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Landform: Mountains
Elevation: 4,500 to 6,300 feet
Slope range: 15 to 30 percent
Vegetation: Conifers, shrubs, and grasses
Mean annual precipitation: 40 to 60 inches
Mean annual air temperature: 39 to 44 degrees F
Mean annual soil temperature: 41 to 46 degrees F
Frost-free period: 50 to 80 days

Position on the landscape: Side slopes
Parent material: Slope alluvium from andesitic debris flow
Typical profile:
1 inch to 0—duff
0 to 7 inches—dark brown very gravelly sandy loam
7 to 46 inches—brown very gravelly sandy loam
46 inches—weathered andesite
Depth class: Deep
Drainage class: Well drained
Slowest permeability class: Moderately rapid
Available water capacity: Very high
Highest shrink-swell potential: Low
Surface runoff: Rapid
Depth to bedrock: 40 to 60 inches
Hazard of water erosion in bare areas: Low or moderate

Position on the landscape: Side slopes
Parent material: Debris flow over residuum from nonvesicular material over vesicular andesitic basalt
Typical profile:
0 to 10 inches—dark brown and brown gravelly sandy loam
10 to 27 inches—brown very cobbly sandy loam
27 inches—weathered andesite
Depth class: Moderately deep
Drainage class: Well drained
Slowest permeability class: Moderately rapid
Available water capacity: Very high
Highest shrink-swell potential: Low
Surface runoff: Rapid
Depth to bedrock: 20 to 40 inches
Hazard of water erosion in bare areas: Moderate

• Bundora and Goulder soils, which are more than 60 inches deep and have an argillic horizon; on foot slopes
• Soils that are similar to the Mounthat soil but are less than 20 inches deep; on side slopes and shoulders

Land use: Timber production

Main tree species: White fir, incense cedar, California red fir, sugar pine
Mean site index for stated species: White fir—71
Dunning site class: 1
CACTOS site index: 78
Common understory plants: Serviceberry, snowberry, gooseberry, princes pine, Sierra chinkapin, rose

Main tree species: White fir, sugar pine, California black oak, incense cedar, ponderosa pine
Mean site index for stated species: White fir—69
Dunning site class: 1
CACTOS site index: 84
Common understory plants: Greenleaf manzanita, gooseberry, serviceberry, brackenfern, princes pine

Major management factors: Obie—water erosion, plant competition; Mounthat—water erosion, depth to rock, plant competition

Management considerations:

• Maintaining a cover of vegetation, such as low-growing plants, limbs, and duff, on about 60 percent of the surface helps to control erosion during periods of intense rainfall and spring snowmelt.
• Roads and landings can be protected from erosion by constructing water bars.
• Erosion can be severe during intense thunderstorms in the summer and during warm storms in the winter when the material below the surface is frozen. Measures that control erosion are needed to prevent soil loss.
• Because of the limited soil depth, keeping soil displacement and disturbances to a minimum helps to maintain long-term productivity.
• Plant competition delays natural regeneration but does not prevent the eventual development of a fully stocked, normal stand of trees.
• Maintenance of evenly distributed organic material, such as limbs and needles, improves long-term productivity and the nutrient balance of the site. A balance between fire hazard reduction and long-term productivity should be considered.
• Trees suitable for planting include white fir, sugar pine, ponderosa pine, and California red fir.

Land capability classification: Obie—IVe-4, nonirrigated; Mounthat—IVs-7, nonirrigated
MLRA: 22
Prime farmland: Not considered prime farmland
Woodland ordination symbol: Obie—12F; Mounthat—11F