Science Spotlight: Santa Cruz Sandhills

by Emma Hiolski

The Santa Cruz sandhills are a unique, fragmented habitat covering about 4,000 acres within the mountains of central Santa Cruz County. Scattered between Bonny Doon, Felton, Scotts Valley and Ben Lomond, the sandhills feature chaparral scrub and Ponderosa pines growing in large swaths of fine white-sand soil.

This sand once covered a seafloor, and was lifted to its present height over the course of 15 million years. If you’re lucky, you might find ancient sand dollars or shark’s teeth in the Zayante sand soil.

The sandhills, the only habitat of its kind, hosts seven kinds of plants, animals and insects found nowhere else in the world. State or federal agencies have listed all of these species as endangered. Development and sand mining have destroyed about 40 percent of the original habitat, ecologists estimate. Invasive species also threaten the ecosystem.

Ironically, fire prevention is another problem. The sparse sandhills habitat has adapted to infrequent but intense fires, says environmental scientist Tim Hyland of California State Parks. “It didn’t burn very often, but when it did it went off like a bomb,” Hyland says. Without regular fires, leaf litter can build up, allowing oak trees and Douglas firs to invade.

Conservationists have helped some native sandhill species return to damaged areas. For instance, the Ben Lomond spineflower has regrown after prescribed burns, Hyland reports. Zayante band-winged grasshoppers have also reappeared in sand quarries, says local ecologist Jodi McGraw, offering hope for the resilience of this fragile environment.

Hikers in the sandhills must stay on marked and mapped trails, McGraw emphasizes. It’s too easy to collapse the burrows of the endangered Santa Cruz kangaroo rat!

Two of the bast places to experience the sandhills are on the observation deck hike in Henry Cowell State Park, and on a rare guided hike to the “forbidden” sandhills at Quail Hollow Ranch County Park.