At other times of the year the brown hills may go unnoticed. But if you look up, you will see outcroppings of the curious serpentine rock, so named because unweathered pieces can be green and scaly like a snake. And nestled in among these outcroppings, the rare and endangered Santa Clara Valley dudleya. (pictured above) Perched on the rock may be a horned lark, or a California quail. And somewhere within the dried foliage, the larvae of the rare and endangered Bay checkerspot butterfly.
The Plants: This area contains at least eight plants identified by the California Native Plant Society as rare or endangered. Four of these are on a federal listing of endangered plants: they are the Santa Clara Valley Dudleya, the coyote ceanothus, the Tiburon indian paintbrush, and the Metcalf Canyon jewelflower. Two more are federally listed species of concern; namely, the most beautiful jewelflower and the Mountain Hamilton thistle.
SANTA CLARA VALLEY DUDLEYA Photo courtesy of Thomas Reid Associates
The Animals: Many of the wild animals here are most easily observed
in the air. The American
kestral is a year-round resident, as is the
black-shouldered kite, and the golden eagle. You may also see the
little horned lark, and you will certainly hear its twittering sound.
Another sound you might hear is the yelping of the coyote, although you
may not get close enough to get a good look. The most famous animal
on the ridge is the Bay checkerspot butterfly, federally listed as threatened
. It is found here because of the unique combination of plants, which,
in turn are dependent on the serpentine rock. In wetlands on the
serpentine you may see the California red-legged frog, federally listed
as endangered.
BAY CHECKERSPOT BUTTERFLY Phote by Paul Ehrlich
The Rocks: The geology of the area is as unusual as everything else about it. Serpentine comes from rock that was once below the ocean floor, and which has been pushed up through fault zones such as the San Andreas, and transformed. It lacks nutrients needed by many kinds of plants, and is high in certain minerals which are toxic to most plants. As a result, unusual plants have evolved in serpentine areas, and many of the invasive grasses and weeds, characteristic of California farmlands, are not able to thrive here.
Experiencing the treasure: You can experience the site by going on one of the field trips conducted there each year and by attending lectures and programs sponsored by the Santa Clara Valley Chapter of the California Native Plant Society .
TIBURON INDIAN PAINTBRUSH Photo Courtesy Thomas Reid Associates
Protecting the treasure: Civilization is very close to this treasured spot and expanding every day. Lines of new homes, factories, golf courses, roads, all are advancing on the serpentine ridges. But they are afforded some measure of protection:
