Edwards Plateau

The Edwards Plateau is a region of west-central Texas which is bounded by the Balcones Fault to the south and east, the Llano Uplift and the Llano Estacado to the north, and the Pecos River and Chihuahuan Desert to the west^[1]. San Angelo, Austin, San Antonio and Del Rio roughly outline the area.

Counties in the Edwards Plateau

According to the Texas Parks and Wildlife Department, the following 40 counties comprise the Edwards Plateau: ^[2]

Geology and natural history

The bedrock consists primarily of limestone, with elevations ranging between 100 ft. and 3000 ft. Caves and springs (in wet years) are numerous. The Plateau mostly lacks deep soil suitable for farming, though some cotton, grain sorghum and oats are grown. Thin soil and rough terrain areas are primarily grazing regions, with cattle, sheep and Angora goats predominant^[3]. Several rivers cross the region, which generally flow to the south and east through the Texas Hill Country toward the Gulf of Mexico; however, permanent surface water supplies are sparse throughout the area, except for man-made reservoirs. The area is well drained; rainwater flows into the Edwards Aquifer recharge zone at the south of the plateau to feed rivers to the south. Rainfall varies from 15 to 33 in. per year, on average, from northwest to southeast.

The Balcones Fault is associated with the Edwards Plateau formation.^[4] This fault line is an ecological demarcation for the range definition of a number of species. For example, the California Fan Palm, Washingtonia filifera, is known to occur only west of the Edwards Plateau or Balcones Fault.

Human history

Earliest human settlement of this are was by Native Americans.^[5] First it was used and wandered about by Jumano and Coahuiltecan groups, than after the Apacheria extends into the Southern Plains by the forrunners of the Lipan and Mescalero Apaches. After the expulsion of the Apachean groups from the Plains by the Comanche, this area was dominated by the Penateka band of the Southern Comanche.:P

See also

• Texas Hill Country
• Balcones Canyonlands National Wildlife Refuge
• Colorado River (Texas)
• Mount Bonnell

Footnotes

1. ^ Demarest, D. "Edwards Plateau". Partners in Flight. http://www.blm.gov/wildlife/pl_53sum.htm. Retrieved 12 March 2009.
2. ^ Texas Parks and Wildlife http://www.tpwd.state.tx.us/huntwild/wild/birding/pif/assist/pif_regions/region_7.phtml
3. ^ Johnson, E.H. "Edwards Plateau". Handbook of Texas Online. http://www.tshaonline.org/handbook/online/articles/EE/rxe1.html. Retrieved 12 March 2009.
4. ^ Hill, Robert T. (1891). "A brief description of the Cretaceous rocks of Texas and their economic uses". in E. T. Dumble. First Annual Report of the Geological Survey of Texas, 1889. Austin: State Printing Office. p. 134. http://www.lib.utexas.edu/books/landscapes/publications/txu-oclc-5235917-1/txu-oclc-5235917-1-b134a.html.
5. ^ Maria de Fátima Wade. 2003. The Native Americans of the Texas Edwards Plateau, 1582-1799, University of Texas Press, 293 pages ISBN 0292791569, 9780292791565

External links

• Edwards Plateau from the Handbook of Texas Online

Coordinates: 30°18′N 99°36′W / 30.3°N 99.6°W

Categories: Regions of Texas | Plateaus of the United States | Temperate grasslands, savannas, and shrublands | Landforms of Texas | Geography of Texas | Grasslands of the United States | Physiographic sections | Texas geography stubs