Major Land Resource Area 044B
Central Rocky Mountain Valleys
Accessed: 10/07/2024
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Explore the ecological site description
Next, learn more about the selected ecological site and its characteristic dynamics by browsing the ecological site description and exploring alternative state and transition model formats.
Ecological site list
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT sand or loamy sand texture
- Slope < 15%
- Soil texture NOT sandy loam to fine sandy loam
- Soil Clay content >32% in surface mineral 4" (ribbon ≥ 2")
- Clay content >32%-45% within surface mineral 4" -- Clayey (Cy)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil Saline or Saline-Sodic within surface 20" or soils with natric or relic natric horizons
- Columnar structure present, abrupt root or water restrictive clay layer present within 8" of soil surface
- Soil has 4" to 8" of surface over clay layer (evidence of columnar structure) -- Claypan (Cp)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil Sandy-Skeletal
- Soil sandy-skeletal within 10" of soil surface -- Gravelly (Gr)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil strongly or violently effervescent in surface mineral 4" -- Limy (Ly)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil loamy-skeletal or clayey-skeletal
- Soil strongly or violently effervescent within top 4" -- Limy Droughty (LyDr)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT sand or loamy sand texture
- Slope < 15%
- Soil texture NOT sandy loam to fine sandy loam
- Soil Clay content ≤32% in surface mineral 4"
- Argillic horizon, if present in surface 20", has ≤ 32% clay (ribbon <2") -- Loamy (Lo)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil loamy-skeletal or clayey-skeletal
- Soil NOT strongly or violently effervescent within surface mineral 4"
- Slope < 15% -- Droughty (Dr)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil loamy-skeletal or clayey-skeletal
- Soil NOT strongly or violently effervescent within surface mineral 4"
- Slope ≥ 15% -- Droughty Steep (DrStp)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT sand or loamy sand texture
- Slope ≥ 15%
- Mollic epipedon present
- Clay content is ≤ 32% in surface mineral 4" (ribbon < 2") -- Loamy Steep (LoStp)
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Key Characteristics
- Site receives additional effective moisture.
- Soil Not Saline
- Seasonal high water table ≥ 40" from ground surface; site regularly receives more than normal soil moisture from run-in and stream overflow -- Overflow (Ov)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil Saline or Saline-Sodic within surface 20" or soils with natric or relic natric horizons
- No columnar structure; site dominated by salt tolerant plants -- Saline Upland (SU)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT sand or loamy sand texture
- Slope < 15%
- Soil Coarse sandy loam to fine sandy loam texture within surface mineral 4" -- Sandy (Sy)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT skeletal (<35% rock fragments in 10-20" layer)
- Soil clay content >32% in surface mineral 4" (ribbon >2")
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil is strongly or violently effervescent (calcareous) in surface mineral 4"; lime concentrations often increase with depth
- Soil NOT skeletal (<35% rock fragment in 10-20" layer) -- Shallow Limy (SwLy)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil Sandy-Skeletal
- Soil sandy-skeletal within 10-20" of soil surface
- Soil NOT strongly or violently effervescent within surface mineral 4" -- Shallow to Gravel (SwGr)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil is strongly or violently effervescent (calcareous) in surface mineral 4"; lime concentrations often increase with depth
- Soil skeletal (≥35% rock fragment in the 10-20" layer) -- Shallow Limy Droughty (SwLyDr)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT skeletal (<35% rock fragments in 10-20" layer)
- Soil clay content ≤ 32% in surface mineral 4" (soil ribbon ≤ 2") -- Shallow Loamy (SwLo)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil Sandy-Skeletal
- Soil sandy-skeletal within 10-20" of soil surface
- Soil strongly or violently effervescent within surface mineral 4" -- Shallow to Gravel, Limy (SwGrLy)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodi
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil Skeletal (≥35% rock fragments in 10-20" layer) -- Shallow Droughty (SwDr)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil Saline or Saline-Sodic within surface 20" or soils with natric or relic natric horizons
- Columnar structure present, abrupt root or water restrictive clay layer present within 8" of soil surface
- Less than 4" of soil surface over clay layer (evidence of columnar structure) -- Thin Claypan (TCp)
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil strongly or violently effervescent in surface mineral 4"
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil loamy-skeletal or clayey-skeletal
- Soil strongly or violently effervescent within top 4"
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil NOT strongly or violently effervescent in surface mineral 4" -- Sands (Sa)
- Soil NOT sand or loamy sand texture
- Slope < 15%
- Soil texture NOT sandy loam to fine sandy loam
- Soil Clay content ≤32% in surface mineral 4" - Loamy Argillic (LoA)
- Argillic horizon, if present in surface 20", has ≤ 32% clay (ribbon <2")
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil loamy-skeletal or clayey-skeletal
- Soil NOT strongly or violently effervescent within surface mineral 4"
- Slope < 15%
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil skeletal (≥35% rock fragment in the 10-20" layer)
- Soil loamy-skeletal or clayey-skeletal
- Soil NOT strongly or violently effervescent within surface mineral 4"
- Slope ≥ 15%
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soils moderately deep, deep, or very deep (≥ 20" deep to bedrock, lithic, or paralithic root restrictive layer
- Soil NOT skeletal (<35% rock fragment in 10-20" layer)
- Soil NOT strongly or violently effervescent in surface mineral 4" -- Sands (Sa)
- Soil NOT sand or loamy sand texture
- Slope ≥ 15%
- Mollic epipedon present
- Clay content is ≤ 32% in surface mineral 4" (ribbon < 2")
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Key Characteristics
- Site receives additional effective moisture.
- Soil Not Saline
- Seasonal high water table ≥ 40" from ground surface; site regularly receives more than normal soil moisture from run-in and stream overflow
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT skeletal (<35% rock fragments in 10-20" layer)
- Soil clay content >32% in surface mineral 4" (ribbon >2")
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil NOT skeletal (<35% rock fragments in 10-20" layer)
- Soil clay content ≤ 32% in surface mineral 4" (soil ribbon ≤ 2")
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Key Characteristics
- Site does not receive additional effective moisture
- Soil NOT Saline or Saline-Sodic
- Soil Shallow (10"-20" deep to bedrock, lithic, or paralithic root restrictive layer)
- Soil NOT strongly or violently effervescent in surface mineral 4"
- Soil Skeletal (≥35% rock fragments in 10-20" layer)
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Key Characteristics
- Not included in any other Key, Is in higher precipitation zones and is less than 35% clay and greater than 18% Clay, No argillic horizon, and less than 15% slope.
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Key Characteristics
- Site receives additional effective moisture.
- Soil Not Saline
- Seasonal high water table < 40" from ground surface
- Soil Not Organic
- Site located in Floodplain
- Seasonal high water table < 24"
- Seasonal high water table 12" to 24" -- Riparian Meadow (RM)
- Site receives additional effective moisture.
- Soil Not Saline
- Seasonal high water table < 40" from ground surface
- Soil Not Organic
- Site located in Floodplain
- Seasonal high water table < 24"
- Seasonal high water table 12" to 24"
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Key Characteristics
- Site receives additional effective moisture.
- Soil Not Saline
- Seasonal high water table < 40" from ground surface
- Soil Not Organic
- Site located in Floodplain
- Seasonal high water table 24" to 40" -- Riparian Subirrigated (RSb)
- Site receives additional effective moisture.
- Soil Not Saline
- Seasonal high water table < 40" from ground surface
- Soil Not Organic
- Site located in Floodplain
- Seasonal high water table 24" to 40"
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Key Characteristics
- Forestland Groups
- All other Forest Types
- Cooler temperatures with higher elevations
- Coldest and highest elevation, just below timberline or on north and east aspects -Cold Woodland
- Additional moisture available, meadows or snow-catch areas - Cold-Moist Woodland
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Key Characteristics
- Forestland Groups
- All other Forest Types
- Cooler temperatures with higher elevations
- Cool temperatures, mid-elevation range, and variable aspect.
- Additional moisture available, meadows or snow-catch areas - Cool-Moist Woodland
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Key Characteristics
- Forestland Groups
- Deciduous dominated community, dominantly Aspen - Aspen Woodland
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Key Characteristics
- Forestland Groups
- All other Forest Types
- Cooler temperatures with higher elevations
- Coldest and highest elevation, just below timberline or on north and east aspects -Cold Woodland
- No additional moisture - Cold Woodland
- Soil is not strongly or violently effervescent
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Key Characteristics
- Forestland Groups
- All other Forest Types
- Cooler temperatures with higher elevations
- Cool temperatures, mid-elevation range, and variable aspect.
- No additional moisture - Cool Woodland
- Soils are not shallow
- Soil is not strongly or violently effervescent
- Soils do not have a high amount of rock fragments on the surface.
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Key Characteristics
- Forestland Groups
- All other Forest Types
- Warmer temperatures, generally related to lower elevations, south and west aspects - Warm Woodland
- Soils are not shallow
- Soils are not strong to violently effervescent
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Key Characteristics
- Forestland Groups
- All other Forest Types
- Cooler temperatures with higher elevations
- Cool temperatures, mid-elevation range, and variable aspect.
- No additional moisture - Cool Woodland
- Soils are not shallow
- Soil is strongly or violently effervescent (CaCO3 > 14%) in surface mineral 18cm – Limy
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Key Characteristics
- Rangeland Groups
- Significant additional water influences community.
- Soils are associated with a stream or live water and are in a riparian or lowland situation.
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils influenced by chemistry within the upper soil profile.
- Soil is strongly or violently effervescent (CaCO3 > 14%) in surface mineral 18cm – Limy
- Dominated by grasses and grasslike species - Grassland
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils influenced by chemistry within the upper soil profile.
- Soil is strongly or violently effervescent (CaCO3 > 14%) in surface mineral 18cm – Limy
- Dominated by shrubs
- Sagebrush is the dominant shrub - Sagebrush Shrubland
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils influenced by chemistry within the upper soil profile.
- Soil saline or sodic (EC > 7 or SAR > 12 within surface 18cm)
- Dominated by grasses and grasslike species - Grassland
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils influenced by chemistry within the upper soil profile.
- Soil saline or sodic (EC > 7 or SAR > 12 within surface 18cm)
- Dominated by shrubs
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils not influence by chemistry
- Soils are shallow (less than 20 inches to a restrictive layer, root limiting layer, or bedrock)
- Dominated by grasses and grasslike species - Grassland
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils not influence by chemistry
- Soils are shallow (less than 20 inches to a restrictive layer, root limiting layer, or bedrock)
- Dominated by shrubs
- Sagebrush is the dominant shrub - Sagebrush Shrubland
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils not influence by chemistry
- Soils are shallow (less than 20 inches to a restrictive layer, root limiting layer, or bedrock)
- Dominated by shrubs
- All other shrubs - Shrubland
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Key Characteristics
- Rangeland Groups
- Significant additional water influences community.
- Not in a riparian situation, but has a water table present.
- Soil saline or sodic (EC > 7 or SAR > 12 within surface 18cm)
- Community is Grass and grasslike dominated, water table within rooting depth of herbaceous species, limiting woody vegetation (less than 100 cm from the ground surface for part of the growing season).
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Key Characteristics
- Rangeland Groups
- Significant additional water influences community.
- Not in a riparian situation, but has a water table present.
- Soil saline or sodic (EC > 7 or SAR > 12 within surface 18cm)
- Community is shrub dominated, water table within rooting depth of herbaceous species, limiting woody vegetation (greater than 100 cm from the ground surface for part of the growing season).
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Key Characteristics
- Rangeland Groups
- Significant additional water influences community.
- Not in a riparian situation, but has a water table present.
- Soils are not saline or sodic
- Community is Grass and grasslike dominated, water table within rooting depth of herbaceous species, limiting woody vegetation (less than 100 cm from the ground surface for part of the growing season).
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Key Characteristics
- Rangeland Groups
- Significant additional water influences community.
- Not in a riparian situation, but has a water table present.
- Soils are not saline or sodic
- Community is shrub dominated, water table within rooting depth of herbaceous species, limiting woody vegetation (greater than 100 cm from the ground surface for part of the growing season).
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils not influence by chemistry
- Soils are not shallow
- Soils do not contain a high amount of rock fragments on the soil surface.
- Dominated by grasses and grasslike species - Grassland
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils not influence by chemistry
- Soils are not shallow
- Soils do not contain a high amount of rock fragments on the soil surface.
- Dominated by shrubs
- Sagebrush is the dominant shrub - Sagebrush Shrubland
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Key Characteristics
- Rangeland Groups
- Not water controlled - upland
- Soils not influence by chemistry
- Soils are not shallow
- Soils do not contain a high amount of rock fragments on the soil surface.
- Dominated by shrubs
- All other shrubs - Shrubland
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The Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.