2011-04-08_REVISION - M1983011 ‎(6)‎

• Permit No: M1983011
• IBM Index Class Name: REVISION
• Doc Date: 4/8/2011
• Doc Name: Conversion application ‎(CN-01)‎ to a 112
• From: Mt. Elbert Mining Co., LLC
• To: DRMS
• Type & Sequence: CN1
• Email Name: DMC
• Media Type: D
• Archive: No

Soil and ecological land unit survey
Improved unsurfaced roads:
Taglake: severe- slope.
Offroad vehicle roads and trails:
Taglake: severe- slope, cobbles and stones.
Foot trails and paths:
Taglake: moderate- slope.
Revegetation limitations:
Taglake: severe- slope, low available water
capacity and erosion hazard.
Revegetation considerations: Mulch will
conserve soil moisture and protect seedling
establishment. Surface netting will reduce the
erosion hazard.
Timber management considerations: Plant
trees that are drought tolerant or revegetate with
grasses and forbs. Trees to plant include
lodgepole pine.
Wildlife management considerations: This map
unit provides shelter and limited food during
summer through fall months. Thinning or
creating small openings in the overstory canopy
cover can stimulate understory productivity.
Other management considerations:
Management activities are limited by steep slopes
and erosion hazard.
Acid precipitation buffering capacity. moderate.
Map Unit: 610G-Leighcan family, 5 to 40 percent
slopes.
Ecological Land Unit: 610G-subalpine fir and
Engelmann spruce on subalpine ground and
lateral moraines and valley fill.
MAP UNIT SETTINGS
Location: glaciated areas where igneous and
metamorphic rocks predominate.
Landform: ground and lateral moraines and valley
fill.
Parent material. glacial till and fluvial valley fill.
Geologic symbol. Qd and Qa.
Elevation range: 10,000 to 11,600 feet.
Aspect. all.
Climatic zone: subalpine.
Mean annual precipitation: 20 to 40 inches.
Mean annual air temperature: 340F, to 400F.
Average annual snowfall: 300 to 400 inches.
COMPOSITION
85 percent Leighcan and similar soils.
Contrasting inclusions
8 percent Cryaquolls along stream drainages and
seeps.
5 percent rubbly glacial debris.
2 percent soils that lack development.
TYPICAL PROFILES:
Leighcan
Surface covering layer:
2.5 to 0 inches - conifer litter and duff.
Surface layer(s):
0 to 1 inches - very dark grayish brown, very
stony loam.
Subsurface layer(s):
1 to 7 inches - brown, very stony sandy loam.
7 to 12 inches - brown, extremely cobbly sandy
loam.
Subsoil layer(s):
12 to 32 inches - dark yellowish brown,
extremely cobbly sandy loam.
32 to 50 inches - yellowish brown, extremely
stony sandy loam.
Substratum layer(s):
50 to 65 inches - light olive brown, extremely
stony loamy sand.
SOIL PROPERTIES AND QUALITIES
Leighcan
Effective rooting depth: greater than 60 inches.
Drainage class: somewhat excessively.
Depth to seasonal high water table: greater
than 6 feet.
Available water capacity. very low to low.
Permeability., moderately rapid.
Runoff. medium.
VEGETATION
Potential natural communities:
Leighcan: subalpine fir-Engelmann
spruce/Rocky Mountain whortleberry (Abla-
PienlNamy) above 11,000 feet and lodgepole
pine/Rocky Mountain whortleberry (PicoNamy)
below 10,000 feet.
Sera/ stages: dominated by plants of the
respective potential natural communities.
Present vegetation: dominated by plants of the
respective potential natural communities.
USE AND MANAGEMENT CONSIDERATIONS
Major uses: homesites, timber harvest, firewood
harvest, limited livestock grazing, wildlife habitat
and, watershed.
Mass movement potential:
Landslides: low.
Debris flows: low.
Snow avalanche: low.
Sediment delivery efficiency. low.
Road and trail limitations:
Cut and fill slope stability
Leighcan: slight.
Improved unsurfaced roads:
Leighcan: slight.
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