one of the most biologically diverse arid regions in the world.It is also one of the most endangered.
desert is bounded to the east and west by the ranges of the Sierra Madre Oriental and the Sierra Madre Occidental
Typically, the basins are internally drained,resulting in the formation of saline ephemeral lakes known as playas.Dune fields, composed of quartz or gypsum sand,are common throughout the desert,while volcanic
creosote Larrea tridentata
tarbush (Flourencia cernia
lechuguilla (Agavelechuguilla), is considered the primary diagnostic species of the Chihuahuan Desert
Spanish ranchers and,later,American settlers were drawn to the Chihuahuan Desert region bythe lush grasslands and potential for grazing.Once,grasses in the Big Bend region of Texas were said to have been tall enough to brush the bellies of horses.Ranchers believed that the supply of grass to feed livestock was unlimited.By the mid-19th century,the stocking of desert grassland ranges with cattle, sheep,and goats was progressing at a phenomenal rate. In 1900,the desert grasslands of west Texas supported over 9 million herd animals, up from 500,000 head in 1830
thousands of acres of Chihuahuan Desert grasslands were converted to desert shrubland, a process that continues to this day 
Chihuahuan Desert is punctuated bylarge lake basins and crisscrossed bydrainages?indicators of a time thousands of years ago when water was more plentiful and lakes and flowing rivers wereabundant.With climatic warming and drying over the past 10,000 years [man did this by reducing groundcover increasing evaporation]
[the next caption] Some desert grasslands have survived overgrazing [b b but climate change]
replacement of diverse riparian forests with monocultures of tamarix (Tamarix spp.), an invasive tree introduced in the 1800s
entire range of a particular cactus species may be confined to a single rock outcrop,
Chihuahuan Desert Research Institute (CDRI) are devoted to promoting an awareness of the desert through research and education.Founded in 1973,the CDRI encourages student research through scholarships and the W.Frank Blair Student Paper competition,maintains a regional research library,and serves as a clearinghouse for information
CDRI?s 507-acre (205-hectare) site.Here,visitors can participate in seminars or stroll through the 20-acre (8-ha) arboretum,where over 100 species
Winter temperatures are cool, and summer temperatures are extremely hot. Most of the area receives less than 10 inches of rainfall yearly.While some winter rain falls, most precipitation occurs during the summer months.
Ephedra viridis ? mormon tea
White-thorn Acacia, Allthorn and Ocotillo are other large, conspicuous plants of the Chihuahuan Desert.