Fairfield Osborn Preserve

Fairfield Osborn Preserve is a nature reserve on Sonoma Mountain containing eight distinct plant communities including oak woodland, chaparral, and freshwater marsh. The landscape spans different elevations and displays a varied mix of dry and wetter zones.

The site began as a Spanish Land Grant and later became a sheep ranch during the 1800s. The Roth family's donation to The Nature Conservancy in the 1970s transformed it into a protected preserve.

Coast Miwok and Southern Pomo peoples maintained deep ties to this mountain for thousands of years, relying on its resources for sustenance. Visitors walking these trails today can sense the long human history woven into the landscape.

Access is available only through guided Saturday tours that require advance registration beforehand. Visitors explore the trails alongside university students and faculty who lead the walks.

Copeland Creek flows through the preserve year-round, providing habitat for yellow-legged frogs and rough-skinned newts in its permanent water pools. These perennial waterways are a crucial refuge for these species in the region.

Location: Sonoma County

Website: http://sonoma.edu/preserves/osborn

GPS coordinates: 38.34340,-122.59500

Latest update: December 11, 2025 11:02