Quercus kelloggii, the California black oak or Kellogg oak, is an oak in the red oak section native to western North America.
Young California black oaks
Q. kelloggii in Sequoia National Park.
The acorn is the nut of the oaks and their close relatives ; alternatively known as glans. It usually contains a seedling surrounded by two cotyledons, enclosed in a tough shell known as the pericarp,
English oak acorn
Acorns of the willow oak in South Carolina (from small to large, counterclockwise from center): Q. phellos (willow oak), Q. falcata (southern red oak; top right), Q. alba (white oak), and Q. coccinea (scarlet oak). Scale bar at upper right is 1 cm.
Diagram of the anatomy of an acorn: A.) Cupule B.) Pericarp (fruit wall) C.) Seed coat (testa) D.) Cotyledons (2) E.) Plumule F.) Radicle G.) Remains of style. Together D., E., and F. make up the embryo.
Horses eating acorns. Acorns can cause painful death in equines, especially if eaten in excess.