The Peninsular Ranges are a group of mountain ranges, in the Pacific Coast Ranges

Pacific Coast Ranges

The Pacific Coast Ranges and the Pacific Mountain System are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico...

, which stretch 1500 km (932.1 mi) from southern California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 to the southern tip of Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

's Baja California peninsula

Baja California Peninsula

The Baja California peninsula , is a peninsula in northwestern Mexico. Its land mass separates the Pacific Ocean from the Gulf of California. The Peninsula extends from Mexicali, Baja California in the north to Cabo San Lucas, Baja California Sur in the south.The total area of the Baja California...

; they are part of the North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

n Coast Ranges that run along the Pacific

Pacific Ocean

The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

 coast from Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 to Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. Elevation

Elevation

The elevation of a geographic location is its height above a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface ....

s range from 500 ft to 11,500 ft (150 m to 3,500 m).

Geography

The Peninsular Ranges include the Santa Ana Mountains

Santa Ana Mountains

The Santa Ana Mountains are a short peninsular mountain range along the coast of Southern California in the United States. They extend for approximately 36 mi southeast of the Los Angeles Basin largely along the border between Orange and Riverside counties.- Geography :The range starts in the...

, San Jacinto Mountains

San Jacinto Mountains

The San Jacinto Mountains are a mountain range east of Los Angeles in southern California in the United States. The mountains are named for Saint Hyacinth . The Pacific Crest Trail runs along the spine of the range.The range extends for approximately from the San Bernardino Mountains southeast to...

 and Laguna Mountains

Laguna Mountains

The Laguna Mountains are a section of the Peninsular Ranges in eastern San Diego County, California. The mountains run in a northwest/southeast alignment for approximately ....

 of southern California with the Sierra Juarez

Sierra Juárez

Sierra de Juárez is a mountain range on the Baja California Peninsula, of Baja California, Mexico. It is part of the Peninsular Ranges. The Laguna Mountains of California lie to the north and the Sierra San Pedro Mártir lies to the south....

, Sierra San Pedro Mártir

Sierra San Pedro Mártir

Sierra de San Pedro Mártir is a mountain range that is one of the Peninsular Ranges of the Baja California peninsula, Mexico. At , the highest peak is the Picacho del Diablo, also known as Cerro de la Encantada or Picacho la Providencia...

, Sierra de la Giganta

Sierra de la Giganta

The Sierra de la Giganta is a mountain range of Baja California Sur state in northwestern Mexico. The range extends parallel to the coast of the Gulf of California, west of the town of Loreto. The Sierra de la Giganta is one of the landforms in the Peninsular Ranges, which extend from Southern...

, and Sierra de la Laguna

Sierra de la Laguna

The Sierra de la Laguna is a mountain range on the Baja California Peninsula of Mexico. It lies at the southern end of the peninsula in the state of Baja California Sur, and is the southernmost range of the Peninsular Ranges....

 of Baja California. Palomar Mountain

Palomar Mountain

Palomar Mountain is a mountain in the Peninsular Ranges in northern San Diego County. It is famous as the location of the Palomar Observatory and Hale Telescope, and known for the Palomar Mountain State Park.-History:...

, home to Palomar Observatory

Palomar Observatory

Palomar Observatory is a privately owned observatory located in San Diego County, California, southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. At approximately elevation, it is owned and operated by the California Institute of Technology...

, is in the Peninsular Ranges in San Diego County, as is Viejas Mountain

Viejas Mountain

Viejas Mountain is a mountain in San Diego County in the US state of California, elevation . The mountain can be seen from parts of metropolitan San Diego....

. The Peninsular ranges run predominantly north-south, unlike the Transverse Ranges

Transverse Ranges

The Transverse Ranges are a group of mountain ranges of southern California, in the Pacific Coast Ranges physiographic region that runs along the Pacific coast from Alaska to Mexico in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie between...

 to their north, which mostly run east-west.

Geology

Rocks in the ranges are dominated by Mesozoic

Mesozoic

The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

 granitic rock

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

s, derived from the same massive batholith which forms the core of the Sierra Nevada Mountains in California. They are part of a geologic province known as the Salinian Block

Salinian Block

The Salinian Block or Salinian terrane is a geologic terrane which lies west of the main trace of the San Andreas Fault system in California. It is bounded on the south by the Big Pine Fault in Ventura County, and on the west by the Nacimiento Fault...

 which broke off the North American Plate

North American Plate

The North American Plate is a tectonic plate covering most of North America, Greenland, Cuba, Bahamas, and parts of Siberia, Japan and Iceland. It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust...

 as the San Andreas Fault

San Andreas Fault

The San Andreas Fault is a continental strike-slip fault that runs a length of roughly through California in the United States. The fault's motion is right-lateral strike-slip...

 and Gulf of California

Gulf of California

The Gulf of California is a body of water that separates the Baja California Peninsula from the Mexican mainland...

 came into being.

Nearctic

Most of the Peninsular Ranges are in the Nearctic

Nearctic

The Nearctic is one of the eight terrestrial ecozones dividing the Earth's land surface.The Nearctic ecozone covers most of North America, including Greenland and the highlands of Mexico...

 ecozone

Ecozone

An ecozone is the broadest biogeographic division of the Earth's land surface, based on distributional patterns of terrestrial organisms.Ecozones delineate large areas of the Earth's surface within which organisms have been evolving in relative isolation over long periods of time, separated from...

. Several terrestrial ecoregions cover portions of the Peninsular Ranges. On western-coast side of the northern portion of the ranges the California montane chaparral and woodlands

California montane chaparral and woodlands

The California montane chaparral and woodlands ecoregion covers , including the mountains of the Transverse, Peninsular, and Santa Lucia Ranges of California. It is part of the Mediterranean forests, woodlands, and scrub biome, with cool, wet winters and hot, dry summers...

 sub-ecoregion of the California chaparral and woodlands

California chaparral and woodlands

The California chaparral and woodlands is a terrestrial ecoregion of lower northern, central, and southern California and northwestern Baja California , located on the west coast of North America...

 ecoregion covers in southern California and northern Baja California. On western-coast side of the southern portion of the ranges the Baja California desert

Baja California Desert

The Baja California Desert is a Desert ecoregion of Mexico's Baja California Peninsula.-Geography and climate:The ecoregion covers 77,700 square kilometers and includes most of the Peninsula's western slope. It is bounded on the west by the Pacific Ocean and on the east by the Peninsular Ranges...

 ecoregion covers in the southern portion of the Peninsular Ranges in Baja California and Baja California Sur

Baja California Sur

Baja California Sur , is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. Before becoming a state on October 8, 1974, the area was known as the South Territory of Baja California. It has an area of , or 3.57% of the land mass of Mexico and comprises...

. On eastern side of northern ranges, the Sonoran Desert

Sonoran Desert

The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...

 ecoregion covers southeastern California and northeastern Baja California as far south as the town of Loreto

Loreto, Baja California Sur

Loreto was the first Spanish settlement on the Baja California Peninsula. It served as the capital of Las Californias from 1697 to 1777, and is the current seat of the municipality of Loreto in the Mexican state of Baja California Sur...

, Baja California Sur

Baja California Sur

Baja California Sur , is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. Before becoming a state on October 8, 1974, the area was known as the South Territory of Baja California. It has an area of , or 3.57% of the land mass of Mexico and comprises...

. On the eastern side of the Laguna Mountains in San Diego County

San Diego County, California

San Diego County is a large county located in the southwestern corner of the US state of California. Hence, San Diego County is also located in the southwestern corner of the 48 contiguous United States. Its county seat and largest city is San Diego. Its population was about 2,813,835 in the 2000...

 the Anza-Borrego Desert State Park

Anza-Borrego Desert State Park

Anza-Borrego Desert State Park is a state park located within the Colorado Desert of Southern California. The park takes its name from 18th century, Spanish explorer Juan Bautista de Anza and borrego, the Spanish word for bighorn sheep...

 is known for its springtime profusion of Colorado Desert

Colorado Desert

California's Colorado Desert is a part of the larger Sonoran Desert, which extends across southwest North America. The Colorado Desert region encompasses approximately , reaching from the Mexican border in the south to the higher-elevation Mojave Desert in the north and from the Colorado River in...

 (Sonoran) wildflowers. On eastern-Gulf of California

Gulf of California

The Gulf of California is a body of water that separates the Baja California Peninsula from the Mexican mainland...

 side of the southern portion of the ranges the Gulf of California xeric scrub

Gulf of California xeric scrub

The Gulf of California xeric scrub is a xeric shrubland ecoregion of Mexico's Baja California Peninsula.-Setting:The Gulf of California xeric scrub covers an area of , lying on the eastern side of the peninsula along the Gulf of California, and extending to several of the islands in the gulf...

 ecoregion covers the range in Baja California Sur.

The higher portions of the Peninsular Ranges, especially the west-facing slopes, are home to coniferous and mixed evergreen forest

California mixed evergreen forest

California mixed evergreen forest is an ecoregion, of the temperate broadleaf and mixed forests biome, that occurs in the Pacific Coast Ranges of southwestern Oregon and California, and in the Coast, Transverse, and Peninsular Ranges in California...

s. Cleveland National Forest

Cleveland National Forest

Cleveland National Forest encompasses 460,000 acres , mostly of chaparral, with a few riparian areas. A warm dry mediterranean climate prevails over the Forest. It is the southernmost National forest of California. It is administered by the United States Forest Service, a government agency within...

 covers much of the higher Southern California

Southern California

Southern California is a megaregion, or megapolitan area, in the southern area of the U.S. state of California. Large urban areas include Greater Los Angeles and Greater San Diego. The urban area stretches along the coast from Ventura through the Southland and Inland Empire to San Diego...

 Peninsular Ranges. The vegetation includes oak woodland

California oak woodland

California oak woodland is a plant community found throughout the California chaparral and woodlands ecoregion of California in the United States and northwestern Baja California in Mexico...

s and forests of Jeffrey Pine (Pinus jeffreyi) and Coulter Pine (Pinus coulteri). The Sierra Juarez and San Pedro Martir pine-oak forests

Sierra Juarez and San Pedro Martir pine-oak forests

The Sierra Juárez and San Pedro Mártir pine-oak forests is an ecoregion, in the Temperate coniferous forests biome, that covers the higher elevations of the Sierra Juárez and Sierra San Pedro Mártir ranges, of the Peninsular Ranges, in the northern Baja California Peninsula of Mexico, near the...

 cover upper slopes of Sierra Juarez and San Pedro Martir ranges in Baja California. These isolated forests, predominantly Tamarack Pine (Pinus contorta subsp. murrayana)

Lodgepole Pine

Lodgepole Pine, Pinus contorta, also known as Shore Pine, is a common tree in western North America. Like all pines, it is evergreen.-Subspecies:...

, Sugar Pine (Pinus lambertiana), Parry Pinyon (Pinus quadrifolia)

Parry Pinyon

Pinus quadrifolia, the Parry Pinyon, is a pine in the pinyon pine group, native to southernmost California in the United States and northern Baja California in Mexico, from 33° 30' N south to 30° 30' N. It occurs at moderate altitudes from to , rarely as low as and as high as...

, White Fir (Abies concolor), California Incense Cedar (Calocedrus decurrens)

Calocedrus

Calocedrus is a genus of three species of coniferous trees in the cypress family Cupressaceae.The generic name means "beautiful cedar".-Description:...

, and juniper

Juniper

Junipers are coniferous plants in the genus Juniperus of the cypress family Cupressaceae. Depending on taxonomic viewpoint, there are between 50-67 species of juniper, widely distributed throughout the northern hemisphere, from the Arctic, south to tropical Africa in the Old World, and to the...

s. Oak species include Coast Live Oak (Quercus agrifolia), Engelmann Oak (Quercus engelmannii), Canyon Live Oak (Quercus chrysolepis)

Quercus chrysolepis

Quercus chrysolepis, commonly termed Canyon Live Oak, or Golden Cup Oak, is a species of evergreen oak that is found in the southwestern part of North America, notably in the California Coast Ranges. This tree is often found near creeks and drainage swales growing in moist cool microhabitats...

, and Baja Oak (Quercus peninsularis)

Quercus peninsularis

Quercus peninsularis is a species of plant in the Fagaceae family. It is an island tree endemic to Mexico.-Source:* Nixon, K. et al. 1998. . Downloaded on 23 August 2007....

. These higher portions of the Peninsular Ranges harbor many rare and endemic species.

Neotropic

Southern Baja California Sur is part of the Neotropic

Neotropic

In biogeography, the Neotropic or Neotropical zone is one of the eight terrestrial ecozones. This ecozone includes South and Central America, the Mexican lowlands, the Caribbean islands, and southern Florida, because these regions share a large number of plant and animal groups.It is sometimes used...

 ecozone

Ecozone

An ecozone is the broadest biogeographic division of the Earth's land surface, based on distributional patterns of terrestrial organisms.Ecozones delineate large areas of the Earth's surface within which organisms have been evolving in relative isolation over long periods of time, separated from...

. The southern end of the Baja California Peninsula, including the Sierra de la Laguna

Sierra de la Laguna

The Sierra de la Laguna is a mountain range on the Baja California Peninsula of Mexico. It lies at the southern end of the peninsula in the state of Baja California Sur, and is the southernmost range of the Peninsular Ranges....

 Peninsular Range, was formerly an island, and evolved in relative isolation from the northern part of the peninsula and ranges. Its flora and fauna share many affinities with southern Mexico and Central America

Central America

Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

. It includes three distinct ecoregions, the Sierra de la Laguna dry forests

Sierra de la Laguna dry forests

The Sierra de la Laguna dry forests are a subtropical dry forest ecoregion of the southern Baja California Peninsula in Mexico.-Location:The dry forests cover the lower elevations of the Sierra de la Laguna, from elevation. They are surrounded at lower elevations by the San Lucan xeric scrub,...

, Sierra de la Laguna pine-oak forests

Sierra de la Laguna pine-oak forests

The Sierra de la Laguna pine-oak forests is a subtropical coniferous forest ecoregion, found in the Sierra de la Laguna range at the southern tip of the Baja California Peninsula, in the state of Baja California Sur of Mexico.-Setting:...

, and San Lucan xeric scrub

San Lucan xeric scrub

The San Lucan xeric scrub is a xeric shrubland ecoregion of Mexico's Baja California Peninsula.-Setting:The San Lucan xeric scrub covers an area of at the southern tip of the peninsula. The xeric scrub extends from coast up to 250 meters elevation, where the Sierra de la Laguna dry forests...

.