Mesquite (Prosopis) is perhaps the most common leguminous plant occurring naturally in Texas. Four species occur; the variety P. glandulosa glandulosa is the most widespread, being found throughout the state. Mesquite ranges from a shrub to a tree and has thorns and pinnately twice-compound leaves. Its flowers are creamy white and turn yellow with maturity. The fruit is a leathery, solid, indehiscent pod several centimeters long. Mesquite is a sprouting plant with numerous dormant buds belowground that are activated when the aboveground portion is damaged or killed. The plant, native to Texas and the Southwest, originally grew only along streams and rivers and in open groves, but now it occupies about fifty million to sixty million acres of Texas rangelands, excluding the piney woods. The spread of mesquite within Texas can be attributed to such causes as the cessation of prairie fires, overgrazing, wagontrains traversing the state, trail drives, and drought.
Mesquite furnishes shade for livestock and habitat for wildlife. It provides food and cover for such species as quail, dove, raven, turkey, Gambel quail, mallard duck, white-tail and mule deer, wood rat, kangaroo rat, chipmunk, pocket mouse, ground squirrel, prairie dog, cottontail, jackrabbit, skunk, peccary, coyote, and Mexican raccoon. It has many varied uses throughout the Southwest. The mesquite-bean pod was a staple in the Indians' diet and was even considered a luxury by some groups. Pods were also ground into meal and made into bread or mixed with water to form a sweet, nutritious atole, which, when fermented, produced a weak beer. Honey made from the nectar of mesquite flowers is considered a delicacy. Indian women used mesquite bark to make diapers, skirts, and other articles of clothing. They wove baskets, ropes, and twine from mesquite fibers. Mesquite bark was also used to make a poultice for treating wounds and illnesses. The gum exuded from mesquite trunks was used as candy, as a glue for mending pottery, and as a black dye. Unfinished mesquite wood has been used for fenceposts and corrals. It can also be used as boiler fuel, wood chips, wood flakes, meal, feed, mulch, particleboard, insulation batting, and charcoal. The trees have been used as ornamentals in landscaping homes. The wood is very hard and has been successfully made into such articles of furniture as cabinets, game tables, and desks.
Though mesquite has been beneficial to many cultures, it is also a menace because of the amount of water it uses. Sparse stands do not deplete soil water drastically, but dense stands growing along streams and rivers, above shallow water tables, and in deep soil use water extravagantly. In addition to reducing the amount of water that ultimately could be available for agricultural purposes, mesquite reduces the amount of forage available for livestock. Its presence also causes an inconvenience to ranchers working livestock. In the early 1980s mesquite became a popular fuel for cooking in restaurants all over the country. In 1979 Ranchmen's Manufacturing in Dallas, the largest producer of mesquite in the world, had fewer than 1,000 customers. By 1984 the company reported between 12,000 and 15,000. The trend may have reached its peak by that year, when mesquite was already being replaced by grapevine in California restaurants.