Ecological site group DX035X01IESG11
Little Colorado River Basin-Loamy Soils moderately deep or deeper (slopes<15% and <35% rock fragments)
Last updated: 10/25/2022
Accessed: 05/02/2024
Ecological site group description
Key Characteristics
- Little Colorado River Basin
- Loamy
- Does not receive extra run-in moisture
- Moderately deep or deeper
- Slopes are less than 15% and upper part of soil has less than 35% rock fragments
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
This ecological site occurs in an upland position as gently rolling plains, fans and terraces. Slopes generally range from 0% to 15% with occasional steeper slopes up to 30%.
This site neither benefits significantly from run-in nor experiences excessive loss of moisture from runoff.
Climate
50-60% of moisture falls as rain from July through September and is the most effective moisture for plant growth. The remaining moisture comes as snow during the winter.
Mean temperature for the hottest month (July) is 72 F; for the coldest month (January) is 32 F. Extreme temperatures of 105 F and -28F have been recorded. Long periods with little or no effective moisture are relatively common.
Cool season plants begin growth in early spring and mature by early summer. Warm season plants take advantage of summer rains and actively grow from July through September.
Soil features
Soils grouped in this site are moderately deep or deeper to any plant root restricting layers. The surface horizons have textures of very fine sandy loam to sandy clay loam with various amounts of gravel on the surface. The surface layers are about 2 to 8 inches thick. The subsurface horizons have textures ranging from clay to loam with coarse fragments ranging from 0 to 40% by volume. The substratum, which occurs at depths of 15 to 36 or more inches, ranges from clay loam to very gravelly sand and in some soils has a strong accumulation of lime. The soil reaction is neutral to moderately alkaline (pH 6.6 to 8.4). Soluble salt accumulations are low.
Vegetation dynamics
The plant communities found on an ecological site are naturally variable. Composition and production will vary with yearly conditions, location, aspect, and the natural variability of the soils. The reference community represents the natural potential plant communities found on relict or relatively undisturbed sites. Other plant communities described here represent plant communities that are known to occur when the site is disturbed by factors such as grazing, fire, or drought.
Reference State
The reference state includes the reference community. The reference community is a perennial native grassland with warm season and cool season grasses and half-shrubs. Natural climatic variation can result in changes in the amount of and ratio of both individual plants and warm season versus cool season plants, particularly grasses.
The reference community consists primarily of warm season mid-grasses and short grasses with a mix of cool season grasses and half-shrubs. Dominant grasses include black grama, blue grama, squirreltail, indian ricegrass, galleta and sideoats grama. Dominant shrubs include winterfat and fourwing saltbush. Natural climatic variation result in changes in the amount of and ratio of both individual plants and warm season versus cool season plants, particularly grasses.
Major Land Resource Area
MLRA 035X
Colorado Plateau
Subclasses
Correlated Map Unit Components
22341066, 22341068, 22341071, 22341131, 22341133, 22341137, 22341139, 22341156, 22341600, 22341601, 22341644, 22341598, 22353858, 22353860, 22353956, 22354016, 22354017, 22354018, 22353347, 22353349, 22353365, 22353372, 22353373, 22353374, 22353375, 22353376, 22353368, 22353371, 22353382, 22353388, 22396791
Stage
Provisional
Contributors
Curtis Talbot
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