Lines in the Sand

In 1994, the  U.S. Army abandoned its base in San Francisco’s Presidio. In the aftermath, local politicians fought for additional housing, businesses sought retail space, and environmentalists argued for the restoration of sand dunes and wetlands that once covered the area.
The battles continue. Between the restoration of Crissy Field and the leasing of the Letterman Complex to George Lucas, the process has been riddled with controversy. Now environmentalists and residents have squared off over a new plan: to take down a dying stand of trees the Army planted a century ago and replace it with an expanded native dune community.
The proposal and the controversy surrounding it raise questions at the heart of environmental restoration efforts across the country: What is the goal of an open-space restoration project? Is it to restore some of the land’s native ecosystem? Or is it to create and maintain an environment palatable to human tastes?
In May, local columnist Ken Garcia of the San Francisco Chronicle ran a story titled “Sand-huggers run amok at Presidio,” which accused “zealots” of proposing to “level a forest of mature trees to save some sand shrubs.” According to many environmentalists, the column contributed a disastrous dose of misinformation to the controversy.
“Ken Garcia killed it,” says Jake Sigg of the California Native Plant Society, referring to the dunes restoration project. “We’re talking about a public that has not been educated in terms of biology. Here we have a museum that is of living things, living processes, and we should cherish those.”
When the Army gave up its foothold in the Presidio, it transferred the land to the National Park Service. With its mission of “preserving unimpaired the natural and cultural resources and values of the National Park System,” the Park Service began restoring portions of the Presidio to their natural states.
In 1996, it started with 12 acres of the Lobos Creek area — bordered by houses to the south and a stand of Monterey cypress and pine trees planted by the Army to the north and west. The Park Service ripped out concrete, removed invasive species such as iceplant, used bulldozers to re-mold hills out of sand from the creek bed, and planted the area with native species. With the help of hundreds of volunteers, the Lobos Creek Dunes eventually began to resemble what they might have looked like 200 years ago.
Sand dunes once covered much of what is now western San Francisco, along with shrubby plants that could survive in dry, windy conditions. The Xerces blue butterfly, the first North American butterfly known to have become extinct from human disturbance, was last seen in 1941 at Lobos Creek in the Presidio. Now, another dune resident, a tiny member of the sunflower family called the San Francisco lessingia, is in danger of extinction.
The San Francisco lessingia, endemic to the Bay Area, is an annual occurring only in coastal sand dunes. Of the five places the plant lives, four are in the Presidio. Lessingia sprouts in the spring from seed left the autumn before, and inconspicuously grows through the summer before exploding in a cluster of bright yellow flowers. In most of the sand dunes, it is dwarfed in size by native neighbors such as Chamisso’s lupine, coyote bush, coast buckwheat, and sticky monkeyflower, and in numbers by the ubiquitous California poppy.
“There probably was a lot of diversity that we don’t know about,” said Andy Baker of the National Parks Conservation Association. “What we have are the last remaining fragments of a larger, more-diverse ecosystem.”
After the restoration of the Lobos Creek Dunes, the San Francisco lessingia made a comeback, from a low of 19 plants to more than one million in 2000, according to Kevin Schwartz, an independent botanist who returns annually to monitor the dunes. “You see a mature dune community developing, which is great,” he said. “It’s very exciting to see such changes in just a five- or six-year period.”
But the flowers are not out of the woods yet. In 2001, the lessingia population plummeted to about 300,000 plants, and the area in which the plants were found fell by one-third.
The problem, say ecologists, is that  at only 12 acres, the Lobos Creek Dunes are too small to be self-sustaining.  Historically, the sand dunes were a fluid community, whose vegetated areas were interspersed with open spaces that could be colonized by lessingia and other annuals. Winter stormwinds shifted sand around, creating fresh patches to be colonized by annual species that would spring from seed in the spring. Plants that lived on the dunes evolved to take advantage of such disturbances. Non-native annual grasses, like the oats and ripgut brome that now dominate much of the dunes, cement the sand into place, preventing the wind from creating open space where native annuals can grow.
Furthermore, the wind that normally would sweep through the area is blocked by the trees, so the movement of sand so critical to the survival of native plants cannot occur. In addition, the dry dunes rely on water from ocean fog that blows into San Francisco. The trees keep fog from reaching down to the ground where the plant communities can use it.
As a result, the US Fish and Wildlife Service has proposed removing the stand of 3,800 trees and replacing it with additional sand dunes, connecting fragmented plots of dunes that lay on either side of the trees. Separately, the Presidio Trust has also proposed removing a nearby complex of World War II–era houses, over the course of 30 years, and restoring the land to dune habitat.
The proposal has been met with significant opposition. The stand of trees is criss-crossed with paths used by runners and dog-walkers. Many of them argue that sand dunes would not serve the same purpose as the trees, which protect runners from the sun and provide an oasis in the midst of urban sprawl. Residents of Lake Street, which borders part of the Presidio, complain that their views of a forest would be replaced by ugly coastal scrub. Many cannot understand how supposed environmentalists would want to rip down a stand of beautiful trees.
But Jake Sigg says the trees are dying. “What does not come across in the stories I’ve read is that the trees that were proposed to be cut down for recovery are at the end of their lives,” Sigg says. “They are falling down as we speak. This is not a forest, it’s a plantation, built by human beings, that must be sustained by human beings.” That is, even if a decision is made to keep the trees, many would have to be cut down to allow in the sunlight needed to foster new trees.
By contrast, the restoration effort aims to bring back entire communities — and let them take hold on their own.
“What I see is a great variety of different kinds of plants and all sorts of insects, butterflies, birds,” says Sigg. “If you look closely, there is a great deal of excitement here. A natural history class or a biology class could spend a very exciting day out there just observing and discussing what all these organisms are.” Making the case for dunes over non-native trees might have to depend on the teaching in those classes: Without it, the public could continue to perceive the complex and vibrant ecosystems as so much “grainy dust,” as Garcia put it. “Once you understand the biological systems and how they work and their value and their beauty,” says Sigg, “you just can’t destroy them, you just can’t.”

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