United States, California, Contra Costa, California. Contra Costa County: City of El Sobrante; El Sobrante Ridge, upslope of the terminus of Heavenly Ridge Rd., south of junction of Heavenly Ridge Trail and Manzanita Trail, at end of branch off Manzanita trail, south-facing slope overlooking city of El Sobrante.
37.9666666666667 -122.266666666667
37° 58m N; 122° 16m W
213 meters
700ft
Growing in shale soil near the top of the ridge.
Arctostaphylos pallida, Pteridium aquilinum, Mimulus aurantiacus and Toxicodendron diversilobum, with Quercus wislizini and Quercus parvula var. shrevii nearby.
Small tree, irregularly and widely branching, ca. 20-25 ft. tall. Acorns atypically barrel-shaped.