Concept
The California Floristic Province (CFP) is a floristic province with a Mediterranean-type climate located on the Pacific Coast of North America with a distinctive flora similar to other regions with a winter rainfall and summer drought climate like the Mediterranean Basin. This biodiversity hotspot is known for being the home of the Sierran giant sequoia tree and its close relative the coast redwood. In 1996, the Province was designated as a biodiversity hotspot allowing it to join ranks among 33 other areas in the world with many endemic species. To be named a biodiversity hotspot, an area has to contain species and plant life that cannot be found anywhere else in the world. The California Floristic Province is home to over 3,000 species of vascular plants, 60% of which are endemic to the province. The California Floristic Province belongs to the Madrean Region of the Holarctic (or Boreal) Floristic Kingdom. As part of the Madrean Region, it is bordered on its east by the Great Basin Floristic Province, and to the south and southwest by the Sonoran Province (which includes the Mojave, Colorado, Sonoran, and Baja California Deserts). To the north, the region is bordered by the Vancouverian Province of the Rocky Mountain Region, and much of coastal and mountain Northern California and southwestern Oregon are defined as falling into either province depending on a given author's delimitations. With an area of , as defined by Conservation International, it includes 70% of California and extends into southwestern Oregon, a small part of western Nevada and northern Baja California. The province is bordered by, and sometimes defined as partly coincident with, the Rocky Mountain Floristic Region in the north. This boundary is poorly defined as some leading geobotanists, including Robert F. Thorne (Flora of North America) and Armen Takhtajan, include Oregon and Northern California within the Rocky Mountain Province.
