El Paso, Texas Soil and Plant Information

Igneous Soils

• In the southwestern part of the city, The University of Texas at El Paso and its Sun Bowl Stadium are built on fine gravelly soils that were degraded, or broken down, from outcrops of andesite and syenite igneous rocks, the remains of volcanic intrusions that did not erupt onto the surface. In some areas, the gravels support creosote and range ratany shrubs. Creosote is a shrub, about 5 feet in height, with small, sticky, aromatic leaves and yellow flowers. Range ratany is a smaller shrub, about 18 inches high, with gray-green fuzzy leaves and purple flowers that offer bees oil instead of nectar. Range ratany photosynthesizes and is also a root parasite of creosote.

Limestone Soils

• Various limestone soils underlain by caliche can be found throughout urban El Paso. On an inter-mountain basin on the north, suburban residential communities are built on Turney-Berino soils, which are alkaline, light reddish-brown to brown, fine sandy loams over clay loams and caliche. These native grassland soils are suitable for irrigated corn and sorghum. Fifty percent of the 63,700-acre Delnorte-Canutio soils are inside the city. Their pinkish-gray, 6-inch, gravelly loam surface layer is underlain by 24 inches of strongly-cemented caliche and can support creosote shrub.

Badlands

• On the southeast side of the City of El Paso, the bare landscapes of 50- to 500-acre gullied, reddish-gray clay badlands support only a few stunted creosote bushes. The heavy clay is 4 to 9 feet thick and is typically stratified with layers of sandy loam 2 to 6 feet thick. The clay is rock hard and impervious to rainfall, seldom moist to more than 3 or 4 inches on the surface. These soils are found in patches along the Rio Grande River.

Native Plants

• All of El Paso County is in two vegetation zones. The Desert Shrub zone is below 4,500 feet in elevation and has less than 10 inches of annual precipitation, and the Desert Grassland zone is at slightly cooler elevations, above 4,500 feet and with more than 10 inches of precipitation. Most of the county is overgrazed, and native grassland survives only on the slopes of the Franklin Mountains, where surface water was not historically available for livestock and the grassland is now protected as recreation area.