Taken from a western bajada of the San Andres Mountains in southern New Mexico, this image looks northwest over the W Spear Bar Ranch in the Jornada del Muerto, and shows a broad expanse of Chihuahuan Desert grassland invaded by creosote bush. The vegetation in the left half of the image was chemically treated with tebuthiuron by the BLM through its Restore New Mexico program. Increased production of perennial grasses in the treated area results from reduced competition from the creosote bush.
Gravels and rocks that predominantly cover the soil surface stabilize the soil surface and reduce the potential for erosion by both wind and water.
The color change from yellow to green demarcates the transition zone between treated and untreated areas. In the treated area on the left, vegetation was chemically treated with tebuthiuron to control creosotebush.
Creosotebush (Larrea tridentata) is a clonal, multi-stemmed, evergreen shrub that is native to the hot deserts of the southwestern US and northern Mexico. This species is abundant on sandy and gravelly soils, and has successfully invaded former grasslands throughout this region.
Ocotillo (Fouquieria splendens) is a large shrub with multiple, unbranched stems armed with long thorns. The shrubs are common on dry slopes and mesas, and tend to proliferate on limy slopes.
Ocotillo is drought deciduous shrub, capable of producing several sets of leaves throughout a single growing season. Leaves are produced when moisture conditions are favorable; the plant sheds its leaves when soil moisture become limiting, but will produce a subsequent set of leaves following rains that replenish soil moisture. Although the green striations in the bark contain chloroplasts and chlorophyll, stem photosynthesis has not been observed in this species.