Vegetation and soil change following creosotebush (Larrea tridentata) control in the Chihuahuan Desert

Change in vegetation and edaphic properties as influenced by chemical creosotebush control were examined in the Chihuahuan desert of southern New Mexico. From 1981 to 2001, under a program administered by Bureau of Land Management, tebuthiuron herbicide was applied by aircraft to 67 distinct land areas. Treatments provided on average 85% creosotebush mortality and reduced canopy cover by about 95%. Grass cover increased after creosotebush removal and the ratio of mid to short species increased with time from treatment. With the exception of bulk density, aggregate stability, and calcium, most soil properties analysed in the study were not significantly different among geographic regions, herbicide treatments, or creosotebush condition (live vs. dead plants). Results indicated a trend of nitrogen and phosphorus shifting from the canopy zone towards interspace areas following creosotebush death.