The California chaparral and woodlands is a terrestrial ecoregion of southwestern Oregon, northern, central, and southern

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

(

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

) and northwestern

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

(

Mexico Mexico (Spanish language, Spanish: México), officially the United Mexican States, is a List of sovereign states, country in the southern portion of North America. It is borders of Mexico, bordered to the north by the United States; to the so ...

), located on the west coast of

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...

. It is an ecoregion of the

Mediterranean forests, woodlands, and scrub Mediterranean forests, woodlands, and scrub is a biome defined by the World Wide Fund for Nature. The biome is generally characterized by dry summers and rainy winters, although in some areas rainfall may be uniform. Summers are typically hot in ...

biome A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...

, and part of the Nearctic realm.

Setting

Three sub-ecoregions

The California chaparral and woodlands ecoregion is subdivided into three smaller ecoregions. * California coastal sage and chaparral ecoregion: In southern coastal

and northwestern coastal

, as well as all the Channel Islands of California and Guadalupe Island. * California montane chaparral and woodlands: In southern and central coast adjacent and inland California, covering some of the mountains of: the

Coast Ranges The Pacific Coast Ranges (officially gazetted as the Pacific Mountain System in the United States) are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico. Although ...

; the Transverse Ranges; and the western slopes of the northern Peninsular Ranges. * California interior chaparral and woodlands: In central interior California surrounding the California Central Valley cover the foothills and the Transverse Ranges and Sierra Nevada.

Locations

Most of the population of California and Baja California lives in these ecoregions, which includes the

San Francisco Bay Area The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area G ...

, Ventura County, the

Greater Los Angeles Area Greater Los Angeles is the second-largest metropolitan region in the United States with a population of 18.5 million in 2021, encompassing five counties in Southern California extending from Ventura County in the west to San Bernardino ...

San Diego County San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the U.S. state of California. As of the 2020 census, the population was 3,298,634, making it California's second-most populous county and the f ...

, Tijuana, and Ensenada, Baja California. The California Central Valley grasslands ecoregion, as well as the coniferous Sierra Nevada forests, Northern California coastal forests, and Klamath-Siskiyou forests of northern California and southwestern

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

, share many plant and animal affinities with the California chaparral and woodlands. Many botanists consider the California chaparral and woodlands, Sierra Nevada forests, Klamath-Siskiyou forests, and Northern California coastal forests as a single California Floristic Province, excluding the deserts of eastern California, which belong to other floristic provinces. Many

Bioregionalists Bioregionalism is a philosophy that suggests that political, cultural, and economic systems are more sustainable and just if they are organized around naturally defined areas called bioregions, similar to ecoregions. Bioregions are defined thro ...

, including poet Gary Snyder, identify the central and northern Coast Ranges, Klamath-Siskiyou, the Central Valley, and Sierra Nevada as the Shasta Bioregion or the Alta California Bioregion. Santa monica mountains canyon

Flora

The ecoregion includes a great variety of plant communities, including

grassland A grassland is an area where the vegetation is dominated by grasses ( Poaceae). However, sedge ( Cyperaceae) and rush ( Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur na ...

s, oak savannas and

woodland A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the '' plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...

s, chaparral, and coniferous forests, including southern stands of the tall coast redwood (''Sequoia sempervirens''). The flora of this ecoregion also includes tree species such as Gray or foothill pine (''Pinus sabiniana''),

Scrub oak Scrub oak is a common name for several species of small, shrubby oaks. It may refer to: *the Chaparral plant community in California, or to one of the following species. In California *California scrub oak (''Quercus berberidifolia''), a widespr ...

(''Quercus dumosa''), California buckeye (''Aesculus californica''), the rare Gowen cypress (''Cupressus goveniana)'', the rare Monterey cypress (''Cupressus macrocarpa''), and a wealth of

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

plant species, including the extremely rare San Gabriel Mountain liveforever (''Dudleya densiflora''), Catalina mahogany (''Cercocarpus traskiae''), and the threatened most beautiful jewel-flower (''Streptanthus albidus'' ssp. ''Peramoenus''). (material included verbatim under th
CC BY-SA 3.0 license
/ref> Hesperoyucca whipplei, colloquially known as Chaparral Yucca, is commonplace throughout the lower elevations of the climate zone. There are two types of chaparral: soft and hard chaparral. Hard chaparral is usually

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

, located at higher elevation and is harder to walk through. Soft chaparral tends to be drought deciduous, live at lower elevations and tends to be easier to walk through.

Fauna

Species include the California gnatcatcher (''Polioptila californica''),

Costa's hummingbird Costa's hummingbird (''Calypte costae'') is a bird species in the hummingbird family Trochilidae. It breeds in the arid region of the southwest United States and northwest Mexico; it winters in western Mexico. Taxonomy Costa's hummingbird was ...

(''Calypte costae''),

coast horned lizard The coast horned lizard (''Phrynosoma coronatum'') is a species of phrynosomatid lizard endemic to Baja California Sur in Mexico. As a defense the lizard can shoot high pressure streams of blood out of its eyes if threatened. Taxonomy It was ...

(''Phrynosoma coronatum''), and

rosy boa ''Lichanura'', the rosy boas, are a genus of snakes in the family Boidae. They are distributed across the southwestern United States and northwestern Mexico Mexico ( Spanish: México), officially the United Mexican States, is a country in ...

(''Lichanura trivirgata''). Other animals found here are the Heermann kangaroo rat (''Dipodomys heermanni''), Santa Cruz kangaroo rat (''Dipodomys venustus''), and the endangered white-eared pocket mouse (''Perognathus alticolus''). Another notable insect resident of this ecoregion is the rain beetle (''Pleocoma'' sp.) It spends up to several years living underground in a larval stage and emerges only during wet-season rains to mate.

Fire

Chaparral, like most Mediterranean shrublands, is highly fire resilient and historically burned with high-severity, stand replacing events every 30 to 100 years. Historically, Native Americans burned chaparral to promote grasslands for textiles and food. Though adapted to infrequent fires, chaparral plant communities can be exterminated by frequent fires especially with climate change induced drought. Today, frequent accidental ignitions can convert chaparral from a native shrubland to nonnative annual grassland and drastically reduce species diversity, especially under global-change-type drought. The historical fire return interval for chaparral communities used to be 30–50 years, but has now decreased to 5–10 years due to human interference.

Human influence

The region has been heavily affected by grazing, logging, dams and water diversions, and

intensive agriculture Intensive agriculture, also known as intensive farming (as opposed to extensive farming), conventional, or industrial agriculture, is a type of agriculture, both of crop plants and of animals, with higher levels of input and output per unit of ag ...

and urbanization, as well as competition by numerous introduced or exotic plant and animal species. Some unique plant communities, like southern California's

Coastal Sage Scrub Coastal sage scrub, also known as coastal scrub, CSS, or soft chaparral, is a low scrubland plant community of the California coastal sage and chaparral subecoregion, found in coastal California and northwestern coastal Baja California. It is ...

, have been nearly eradicated by agriculture and urbanization. As a result, the region now has many rare and endangered species, including the California condor (''Gymnogyps californianus'').

References

* Bakker, Elna (1971) ''An Island Called California.'' University of California Press; Berkeley. * Dallman, Peter R. (1998). ''Plant Life in the World's Mediterranean Climates.'' California Native Plant Society–University of California Press; Berkeley. * Ricketts, Taylor H; Eric Dinerstein; David M. Olson; Colby J. Loucks; et al. (1999). ''Terrestrial Ecoregions of North America: a Conservation Assessment.'' Island Press;

Washington, DC ) , image_skyline = , image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morg ...

. * Schoenherr, Allan A. (1992). ''

A Natural History of California Allan A. Schoenherr (February 6, 1937 – May 31, 2021) was a Californian author, ecologist, and naturalist. He is the author of the widely used reference book, '' A Natural History of California''. He received his PhD in zoology at Arizona Stat ...

.'' University of California Press; Berkeley.

External links

{{commons and category
World Wildlife Fund: California Chaparral and Woodlands ecoregionCalifornia Chaparral Institute website
( ttp://www.cas.vanderbilt.edu/bioimages/ecoregions/51201.htm slow modem version
California Interior Chaparral and Woodlands images at bioimages.vanderbilt.edu
—

— ( ttp://www.cas.vanderbilt.edu/bioimages/ecoregions/51203.htm slow modem version Mediterranean forests, woodlands, and scrub Mediterranean forests, woodlands, and scrub in the United States Ecoregions of California Ecoregions of Mexico *01 Forests of California Natural history of Baja California Plant communities of California Nearctic ecoregions Sclerophyll forests