Gambel oak Fagaceae Quercus
Leaf: Alternate, simple, deciduous. Pinnately lobed with 5-9 moderate-to-deep rounded lobes; 3 to 6 inches long and 2 to 3 inches wide; usually widest above the midpoint; leathery texture. Yellow-green and smooth above; paler and smooth to densely hairy below.
Flower: Species is monoecious; but with separate male and female catkins produced on current year's twigs. Male catkins about 1 inch long; female catkins tiny and in small clusters borne in the leaf axils.
Fruit: Single or clumped acorns about 1 inch long; rounded with a shallow cap covering 1/4 to 1/3 of the nut; mature in one season.
Twig: Young twigs are stout, reddish brown, and slightly hairy; older twigs are darker and smoother; terminal buds are clustered and have distinct overlapping scales.
Bark: Young bark is thin and light colored, turning darker and rougher with age.
Form: A small to medium sized tree (reaching 65 feet tall and 6 feet in diameter) or a thicket-forming shrub.
Looks like: Oregon white oak