Ecological site group DX035X01CESG04
Mesas and Benches - Saline Hills and Badlands - gypsic
Last updated: 10/05/2022
Accessed: 05/02/2024
Ecological site group description
Key Characteristics
- Mesa and Benches
- Saline Hills and Badlands
- Soil parent material is dominantly gypsiferous
Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.
Physiography
The sites in this group occur on hills, pediments, alluvial fans, valleys, ridges, and structural benches at elevations between 4300-6000 feet. Slopes range from 2-50 percent.
Climate
This site is hot in the summer and cool in the winter. Average annual precipitation is 6 to 9 inches, with about half of the precipitation occuring as convection thunderstorms from July through October. June is typically the driest month during the growing season. Precipitation is extremely variable from month to month and from year to year. Large fluctuations in daily temperatures are also common.
Soil features
Soils are very shallow to deep and are gypsum affected. Soil textures range from very fine sandy loams to loamy fine sands with moderately rapid permeability. These soils formed in residuum or slope aluvium derived from sandstone material high in gypsum. Rock fragments range from 0 to 30 percent on the soil surface or throughout the profile. The soil moisture regime is typic aridic and the soil temperature regime is mesic. Water-holding capacity ranges from 2 to 3 inches of water in the upper 40 inches of soil or to gypsum bedrock. Water and wind erosion hazard is severe. Runoff is high.
Vegetation dynamics
This group developed under Colorado Plateau ecological conditions and the natural influences of herbivory and climate. This site’s plant species composition is generally dominated by Torrey's jointfir, shadscale, crispleaf buckwheat, James' galleta, and Indian ricegrass. Crispleaf buckwheat can occasionally dominate on steep north exposures. James galleta, Indian ricegrass and other perennial grass production is somewhat dependant on weather patterns (summer or winter precipitation).
There is no evidence that sites in this group historically burned on a regular basis due to very large and persistent gaps between plants. However, modern disturbances such as recreation and livestock grazing, may result in an opportunity for invasive annuals to enter the system.
This ecological site has been grazed by domestic livestock since they were first introduced into the area around 1860. It is highly resistant to grazing due to the low palatability of Torrey's jointfir and lack of forage plants. The introduction of domestic livestock and the use of fencing and reliable water sources have therefore only minimally influenced the historic disturbance regime associated with this group
Major Land Resource Area
MLRA 035X
Colorado Plateau
Subclasses
Correlated Map Unit Components
22338511, 22592321, 22592458, 22592362, 22592365, 22592366, 22592369, 22592493, 22592739
Stage
Provisional
Contributors
Vic Parslow
Keith Crossland
Jim Harrigan
Harry Hosler
Curtis Talbot
Click on box and path labels to scroll to the respective text.
Ecosystem states
T1A | - | D = Drought E = Establishment of non-native invasive species ILG = Improper livestock grazing SD = Surface disturbances |
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State 1 submodel, plant communities
1.1a | - | D = Drought ILG = Improper livestock grazing SD = Surface disturbances |
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1.2a | - | PLG = Proper livestock grazing T = Time without disturbances W = Wet weather periods |
State 2 submodel, plant communities
2.1a | - | D = Drought ILG = Improper livestock grazing SD = Surface disturbances |
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2.2a | - | PLG = Proper livestock grazing T = Time without disturbances W = Wet weather periods |