Saturday

Creosote Bush (Larrea tridentata)

EFP-P1020423
(Fig. 01)
Picture Notes: The picture in (Fig. 01) was taken while hiking in the Joshua Tree Wilderness Area off of Nipton Road,west of Searchlight, NV. The pictures showing the Creosote Bush during its flowering period (Figs. 02 & 03) were captured while hiking the Old Spanish Trail route as it passes through Cottonwood Valley on the south side of NV-160.
            
Description: Creosote Bush (Larrea tridentata), a.k.a. Little Stinker, greasewood and Chaparral,  is a perennial evergreen shrub growing to 3.3 to 9.8 feet tall, and rarely to 13 feet where there is heavy rain. The stems of the plant bear resinous, small dark green leaves with two opposite lanceolate leaflets joined at the base, with a deciduous awn between them, each leaflet 0.28 to 0.71 inches long and 0.16 to 0.33 inches broad. The leaf color, often shiny with wax, depends on season (water): leaves are dark green to yellowish green during spring when water is available, but they turn brown during summer or when water is not available.The flowers are up to 0.98 inches in diameter, with five solitary yellow petals. Fruit is a white, fuzzy, ball about 0.25 inches in size.The plant blooms when water is available, usually in the spring after winter rains and during summer after thunderstorms.Galls may form by the activity of the creosote gall midge. The whole plant exhibits a characteristic odor of creosote, hence its common name.
The Creosote Bush is one of the signature plants in the Sonoran, Chihuahuan, and Mojave Deserts. It is most common on the well-drained soils of alluvial fans and flats in elevations up to about 4,500 feet. In parts of its range, it may cover large areas in practically pure stands, though it usually occurs in association with Ambrosia dumosa (burro bush or bur-sage). It has been shown that the root systems of mature creosote plants are simply so efficient at absorbing water, that fallen seeds nearby cannot accumulate enough water to germinate, effectively creating dead zones around every plant. It also seems that all plants within a stand grow at approximately the same rate, and that the creosote bush is a very long-living plant. Right at the end of the last ice age about 11,000 years ago, an individual creosote bush began growing, and it is still growing today!! This would make it the oldest individual on Earth. Creosote Bushes grow in ever-widening circles, with their center bushes dying out and sprouting new bushes to the outside (thus no one twig is 11,000 years old). They are so good at soaking up water, that after localized heavy thunderstorms, you will see patches or bands of bright green creosote bush stretching out across the landscape where it rained, while the surrounding landscape remains brown. It is thought to be the most drought-tolerant plant in the desert and can go without rain for at least two years, and survive in areas receiving only 3" of rain per year on average.
          
EFP-P1110393
(Fig. 02)
EFP-P1110389
(Fig. 03)