Description:
Chihuahuan Creosotebush Desert Scrub
The view west, at 4200 feet, from the east side of Dos Cabezas near Apache Pass, 12 August 2010. Creosote is the clear dominant, 1.2 meters tall, with 41-60% cover. Associates include mesquite (only 1.0 meter tall, 5-9% cover), and an occasional soaptree yucca and prickly pear.
Description
The Chihuahuan Creosotebush Desert Scrub ecosystem ranges from 4000 to 5000 feet, exclusively on slopes less than 10 degrees (18%), virtually all of which is on the southwest side of the Dragoons, the south end of the Swisshelm Mts near Leslie Canyon, and a few miles northeast of Apache Pass, near the Dos Cabezas Mountains. It is associated with fans that are downslope of limestone.
The creosote can be dominant, or co-dominate with whitethorn acacia and/or mariola (Parthenium incanum), as in the photo below.
The view northeast, at 4700 feet, near the powerline corridor on the west side of the Dragoons, 30 August 2010. Mariola, creosote, and whitethorn combine for 26-40% cover. Common associates include ocotillo, fairyduster (Calliandra eriophyllum) and Zinnia acerosa. Littleleaf sumac trees, 2 to 3 meters tall, are tucked into watercourses.
Other Vegetation Classifications
The Chihuahuan Creosotebush Desert Scrub ecosystem includes elements of several vegetation types mapped or described in other classification schemes. In each of the six schemes referred to below, the * symbol marks the vegetation type most similar to the Chihuahuan Creosotebush Desert Scrub ecosystem.
And what is meant by ‘most similar’? For the USFS Plant “Habitat Type” (Potential Association), the USFS “Potential Natural Vegetation Type” (PNVT), and the Brown, Lowe, and Pase “Biome”, the * symbol denotes the best fit based on the description of the Habitat Type, PNVT, or Biome. For the Landfire, ReGap, and USFS mid-scale classifications, which are presently mapped at a 30 meter resolution and were used in creating the map, the * symbol denotes the classification that was most commonly attributed within the Chihuahuan Creosotebush Desert Scrub, as mapped in this effort.
Landfire Existing Vegetation Type (EVT)
Chihuahuan Creosotebush Desert Scrub *
Sonoran Paloverde-Mixed Cacti Desert Scrub (Note: not present in study area)
Chihuahuan Mixed Salt Desert Scrub (Note: not present in study area)
Apacherian-Chihuahuan Mesquite Upland Scrub
Apacherian-Chihuahuan Semi-Desert Grassland and Steppe
USFS Mid-scale Dominance Type
Desert and Semi-desert Shrub Mix (ARPU5, FOSP2, OPUNT_PRVE, PRVE, SDMX, SEDX)
USFS Plant Habitat Type (Potential Association)
Not identified
USFS Potential Natural Vegetation Type (PNVT)
Possibly “Desert Communities – Lower”
Brown, Lowe, and Pase Biome
Sonoran Desertscrub *
Southwest Regional GAP Ecological System
Chihuahuan Creosotebush, Mixed Desert, and Thornscrub (similar to the Chihuahuan Creosotebush Desert Scrub)
Semi-Desert Grassland and Steppe*
Apacherian-Chihuahuan Mesquite Upland Scrub
