Quercus kelloggii, commonly referred to as the California black oak, is a tree species endemic to the western United States. This oak species is known for its large, beautiful leaves and its durable wood, which is used for various purposes. To describe a Quercus kelloggii, one could use the following synonyms: California black oak, Kellogg's oak, Western black oak, or simply black oak. These different names refer to the same species of oak tree and are often used interchangeably. Regardless of the name used, the Quercus kelloggii is a remarkable tree with a unique place in the ecosystem of the western United States.