SERPENTINE GRASSLANDS

There are two main areas of serpentine grassland at Stanford, both located in the Jasper Ridge Biological Preserve. These two areas are of limited extent, and the total acreage of serpentine grassland at Stanford is less than 25 acres. These grasslands have not been managed specifically to promote native biodiversity; indeed a “hands off” management policy has been in effect at the Preserve for more than 25 years. This policy was implemented in order to ensure that the inevitable vagaries of multi-year management activities did not unnecessarily affect the long-term research activities at the site. The grasslands do, however, still support an array of native plant and animal species, including California plantain, goldfields, serpentine linanthus, common linanthus, red maids, purple needlegrass, California man-root, California buttercup, poison oak, blue-eyed grass, terrestrial brodiaea, blue dicks, Ithuriel’s spear, yarrow, and common muilla. Native insects are common in the serpentine grasslands at Stanford and the Lepidoptera in particular have been the focus of research efforts. The Bay checkerspot butterfly has been studied annually by Professor Paul Ehrlich’s group at Stanford since 1960. This threatened butterfly subspecies formerly had two relatively robust populations at Stanford (a third “population” has been recorded in the literature [population “G”], but never supported butterflies for more than a few years). The Bay checkerspot butterfly has not been observed at Stanford since 1997 (despite hundreds of hours spent annually looking for them). Several species of long-horn moths are common in the serpentine grasslands (three-striped and flammeusella long-horn moths; note that Opler’s long-horn moth has not been recorded from Stanford).

The serpentine grasslands at Stanford are designated as Critical Habitat for the Bay checkerspot butterfly. The Critical Habitat unit encompassing the serpentine grasslands at Stanford is approximately 330 acres in extent.

A wide range of reptiles, mammals and birds can be found in the serpentine grasslands at Stanford. These, however, are by and large the same species found in the annual grasslands and oak woodlands in the area. Botta’s pocket gophers are typically found in high densities in the serpentine grasslands at Stanford.

Click here to view images of serpentine grasslands.