This tree is found in the foothills along the western boundary of Yosemite National Park up to about 2000 feet in elevation. It is characterized by the blue-green color of its foliage, which accounts for its common name, and the smooth appearing, light ash-gray, flaky bark. It is a small tree, averaging 30 to 50 feet in height and twelve to sixteen inches in diameter. The stout trunk bears thick branches which form a compact crown. The leaves are deciduous, dropping from the tree during the fall and winter of each year. They are two to three inches long and one-half to two inches wide, and are quite variable in form for the margins are either entire (not toothed) or sinuately lobed (wavy).

As the blue oak is very rare in the park it will not be found by the average visitor in this area. Along the roads in the foothills to the west of the boundary, however, it is a common tree and can be readily noted as one approaches Yosemite National Park from any of the principal nearby towns in the San Joaquin Valley.