Nature Friendly: The Olympia watershed: A forbidden sand hills journey

“I wandered lonely as a cloud
That floats on high o’er vales and hills,
When all at once I saw a crowd,
A host of golden daffodils.”
~ William Wordsworth
On the biological islands of the Olympia Watershed, silver bush lupine and California goldfields are just breaking through their buds, ready to explode into fields of purple and yellow.
Ancient people named the plant “lupine,” meaning wolf, because they believed the roots stole nutrients from the soil. Actually, the misnamed plant adds nitrogen to Zayante soils, and Romans ate the high-protein seeds.
The California goldfields are aptly named, because, even though the plants produce very tiny flowers, the flowers bloom in such abundance at Olympia that they glow like a sunrise breaking through the earth instead of the sky.
“A perfect time to take a walk,” said Dr. Jodi McGraw, the expert on our unique sand hills parkland, about our April 30 nature walk. “I led one last week, and the buds still had not opened.”
“The sand hills habitat is important, because the Zayante soils percolate down to the groundwater and recharge the Santa Margarita aquifer, which supplies 50 percent of the water that the San Lorenzo Valley Water District uses,” added McGraw, who has a doctorate in integrative biology from University of California, Berkeley, and a Bachelor of Arts in biology and environmental studies from U.C. Santa Cruz. “Ninety percent of the formation is sand particles.”
More than 15 million years ago the sea covered what is now the sand hills, and McGraw will show marine fossils she has found, such as scallop shells and sand dollars, to participants on the walk. “We will go exploring together.”
“The maritime climate of high rainfall with sandy soil has allowed different species to evolve,” she said. Even the poppy that will be in flower is a unique “sand hills” poppy — an ecotype, which means a subdivision of a species that has developed in an isolated population and adapted to a particular environment.
Two endangered insects, the Mount Hermon June beetle and the Zayante band-winged grasshopper, are endemic to the area, with looks that only a biologist could love.
McGraw said she has not seen a jackrabbit since 2003, because of “dogs and loss of habitat.”
“The Santa Cruz kangaroo rat is nocturnal and so rarely seen,” McGraw said. “I don’t often work at the sites they still occupy. The last kangaroo rat I saw was in 2001. However, they were seen by other qualified biologists in 2010.”
The rodent resides only in the sand hills.
Quarrying, horses and illegal off-road vehicles have contributed to habitat degradation in the past. Recently, however, the SLVWD has forged a restoration project, with McGraw and other consultants. Using aerial photos and GIS, she helped pinpoint the location of non-native plant populations in the watershed.
The team has cleared up to 15 acres of invasive species, such as acacia and French broom, which has opened up more rare and valuable sand hills habitat.
Perhaps you have driven up Zayante Road and seen the “No Trespassing” sign on the gate leading into the Olympia Watershed. Our walk will be your free ticket to enter and explore with McGraw.
“I am looking forward to seeing the habitat and restoration and seeing what is coming up anew,” she said. “We’ll see a ton of things, like acorn woodpeckers fretting over their granaries lodged in the Ponderosa pines.”
If you are interested in participating in the walk, please e-mail me.
Carol Carson has been a docent at Henry Cowell Redwoods State Park, taught classes on Big Basin Redwoods State Park for UCSC Extension, and organizes nature walks through a grant from the San Lorenzo Valley Water District. She can be reached at ca****@ca*********.com.