''Ceanothus otayensis'', the Otay Mountain buckbrush or Otay Mountain lilac, is a plant species known only from the Otay and San Miguel Mountains of

San Diego County San Diego County (), officially the County of San Diego, is a county in the southwest corner of the U.S. state of California, north to its border with Mexico. As of the 2020 census, the population was 3,298,634; it is the second-most populous ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, and in nearby

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. It occurs on dry slopes and brushlands at elevations of 600–1100 m. ''Ceanothus otayensis'' is a shrub up to 120 cm tall, erect, not rooting at the nodes. Leaves are

opposite In lexical semantics, opposites are words lying in an inherently incompatible binary relationship. For example, something that is ''even'' entails that it is not ''odd''. It is referred to as a 'binary' relationship because there are two members i ...

, evergreen, broadly ovate, up to 15 mm long. Flowers are white to pale blue, borne in a spike of umbels. Fruits are spherical, about 5 mm across.Forrest Shreve, & Ira Loren Wiggins. 1964. Vegetation and Flora of the Sonoran Desert. Stanford University Press.

References

{{Taxonbar, from=Q15553738 otayensis Flora of California Flora of Baja California Natural history of the California chaparral and woodlands Natural history of the Transverse Ranges Natural history of San Diego County, California