queen-sized bed. Two horticulturists snipped cuttings, while another carefully exhumed a rooted branch. These people weren't taking any chances. The tough old pioneer would soon be transplanted to a new home, and if anything happened to it in the process, they would have cuttings and a rooted clone.

The last time a Franciscan manzanita (Arctostaphylos franciscana) was seen growing naturally was in 1947, when botanist James Roof rescued several specimens from bulldozers at a former cemetery south of the Presidio. He was trying to save remnants of the maritime chaparral -- the community of plants that grew in pockets of harsh serpentine soil among the sand dunes that once covered the San Francisco peninsula. By the mid-20th century, most of the peninsula's exposed soils, whether serpentine or sand, had been capped with buildings. Only the old cemeteries still preserved some wild places, and the cemeteries were being removed for more development. Roof had no idea that a single rogue Franciscan was growing on a serpentine outcrop just a few miles away, hidden by a slouching Australian tea tree.

The manzanita lived unmolested for half a century. Then, in October 2009, a work crew began clearing a path for a new viaduct and tunnel. The crew chain-sawed acres of trees and spread wood chips on low-lying vegetation to smother it. As they were about to cover the manzanita (they didn't know it was the manzanita), they noticed a Highway Patrol car inadvertently parked in the line of fire. So they postponed blowing the chips.

A few days later, conservation biologist Daniel Gluesenkamp drove by at 50 mph and spied the now-exposed manzanita. It can't be, he thought. There were only two manzanita species in the Presidio, and one of them, the Franciscan, he knew to be extinct in the wild. The other, the Raven's, is represented by just one specimen. After two more drive-bys, he thought, "Maybe I found a mate for the Raven's, the loneliest plant in the world."

He called Presidio Trust Supervising Ecologist Mark Frey, who took his colleagues to see the plant. They suspected it was a Franciscan, and DNA tests later confirmed it. "It was like finding the ivory-billed woodpecker," said Frey.

The rare plant couldn't stay where it was, "right in the heart of the watermelon," as Caltrans project manager David Yam described it. Five agencies worked together to draw up a conservation plan and a budget; Caltrans committed $130,000 to prepare, move and care for the plant.

By 4:00 a.m. on moving day, lights flooded the site, the crane had arrived, and Caltrans closed its lanes. A light drizzle fell while professional tree movers trenched around the plant. They hammered steel pipes below the roots, connected the pipes to I-beams, and hitched straps to the corners. "Everybody was respectful," said Mike Vasey, manzanita expert with San Francisco State University. "It was inspiring to watch how gently they moved it," he said of the 22,000-pound bundle of plant, rock and soil.

A Highway Patrol car escorted the flatbed carrying the manzanita through San Francisco's dark streets. After the sun rose, the truck backed down a narrow, mucky road to tuck the plant into its new, undisclosed home in the Presidio near a serpentine outcrop.

"This plant is a fulcrum to bring back not only a species, but the vanished community of maritime chaparral to San Francisco," said Vasey. There are specimens of various chaparral plants in the Presidio, but no complete communities. Not yet, anyhow. In its new location, "the blessed one" will once again be surrounded by native flora and fauna. "It's not the end of the story," said Vasey, "but the beginning."

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