SENSE OF PLACE: HOW THE CEDARS GOT ITS NAME

''The Cedars" is located about seven miles north of Cazadero, in the middle of Sonoma County's sparsely populated northwest, one of the most remote places in the region.

It was probably named by the U.S. Geological Survey in the 1940s. Locals have called the area "Red Slide" since the 19th century. "Cedars" refers to the woodlands and pygmy forests of Sargent cypress found there.

This conifer grows only on serpentine soils, which are high in magnesium and iron. Many plants can't survive such conditions; those that can sometimes evolve into new species. Hence, The Cedars is home to at least seven plants found nowhere else in the world, including forms of manzanita, fairy lantern and jewel flower.

This island of rare plants and unusual soils points to a rare geologic event. Long ago, the Earth's mantle pushed through the crust all the way to the surface, creating thousands of acres of peridotite rock. This peridotite weathered into The Cedars' serpentine soils.

Because of its geology, The Cedars' springs and seeps are highly alkaline and saturated with methane and hydrogen. Biologists consider them to be one of the harshest environments on Earth and extremely hostile to life.

If The Cedars sounds otherworldly, it is. Conditions in its springs are thought to resemble that of the early Earth and Mars. Scientists have found unique microbes living in them thought to be fundamentally different from nearly all other known life forms. They may provide clues about life on other planets.

Roger Raiche, who has championed protection of The Cedars for years, calls it "an area of great botanic, geologic, and scenic magnificence." To preserve this hidden jewel, The Cedars is not open to the public, but tours can be arranged via thecedarsfriends@gmail.com.

You can reach Glen Ellen-based historical ecologist Arthur Dawson at baseline@vom.com.