Its thick, ridged bark (resembling alligator hide) and deeply lobed leaves are characteristic, and assist in identification.

The valley oak may surpass 30 meters (98 feet) in height, with a sturdy trunk possibly exceeding 3 m (10 ft) in diameter.

This subgenus comprises numerous oaks from California and elsewhere, which species share similar leaves, acorns, bark and wood pulp.

[11] Valley oak tolerates cool wet winters and hot dry summers, but requires abundant water.

A related wasp species, Feron kingi, produces small galls shaped like Hershey's kisses on leaf surfaces.

[15][16] Difficulties in acquiring valley oak wood as well as issues stemming from its drying such as cracking and warping have shifted its consumption from a general purpose lumber to a primarily niche product.

[10] Tyloses present in the pores of valley oak wood increase its impermeability to fluids allowing it to be used in the production of water-tight vessels.

[10] In 1792, the English explorer George Vancouver noted on his expedition through the Santa Clara Valley, after seeing an expanse of valley oaks: For about twenty miles it could only be compared to a park which had originally been closely planted with the true old English oak; the underwood, that had probably attended its early growth, had the appearance of having been cleared away and left the stately lords of the forest in complete possession of the soil which was covered with luxuriant foliage.

[17]In the year 1861, William Henry Brewer, the chief botanist for the first California Geological Survey wrote of the valley oaks that he saw in Monterey County: First I passed through a wild canyon, then over hills covered with oats, with here and there trees—oaks and pines.

How I wish one stood in our yard at home....I measured one [valley oak] with wide spreading and cragged branches, that was 26.5 feet in circumference.