Just as the desert is not necessarily the desolate plane of endless sand it is portrayed to be, America's Southwest desert plants are anything but dull. Many of them have unusual characteristics that set them apart. Some pertain to their physical appearance, and others to their behavioral or growth patterns and their uses as first discovered by Native Americans.
Fooling The Four O'Clock
The showy four o'clock is a perennial plant of the Southwest whose beautiful, clustered magenta flowers earned it the Latin name, Mirabilis multiflora, meaning "Marvelous many-flowered." Instead of petals, these flowers have sepals that form a funnel-shaped bloom. The showy four o'clock does indeed bloom in the late afternoon, as its name suggests, and remains open during the night. However, cloudy weather fools these flowers into opening in the morning instead, because cloudy conditions mimic late afternoon light. The Mirabilis genus has about 60 species, all members of the Nyctaginaceae family, which includes about 250 species.
The night-blooming cereus ((Cereus greggii) is a member of the cactus family. Another common name is Queen of the Night, for the single night in June or July when this otherwise nondescript bush bursts forth in fragrant, white trumpet-shaped blooms. The flowers last for just the few hours until dawn, when they are spent with the first rays of the sun. The night-blooming cereus grows in Arizona and western Texas.
The elephant tree (Bursera microphylla) is so named not for its size but for its short and tapering trunks and branches, which look like the trunks and legs of elephants. This tree is rare and grows to a height of just 10 feet, exhibiting small, creamy-white summer flowers and red fruit in the fall. Botanists confirmed its existence only in 1937, although Native Americans derived potent medicines from this plant from earliest times. The elephant tree is native to Arizona's Sonoran Desert and southern California.
Smoke Screen Twigs
The smoke tree (Dalea spinosa) grows in the southern Nevada desert, southeastern California and western Arizona. Its name is derived from the effect of its golden, plumelike appearance of spiny branches and twigs. Clusters of dark purple flowers bloom in the spring and early summer on this 20-foot tree. Stalkless gray and hairy leaves last for just several weeks before the flowering period. The lack of leaves means that the twigs are left to create most of the food required by the smoke tree through photosynthesis. The smoke tree is a member of the Fabaceae family.
Big sagebrush (Artemisia tridentate) is a perennial shrub that grows at elevations between 4,000 and 10,000 feet in desert shrub or woodland habitats. It bears clusters of small yellow or cream-colored flowers in the summer and has the capacity to produce up to 1 million seeds. Native Americans used the wood of this plant for fuel or to build homes and ate the seeds and leaves. Because they contain camphor, the leaves had medicinal uses. Big sagebrush is the state plant of Nevada.