Malpai Borderlands is a region, or areal feature, along the U.S.-Mexico border at the

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

and

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ke ...

state line. It encompasses the extreme southeast corner of Arizona and the southwest corner of New Mexico describe the general vicinity. It includes areas inside the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sove ...

s of Arizona and New Mexico as well as the Mexican states of Chihuahua and Sonora. The lowest elevations in this area are about 3,700 feet in the San Bernardino National Wildlife Refuge area. Highest elevation is roughly 8,500 feet above mean sea level (AMSL). Mountain ranges generally run north-south. Terrain is described as including desert shrub, Tobosa grassland,

Ponderosa Pine ''Pinus ponderosa'', commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is the ...

forest, and Douglas Fir. Some cattle ranching takes place in the region. The geomorphic provinces include Madrean and

Chihuahuan desert The Chihuahuan Desert ( es, Desierto de Chihuahua, ) is a desert ecoregion designation covering parts of northern Mexico and the southwestern United States. It occupies much of far West Texas, the middle to lower Rio Grande Valley and the lo ...

s. The name "Malpai", relates to a type of "

desert pavement A desert pavement, also called reg (in the western Sahara), serir (eastern Sahara), gibber (in Australia), or saï (central Asia) is a desert surface covered with closely packed, interlocking angular or rounded rock fragments of pebble and cob ...

", formed by wind ( eolian) processes, and is called Malapai.

Variant names

The Borderlands are sometimes referred to by the name of a larger region encompassing Malpai Borderlands: Southwest Borderlands. The name is sometimes misspelled ''Maipai'' Borderlands. Some references describe it as being inside the Chihuahuan Desert.

Unofficial extents of the region

Papers on the region describe geographic features that partly define it. The United States portion of this region probably includes portions of

Grant County, New Mexico Grant County is a county located in the U.S. state of New Mexico. At the 2020 census, the population was 28,185. Its county seat is Silver City. The county was founded in 1868 and named for Ulysses S. Grant, the 18th President of the United St ...

Hidalgo County, New Mexico Hidalgo County ( es, Condado de Hidalgo) is the southernmost county of the U.S. state of New Mexico. As of the 2010 census, the population was 4,894. The county seat and largest city is Lordsburg. A bill creating Hidalgo from the southern part ...

, and Cochise County, Arizona. Major geographic features of the area include portions of the San Simon, San Bernardino, Animas, and Playas valleys as well as rivers of the same name. Except for

's San Simon Valley and San Simon River, the areas mentioned appear to be entirely south of present-day Interstate 10. Government reservations in this region include all of

Coronado National Forest The Coronado National Forest is a United States National Forest that includes an area of about 1.78 million acres (7,200 km2) spread throughout mountain ranges in southeastern Arizona and southwestern New Mexico. It is located in parts of ...

(US Forest Service) east of US191 and San Bernardino National Wildlife Refuge, (US Fish and Wildlife Service). In the Mexican state of Sonora, Dieciocho de Agosto, Sierra de los Ajos (sometimes written Sierra Ajos),

Agua Prieta Agua Prieta (English: ''Dark Water'', Opata: ''Bachicuy'') is a town in Agua Prieta Municipality in the northeastern corner of the Mexican state of Sonora. It stands on the Mexico–U.S. border, adjacent to the town of Douglas, Arizona. The mu ...

, ''frontera'' (frontier), Cañón del Oso and Nogales are mentioned. In the state of Chihuahua, the area of Janos is mentioned.

Variant descriptions

A fire history report on the region suggests some definitions may include areas as far west as the Huachuca Mountains of Arizona.

Area under scientific study

A wide array of individuals and organizations are eyeing competing demands on these lands. The

US Forest Service The United States Forest Service (USFS) is an agency of the U.S. Department of Agriculture that administers the nation's 154 national forests and 20 national grasslands. The Forest Service manages of land. Major divisions of the agency inc ...

, Arizona Geological Survey,

US Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and ...

, Natural Resource Conservation Service (formerly Soil Conservation Service),

University of New Mexico The University of New Mexico (UNM; es, Universidad de Nuevo México) is a public research university in Albuquerque, New Mexico. Founded in 1889, it is the state's flagship academic institution and the largest by enrollment, with over 25,400 ...

, The Nature Conservancy, New Mexico Department of Fish and Game,

University of Arizona The University of Arizona (Arizona, U of A, UArizona, or UA) is a public land-grant research university in Tucson, Arizona. Founded in 1885 by the 13th Arizona Territorial Legislature, it was the first university in the Arizona Territory. T ...

, and

have been active in studying the future of the area.

Sources

* "Toward Integrated Research, Land Management, and Ecosystem Protection in the Malpai Borderlands: Conference Summary,"

Rocky Mountain Research Station The Rocky Mountain Research Station (RMRS) is one of five regional units that make up the US Forest Service Research and Development organization — the most extensive natural resources research organization in the world. The station headquarte ...

Report P-10,

, July 1999.
US Geological Survey web page on region

External links