LOCATION MUMMY COEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, micaceous Typic Humicryepts
TYPICAL PEDON: Mummy extremely cobbly sandy loam , on a south facing, convex, 27 percent slope in tundra at an elevation of 12,335 feet. (Colors are for dry soil unless otherwise noted.) When described on August 5, 1996 the soil was moist from 0 to 60 inches. The surface is covered by 5 percent boulders, 15 percent stones, and 30 percent cobbles.
A--0 to 5 inches; dark grayish brown (10YR 4/2) extremely cobbly sandy loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very friable, slightly sticky and nonplastic; many very fine and fine roots throughout and common medium; 15 percent gravel, 30 percent cobbles and 20 percent stones; very strongly acid (pH 4.8); abrupt wavy boundary. (4 to 10 inches thick)
Bw1--5 to 24 inches; brown (10YR 5/3) extremely cobbly sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine and fine roots throughout and few medium; 15 percent gravel, 30 percent cobbles and 20 percent stones; strongly acid (pH 5.4); clear smooth boundary. (6 to 20 inches thick)
Bw2--24 to 72 inches; yellowish brown (10YR 5/4) extremely cobbly sandy loam, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots throughout and few medium; 20 percent gravel, 30 percent cobbles and 10 percent stones; strongly acid (pH 5.2). (30 to 62 inches thick)
TYPE LOCATION: Larimer County, Colorado; about 10 miles west of Estes Park, about 3.8 miles southeast of Fall River Pass; Trail Ridge USGS quad; lat. 40 degrees 24 minutes 24 seconds N. and long. 105 degrees 42 minutes 04 seconds W., NAD 1927
RANGE IN CHARACTERISTICS:
Soil moisture regime: Udic moisture regime
Mean annual soil temperature: 32 to 36 degrees F
Mean summer soil temperature: 43 to 47 degrees F
Thickness of the umbric epipedon: 10 to 30 inches
Particle-size control section (weighted average):
Clay content: 8 to 18 percent
Sand content: 45 to 75 percent
Rock fragments: 45 to 65 percent,
Mica content: 40 to 70 percent (by grain count)
A horizon:
Hue: 7.5YR or 10YR
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 2 or 3
Texture: gravelly sandy loam, extremely cobbly sandy loam
Clay content: 10 to 18 percent
Rock fragments: 15 to 75 percent, dominantly gravel and cobbles
Base saturation: 10 to 40 percent
Reaction: very strongly acid or strongly acid
Bw1 horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6 dry, 2 to 4 moist
Chroma: 2 to 3
Texture: extremely cobbly sandy loam, very gravelly sandy loam, very gravelly loam
Clay content: 10 to 20 percent
Rock fragments: 30 to 75 percent, dominantly gravel and cobbles
Base saturation: 10 to 50 percent
Reaction: very strongly acid or strongly acid
Bw2 horizon:
Hue: 7.5YR to 10YR
Value: 5 to 7 dry, 3 to 5 moist
Chroma: 3 to 6
Texture: very gravelly sandy loam, extremely cobbly coarse sandy loam, extremely cobbly sandy loam, very gravelly loam, very gravelly coarse sandy loam, very cobbly sandy loam. Some pedons have a texture (fine earth fraction) of loamy coarse sand below a depth of 40 inches.
Clay content: 8 to 18 percent
Rock fragments: 35 to 75 percent, dominantly gravel and cobbles
Base saturation: 40 to 60 percent
Reaction: very strongly acid to moderately acid
COMPETING SERIES: This is the
Archrock series. Other series that may be competitors when reclassified are the
Afley,
Causewa,
Drakespeak,
Hossick,
McCall,
Moran, and
Sibelia series.
Archrock soils are 20 to 40 inches deep to a paralithic contact.
Afley and Causewa soils are 20 to 40 inches deep to a lithic contact.
Drakespeak soils have a xeric moisture regime.
McCall soils have mean annual soil temperature higher than 36 degrees and are assumed to have a xeric moisture regime.
Moran soils have less than 25 percent mica.
GEOGRAPHIC SETTING:
Parent material: colluvium and till derived from granitic rocks, gneiss, and schist
Landform: mountain
Slopes: 10 to 60 percent
Elevation: 10,400 to 12,200 feet
Mean annual temperature: 34 to 38 degrees F
Mean annual precipitation: 30 to 40 inches
Precipitation pattern: Wettest months: March, April, and May
Driest months: September and October
Frost-free period: 10 to 30 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Trailridge and
Archrock series. The Trailridge soils are shallow and are on ridges, shoulders, and summits of mountain tops.
The Archrock soils are moderately deep and are on ridges, shoulders, and summits of mountain slopes.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained, high runoffvery high runoff, moderately rapid permeability.
USE AND VEGETATION: Recreation and wildlife. The present vegetation is alpine bluegrass, kobresia, alpine timothy, rock sedge, golden avens, American bistort, senecio, and alpine clover.
DISTRIBUTION AND EXTENT: Mountains of the northcentral Rocky Mountains, Colorado; LRR E, MLRA 48A; this series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Larimer County, Colorado, Rocky Mountain National Park Soil Survey Area, 1999. The name is taken from the mountain range.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Umbric epipedon: The zone from 0 to 24 inches. (A1 and A2 horizons)
Cambic horizon: The zone from 24 to 60 inches. (Bw horizon)
Particle-size control section: The zone from 10 to 40 inches. (part of the A2 and the Bw horizons)
Remarks: Previously recognized as the Moran series but was changed due the high mica content and thick solum.
Keys to Soil Taxonomy: Series classified according to Eighth Edition, 1998.
The mineralogy class was changed from paramicaceous to micaceous in 07/2010 by the National Soil Survey Center on request of the responsible MLRA regional office. The change was necessary based on the eleventh edition of the Keys to Soil Taxonomy, 2010.