This is the common deciduous oak in the conifer belt of the Sierra Nevada.  The large, deeply lobed leaves with bristle-tipped teeth differ from other western oaks.  Slow-growing and long-lived, it is a hardy shade tree.  Deer and livestock
browse the foliage.

The Black oak acorns are favored by the local Mono Indians as the best for their uses.  They gather them in the fall and store in storage bins made of grass.  Great care is exercised to avoid storing an acorn with a worm hole.  If one acorn is contaminated with a worm, it can spoil the entire bin.  When care is used in
storing the acorns, they may be stored for up to 5 years.

Identification of oaks, due to hybrids and variability within the species, is a challenge. Related species of oaks from the same subgenus may share similar characteristics and oaks belonging to a single species may be quite different due to environmental influences. The oaks adapt to the changing climatic conditions,
and this adaptation may change the leaves and acorns in both size and shape.