Sierra del Burro

The Sierra del Burro (also called Serranias del Burro) is the northernmost finger of the Sierra Madre Oriental in the state of Coahuila, Mexico. The Sierra begins at the Rio Grande near Big Bend National Park in Texas and extends southeast for about 70 miles (110 km), reaching a maximum elevation of 6,701 feet (2,042 m).

The Sierra del Burro increases in altitude and width as it goes from north to south. At its northernmost point near the Rio Grande, the Sierra is about 15 miles (24 km) wide and has a maximum elevation of about 3,000 feet (910 m). At its southernmost extremity, about 28’ 30° North latitude, it reaches a width of more than 40 miles (64 km) and a maximum altitude of 6,701 feet (2,042 m). There is no clearly defined southern limit to the Sierra del Burro, as it merges with the Sierra del Carmen and becomes known as the Sierra Madre Oriental.

The Rio San Rodrigo is the largest river originating in the Sierra del Burro. The drainage from the Sierra is to the Rio Grande. The Sierra is located in the Chihuahua Desert, and most of the vegetation is arid or semi-arid desert scrub, including chaparral and Tamaulipan matorral. Oak forests are found, mostly at elevations of more than 4,900 feet (1,500 m). Among the fauna are the American black bear, an endangered species in Mexico, except for the Sierra del Burro where it is still found in fair numbers, but considered at risk. Beaver are also found in the Sierra. Due to its proximity the flora and fauna have similarities to that of the Big Bend region of Texas.

Precipitation in the Sierra ranges from 10 to 20 inches (250 to 510 mm). Most precipitation comes in the summer. The Sierra del Burro has been recognized by satellite photography as being an area of high supercell activity in summer, which translates into strong thunderstorms and possible tornados. There are no towns or cities or any paved roads in the Sierra. The sparse population mostly inhabits large ranches.

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Wikipedia