Common Name(s): Creosote

Synonym(s):

Family: Zygophyllaceae

Native To: Throughout the warm North American deserts, from Nevada to central México, up to 1600 m (5200 ft) in elevation

Native Habitat: Semi-desert grassland, chaparral, thornscrub, desertscrub, conifer woodland

Growth Habit: Slender-branched shrub up to 3.5 meters

Flowering: Any time following rain, even in winter

Distinguishing Characteristics: Creosote is easily recognized by the tough small tough leaves, resinous when young, formed of two leaflets fused together at the base. The contrasting bright yellow flowers can appear any time a good rain occurs, followed soon by white fuzzy ball-shaped fruits which tumble along the desert floor in the wind. The thin gray stems are jointed and swollen at branching points.

Natural History and Cultivation Notes: Creosote is one of the most prominent plants in our deserts, covering thousands of square miles, often in pure stands, often with plants of equal size. Most closely related to Larrea divaricata of South America, it has been hypothesized that our creosote came up from South America before the more than 11,000 years ago, moved into the Chihuahuan desert, from there to the Sonoran Desert, then to the Mohave Desert. Creosote is very well adapted to heat and drought, surviving in places where apparently little else can. It has an extensive root system, much of it very shallow, and chemicals exuded by the roots are known to inhibit some other shrubs' roots, including creosote, which may in part explain the stands of evenly spaced plants. A slow grower, it takes at least 13 years for reproductive maturity. New stems arise from the base of the plant at the outside edge, and when old stems eventually die (after 40-90 years), a space is created in the middle. In this way, clones of single plants form rings, the largest and oldest of which are estimated to be 11,700 years old. Over 40 insects are known to be wholly or partly dependent on creosote.

Ethnobotany: Highly esteemed by Indians of the Sonoran desert, it is a shockingly useful desert plant with some truly unique qualities. The waxy coating of the leaves has historically been used to prevent oils and fats from going rancid. It also produces a resin that can be used as glue or for waterproofing. The bush is best known, however, for its medicinal properties. It has been used to relieve a host of ailments ranging from the smelly feet to infertility. A tea made from leaves is well known to soothe symptoms of the common cold such as sore throats, congestion, coughs, and fevers. It can also relieve stomach problems and regulate the bowels. A tea made from the roots can be used to cure ulcers. Other recorded medicinal uses include treatment of urinary tract infections, herpes, shingles, rheumatism, arthritis, liver and kidney problems, fertility issues, paralysis, swelling, diabetes, and even cancer and tumors! It is also a useful painkiller, sanitizer, and healing agent for wounds. Although it has an impressive list of practical uses, many prize this plant simply for the wonderful scent it emits when it is wet, known to desert-dwellers as the “smell of rain.”

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