Madrean pine-oak woodlands
Encyclopedia
The Madrean pine-oak woodlands are subtropical woodland
s found in the mountains of Mexico
and the southwestern United States
.
The Madrean pine-oak woodlands are found at higher elevations in Mexico's major mountain ranges, the Sierra Madre Occidental
, the Sierra Madre Oriental
, the Trans-Mexican volcanic belt
, the Sierra Madre del Sur
, the Sierra Madre de Oaxaca
, the Peninsular Ranges
of the Baja California Peninsula
, and there are also approximately 27 enclaves in southern Arizona
and New Mexico
and in western Texas
, where they are known as the "Madrean sky islands
".
The major Madrean "sky island" ranges in Arizona are the Dragoon Mountains
, Chiricahua Mountains
, Pinaleño Mountains
, Santa Catalina Mountains
, Rincon Mountains
, Santa Rita Mountains
and Tumacacori Highlands. In New Mexico the Sacramento Mountains
and Guadalupe Mountains
which extend into Texas, as well as, the Davis Mountains
and Chisos Mountains
are also forested sky islands.
Conservation International
estimates the woodlands' original area at 461,265 km². The woodlands are surrounded at lower elevations by other ecoregion
s, mostly tropical and subtropical deserts and xeric shrublands
, forests, and grassland
s. Woodland areas were isolated from one another and from the pine-oak woodlands of the Sierra Madre Occidental to the south by the warming and drying of the climate since the ice ages.
The pine-oak woodlands are composed of stands of oak
(Quercus), pine
(Pinus), douglas-fir
(Pseudotsuga) and fir
(Abies). The trees generally occur in mixed stands, though monospecific stands are sometimes found. The pine-oak woodlands are home to one-quarter of Mexico's plant species, and Mexico is home to 44 of the 110 species of pine and over 135 species of oak, over 30 percent of the world's oak species. Plant species derived from Madrean ancestors, known as the Madro-Tertiary flora, are an important element of the California chaparral and woodlands
ecoregion.
The World Wildlife Fund recognizes several distinct pine-oak woodlands ecoregions, based on geographic distribution and species mix.
Woodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
s found in the mountains 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...
and the southwestern United States
Southwestern United States
The Southwestern United States is a region defined in different ways by different sources. Broad definitions include nearly a quarter of the United States, including Arizona, California, Colorado, Nevada, New Mexico, Oklahoma, Texas and Utah...
.
The Madrean pine-oak woodlands are found at higher elevations in Mexico's major mountain ranges, the Sierra Madre Occidental
Sierra Madre Occidental
The Sierra Madre Occidental is a mountain range in western Mexico.-Setting:The range runs north to south, from just south of the Sonora–Arizona border southeast through eastern Sonora, western Chihuahua, Sinaloa, Durango, Zacatecas, Nayarit, Jalisco, Aguascalientes to Guanajuato, where it joins...
, the Sierra Madre Oriental
Sierra Madre Oriental
The Sierra Madre Oriental is a mountain range in northeastern Mexico.-Setting:Spanning the Sierra Madre Oriental runs from Coahuila south through Nuevo León, southwest Tamaulipas, San Luis Potosí, Querétaro, and Hidalgo to northern Puebla, where it joins with the east-west running Eje Volcánico...
, the Trans-Mexican volcanic belt
Trans-Mexican volcanic belt
The Trans-Mexican Volcanic Belt also known as the Transvolcanic Belt and locally as the Sierra Nevada , is a volcanic belt that extends 900 km from west to east across central-southern Mexico...
, the Sierra Madre del Sur
Sierra Madre del Sur
The Sierra Madre del Sur is a mountain range in southern Mexico, extending from southern Michoacán east through Guerrero, to the Istmo de Tehuantepec in eastern Oaxaca.-Geography:...
, the Sierra Madre de Oaxaca
Sierra Madre de Oaxaca
The Sierra Madre de Oaxaca is a mountain range in southern Mexico. It begins at Pico de Orizaba and extends in a southeasterly direction for 300 km until reaching the Isthmus of Tehuantepec...
, the Peninsular Ranges
Peninsular Ranges
The Peninsular Ranges are a group of mountain ranges, in the Pacific Coast Ranges, which stretch from southern California in the United States to the southern tip of Mexico's Baja California peninsula; they are part of the North American Coast Ranges that run along the Pacific coast from Alaska...
of the 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...
, and there are also approximately 27 enclaves in southern Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
and New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
and in western Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
, where they are known as the "Madrean sky islands
Madrean sky islands
The Madrean Sky Islands are enclaves of Madrean pine-oak woodlands, found at higher elevations in a complex of small mountain ranges in southern and southeastern Arizona, southwestern New Mexico, and northwestern Mexico. The sky islands are surrounded at lower elevations by the Sonoran and...
".
The major Madrean "sky island" ranges in Arizona are the Dragoon Mountains
Dragoon Mountains
Dragoon Mountains are a range of mountains located in Cochise County, Arizona. The range is about 25 mi long, running on an axis extending south-south east through Willcox.- Geography :...
, Chiricahua Mountains
Chiricahua Mountains
The Chiricahua Mountains are a mountain range in southeastern Arizona which are part of the Basin and Range province of the southwest, and part of the Coronado National Forest...
, Pinaleño Mountains
Pinaleno Mountains
The Pinaleño Mountains, or the Pinal Mountains, are a remote mountain range in southeastern Arizona. They have over of vertical relief, more than any other range in the state. The mountains are surrounded by the Sonoran-Chihuahuan Desert. Subalpine forests cover the higher elevations...
, Santa Catalina Mountains
Santa Catalina Mountains
The Santa Catalina Mountains, commonly referred to as the Catalina Mountains, are located north, and northeast of Tucson, Arizona, United States, on Tucson's north perimeter. The mountain range is the most prominent in the Tucson area, with the highest average elevation...
, Rincon Mountains
Rincon Mountains
The Rincon Mountains are a significant mountain range east of Tucson, Pima County, Arizona, in the United States. The Rincon Mountains are one of five mountain ranges surrounding the Tucson valley...
, Santa Rita Mountains
Santa Rita Mountains
The Santa Rita Mountains, located about 65 km southeast of Tucson, Arizona, extend 42 km from north to south, then trending southeast. They merge again southeastwards into the Patagonia Mountains, trending northwest by southeast...
and Tumacacori Highlands. In New Mexico the Sacramento Mountains
Sacramento Mountains
The Sacramento Mountains are a mountain range in the south-central part of the U.S. state of New Mexico, lying just east of Alamogordo in Otero County...
and Guadalupe Mountains
Guadalupe Mountains
The Guadalupe Mountains are a mountain range located in West Texas and southeastern New Mexico. The range includes the highest summit in Texas, Guadalupe Peak, , and the "signature peak" of West Texas, El Capitan, both located within Guadalupe Mountains National Park, as well as Carlsbad Caverns...
which extend into Texas, as well as, the Davis Mountains
Davis Mountains
The Davis Mountains are a range of mountains in West Texas, located near Fort Davis, after which they are named. They are a popular site for camping and hiking and the region includes Fort Davis National Historic Site and Davis Mountains State Park...
and Chisos Mountains
Chisos Mountains
The Chisos Mountains are a mountain range located in the Big Bend area of West Texas, USA. The mountain range is contained entirely within the boundaries of Big Bend National Park. This is the only mountain range in the United States to be fully contained within the boundary of a National Park...
are also forested sky islands.
Conservation International
Conservation International
Conservation International is a nonprofit organization headquartered in Arlington, Virginia, which seeks to ensure the health of humanity by protecting Earth's ecosystems and biodiversity. CI’s work focuses on six key initiatives that affect human well-being: climate, food security, freshwater...
estimates the woodlands' original area at 461,265 km². The woodlands are surrounded at lower elevations by other ecoregion
Ecoregion
An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...
s, mostly tropical and subtropical deserts and xeric shrublands
Deserts and xeric shrublands
Deserts and xeric shrublands is a biome characterized by, relating to, or requiring only a small amount of moisture.-Definition and occurrence:...
, forests, and grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
s. Woodland areas were isolated from one another and from the pine-oak woodlands of the Sierra Madre Occidental to the south by the warming and drying of the climate since the ice ages.
The pine-oak woodlands are composed of stands of oak
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
(Quercus), pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...
(Pinus), douglas-fir
Douglas-fir
Douglas-fir is one of the English common names for evergreen coniferous trees of the genus Pseudotsuga in the family Pinaceae. Other common names include Douglas tree, and Oregon pine. There are five species, two in western North America, one in Mexico, and two in eastern Asia...
(Pseudotsuga) and fir
Fir
Firs are a genus of 48–55 species of evergreen conifers in the family Pinaceae. They are found through much of North and Central America, Europe, Asia, and North Africa, occurring in mountains over most of the range...
(Abies). The trees generally occur in mixed stands, though monospecific stands are sometimes found. The pine-oak woodlands are home to one-quarter of Mexico's plant species, and Mexico is home to 44 of the 110 species of pine and over 135 species of oak, over 30 percent of the world's oak species. Plant species derived from Madrean ancestors, known as the Madro-Tertiary flora, are an important element 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.
The World Wildlife Fund recognizes several distinct pine-oak woodlands ecoregions, based on geographic distribution and species mix.
- Sierra Juárez and San Pedro Mártir pine-oak forestsSierra Juarez and San Pedro Martir pine-oak forestsThe 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...
of the Sierra de JuárezSierra de JuárezSierra 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....
and Sierra de San Pedro Mártir ranges of the northern Baja California peninsulaBaja California PeninsulaThe 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...
. - Sierra de la Laguna pine-oak forestsSierra de la Laguna pine-oak forestsThe 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:...
of the Sierra de la LagunaSierra de la LagunaThe 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....
in the southern Baja California peninsula. - Sierra Madre Occidental pine-oak forestsSierra Madre Occidental pine-oak forestsThe Sierra Madre Occidental pine-oak forests are a subtropical coniferous forest ecoregion of the Sierra Madre Occidental range of western Mexico and the southwestern United States...
extend along the Sierra Madre Occidental range from the Rio Grande de SantiagoRío Grande de SantiagoThe Río Grande de Santiago is one of the longest rivers in Mexico, measuring up long. The river begins at Lake Chapala and continues roughly north-west through the Sierra Madre Occidental, receiving the Verde, Juchipila, Bolaños, and other tributaries...
in Mexico's JaliscoJaliscoJalisco officially Estado Libre y Soberano de Jalisco is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is located in Western Mexico and divided in 125 municipalities and its capital city is Guadalajara.It is one of the more important states...
state through NayaritNayaritNayarit officially Estado Libre y Soberano de Nayarit is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 20 municipalities and its capital city is Tepic.It is located in Western Mexico...
, SinaloaSinaloaSinaloa officially Estado Libre y Soberano de Sinaloa is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 18 municipalities and its capital city is Culiacán Rosales....
, DurangoDurangoDurango officially Estado Libre y Soberano de Durango is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. The state is located in Northwest Mexico. With a population of 1,632,934, it has Mexico's second-lowest population density, after Baja...
, SonoraSonoraSonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....
, and Chihuahua, and include the Madrean Sky Islands of Arizona and New Mexico. - Sierra Madre Oriental pine-oak forestsSierra Madre Oriental pine-oak forestsThe Sierra Madre Oriental pine-oak forests are a subtropical coniferous forest ecoregion of northeastern and Central Mexico, extending into the state of Texas in the United States.-Setting:...
extend along the Sierra Madre Oriental ranges of Texas and Mexico, from mountaintop enclaves in west TexasTexasTexas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
through CoahuilaCoahuilaCoahuila, formally Coahuila de Zaragoza , officially Estado Libre y Soberano de Coahuila de Zaragoza is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico...
, TamaulipasTamaulipasTamaulipas officially Estado Libre y Soberano de Tamaulipas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 43 municipalities and its capital city is Ciudad Victoria. The capital city was named after Guadalupe Victoria, the...
, Nuevo LeónNuevo LeónNuevo León It is located in Northeastern Mexico. It is bordered by the states of Tamaulipas to the north and east, San Luis Potosí to the south, and Coahuila to the west. To the north, Nuevo León has a 15 kilometer stretch of the U.S.-Mexico border adjacent to the U.S...
, San Luis PotosíSan Luis PotosíSan Luis Potosí officially Estado Libre y Soberano de San Luis Potosí is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 58 municipalities and its capital city is San Luis Potosí....
, QuerétaroQuerétaroQuerétaro officially Estado Libre y Soberano de Querétaro de Arteaga is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 18 municipalities and its capital city is Santiago de Querétaro....
and GuanajuatoGuanajuatoGuanajuato officially Estado Libre y Soberano de Guanajuato is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 46 municipalities and its capital city is Guanajuato....
. - Trans-Mexican Volcanic Belt pine-oak forestsTrans-Mexican Volcanic Belt pine-oak forestsThe Trans-Mexican Volcanic Belt pine-oak forests is a subtropical coniferous forest ecoregion of the Trans-Mexican Volcanic Belt of central Mexico.-Setting:...
- Sierra Madre del Sur pine-oak forestsSierra Madre del Sur pine-oak forestsThe Sierra Madre del Sur pine-oak forests is a subtropical coniferous forest ecoregion of the Sierra Madre del Sur mountain range of southern Mexico.-Setting:...
- Sierra Madre de Oaxaca pine-oak forestsSierra Madre de Oaxaca pine-oak forestsThe Sierra Madre de Oaxaca pine-oak forests is an ecoregion of southern Mexico, in the Tropical and subtropical coniferous forests biome. It occupies the Sierra Madre de Oaxaca, which lies mostly within the state of Oaxaca, extending north into Puebla and Veracruz states...
External links
- Madrean Pine-Oak Woodlands (Conservation International)
- Sierra Juarez and San Pedro Martir pine-oak forests (World Wildlife Fund)
- Sierra de la Laguna pine-oak forests (World Wildlife Fund)
- Sierra Madre Occidental pine-oak woodlands (World Wildlife Fund)
- Sierra Madre Oriental pine-oak forests (World Wildlife Fund)
- Sierra Madre Occidental Pine-Oak Forests images at bioimages.vanderbilt.edu (slow modem version)
- Trans-Mexican Volcanic Belt pine-oak forests (World Wildlife Fund)
- Sierra Madre del Sur pine-oak forests (World Wildlife Fund)
- Sierra Madre de Oaxaca pine-oak forests (World Wildlife Fund)