If you’re going to Palo Alto’s Arastradero Preserve, take I-280 to the Page Mill Road exit and plan to get lost a couple of times.
The 600-plus-acre preserve is unassuming: a small parking lot is edged by grassy hills, while across the road to the west are more open hillsides, a willow-clad creek, a few slopes of oaks, native coyotebrush, and blackberry. You might not even know you’re at a restoration site until you notice the eucalyptus stumps and their neighbors: oak seedlings protected by plastic sleeves or wire cages. A practiced eye catches yet another clue in the freshly planted native bunchgrasses.
The Palo Alto address—and the giant Stanford radar dish peeking like Kilroy over the hill to the east—suggest some of the ingredients that make Arastradero a successful restoration site: civic money, civic will, and happy placement next to “undeveloped” land that serves as a wildlife corridor and seedbank.
The site was set aside in 1969, when a 1,600-home development was proposed; Palo Alto’s own open-space policy forced the city to buy the land. In 2002, the Peninsula Open Space Trust (POST) bought a 13-acre private inholding to forestall more building. The city of Palo Alto has ten years to buy the spot from POST.
Big investments were involved in both these transactions — $3.56 million in the latter, and nearly $4.5 million in 1969. But more important than money is the human input: Arastradero has one of the busiest volunteer schedules in the Bay Area, and its stewards supplement those volunteers with paid help. Most of this is coordinated by the activist coalition Acterra, successor to Bay Area Action (BAA), which has contracted with the city of Palo Alto to supervise restoration, trail maintenance, research, and education.
Once a cattle ranch, the site had “a fabulous old house and barn” and at least one remaining outbuilding when Palo Alto bought it. When the city council decided to remove the buildings, BAA did it responsibly—volunteers dismantled the structures and recycled the materials. “The initial plan was to restore the three sites where the buildings used to be,” says site steward David “Tex” Houston. Wood chips were spread about a foot deep over those areas. After a year or two, volunteers began planting perennials. “For the first three years we planted trees and grasses, and now we’re adding more wildflowers and forbs to the mix to increase diversity,” Houston says. “We’ve been restoring in earnest since 1997, and the last two years have gotten a total of $15,000 for day laborers, which has really made a big difference in keeping weeds out of our revegetation sites.” Houston says that hiring laborers in the spring, when weeds are easier to pull by hand, is key for restoring sites where weeds provide too much competition for fledgling natives.
Volunteers from Acterra and other groups such as Scout troops, students, service organizations, and corporations (drop-ins are strongly encouraged) assemble to pull weeds, plant natives, maintain trails, pull more weeds, harvest native seeds for the project’s shared nursery, construct and monitor nest boxes, and gather data. That last activity makes Arastradero notable among restoration efforts. The managers of most such projects note the big stuff—disruptions, and flushes of noxious weeds—but the crewmembers at this place are practically obsessive about compiling data.
They’re also in Silicon Valley, so it’s no surprise that they’re teched out in some of the newest gadgetry. They use Global Positioning Systems (GPS) to take the guesswork out of invasives control and native replacement. Several told me that GPS has revolutionized the way they handle a number of species on the preserve, because accurate data allows the stewards to set control priorities. The Acterra newsletter is able to reel off species, places, and percentages for several years running: “An area of 19,800 square feet on the lower Meadowlark Trail once composed of 50 percent milk thistle is now down to 20 percent. Similarly, a 4,400-square-foot area on upper Meadowlark Trail that was 75 percent milk thistle is now a mere 15 percent milk thistle.”
Because of the GPS and mapping, the stewards are operating a virtual laboratory of restoration methods. They spread black plastic and tarps to “solarize” soil—kill plants and seeds—in areas where there’s nothing but exotics. Then they immediately plant natives, to give them a head start before the exotics come back. In another spot, they weed by hand; in an area dominated by the dread yellow star thistle, they’ve introduced a European hairy weevil as a biocontrol. This bug lays eggs in the flower’s ovary, and the larvae hatch and destroy both seeds and seed-producing tissue. So far, the critter has proved pretty much specific in its appetite for star thistle. It’s been distributed in various areas of the state; the epithet everyone uses is “promising.”
In another sort of biocontrol, 13 cows were imported for a couple of months late last summer to graze an open grass expanse on the east side of Arastradero Road. “Once again this year,” wrote project director Jan Myers, “we have invited the girls back” to remove the dead thatch from non-native annual grasses, as the native bunchgrasses don’t tolerate thatch well. But Myers favors the goats that were also employed: “They are a truly amazing creature and from this first encounter at the preserve, they appear to be extremely effective at munching through everything.” She cautions that “everything” is literal, so desirable plants need to be screened off.
Mid-tech strategies include timed mowing and discing, and a seed drill was borrowed for planting in quantity last year. One notable bit of information Houston discovered is how well disc-harrowing can control invasive Harding grass—“if disced in the fall approximately two months before it rains. The discing has to expose the roots so that the sun can bake them and kill them.”
Stewards are also working on setting up a trial of the Waipuna system, a bio-friendly weedkilling method from New Zealand that involves hot water and coconut-oil foam. The hardest part of this might be getting the delivery hose to stretch into the weedy spots, though I have to wonder about fending off those sweaty joggers who get the urge for a bubble-bath.
Houston notes that the basic plan—to increase native biological diversity—has not changed, but the stewards do modify techniques “as we learn what works and what doesn’t work or as new information is discovered.” He says researching what others have found successful is important—as is persistence.
The sheer number of volunteers that Acterra marshals is impressive: nearly 1,000 in 2002, and evidently similar numbers in 2003; the count isn’t finished yet. Volunteering is often informal: Brianna Richardson, who monitored nest boxes last year, said she’s spent a lot of time walking the Preserve. “I ran into Tex, and told him I was there pretty much every week with my dog. He said, ‘I have something for you to do.’ Yeah, I was drafted!”
Richardson believes the experience is priceless, especially for younger volunteers. “Some kids just go from home to school to sports to home, and never connect with the place they live, the scenery they see from I-280,” she says. “When they put some time and work into a place like this, they can say, ‘This is where I live.’ It’s clichéd, but they do get a connection.”
Aside from the obvious value of restoring a bit of California grassland and streamside, the data-collecting and tracking and various weed-control and native-replanting methods make Arastradero Preserve valuable as a learning tool. And the continuing involvement of so many community members and groups makes them inclined to cherish it, as we all cherish any place irrigated with our own sweat. That will go further than annuities or legacy arrangements toward protecting Arastradero for its wild inhabitants.