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Blue Oak Ranch Reserve
Santa Clara County, California
37.3861° -121.7431° Elev 500m


The majority of Blue Oak Ranch Reserve (BORR) lies within the Upper Sonoran Life Zone. Approximately two-thirds of is drained by tributaries of Arroyo Aguague, itself a tributary of Coyote Creek (via Penitencia Creek), which flows into the southern San Francisco Bay. The streams and the 17 ponds on the ranch represent Sensitive Aquatic Resource Areas and are the habitats where most of the rare species such as the river otter, California tiger salamander, foothill yellow-legged frog and the red-legged frog are found. Riparian areas are also utilized by more than 10 species of neotropical migratory birds including flycatchers, warblers, and vireos. The bowl shaped Arroyo Aguague catchment area is characterized by steep wooded slopes and meadows, and open flats dotted with oaks and coyote brush (Baccharis pilularis). The precipitous Arroyo Hondo is heavily wooded on north and east-facing slopes, while western and southern exposures consist of open grassland or dense chaparral patches. Four species of oak dominate the landscape: blue oak (Quercus douglasii), valley oak (Quercus lobata), black oak (Quercus kellogii), and coast live oak (Quercus agrifolia). Foothill pines (Pinus sabiniana) occur only in the Arroyo Hondo and on the slopes above its confluence with North Creek. Chaparral patches occur on many south-facing and some west-facing slopes. Grasslands are mainly dominated by exotic annuals, but some native perennial grasses are present.

Habitats at Blue Oak Ranch Reserve supports around 130 species of birds, approximately 41 species of mammals, at least seven species of amphibians, more than 14 species of reptiles, around seven species of fish, and hundreds of species of invertebrates. There are 73 vascular plant families at BOR. Of the 462 taxa of vascular plants on the ranch, almost 80% are native.

Customized identification guides
under development

Checklists with images, maps, and links

Albums of site participants

More information



  • Dr. Michael Hamilton, Reserve Director, Blue Oak Ranch Reserve -- hphamilton@berkeley.edu -- 424-704-5908
  • Nancy Lowe, Outreach Coordinator, Discover Life -- nancy@discoverlife.org -- 404-272-4526
Updated: 08 October, 2010
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