LOCATION HIERRO COEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Eutric Haplocryalfs
TYPICAL PEDON: Hierro loam, forested. (Colors are for dry soil unless otherwise stated.)
0i1--0 to 1 inches; slightly decomposed forest litter consisting primarily of needles, bark, and twigs.
0e2--1 to 2 inches; partially decomposed organic material like that of the horizon above.
A--2 to 6 inches; reddish gray (5YR 5/2) loam, dark reddish brown (5YR 3/2) moist; moderate very fine crumb structure; soft, very friable; many roots; slightly acid; clear wavy boundary. (0 to 5 inches thick)
E--6 to 12 inches; pinkish gray (5YR 6/2) loam, dark reddish gray (5YR 4/2) moist; weak medium subangular blocky structure that parts to moderate very fine granules; soft, very friable; many roots; neutral; clear wavy boundary. (5 to 12 inches thick)
Bt1--12 to 17 inches; reddish brown (5YR 5/3) sandy clay loam, reddish brown (5YR 4/3) moist; moderate medium subangular blocky structure that parts to moderate very fine granules; soft, very friable; common thin clay films on peds; many roots; few reddish sandstone flagstones; neutral; clear wavy boundary.
Bt2--17 to 23 inches; reddish brown (5YR 5/3) sandy clay loam, reddish brown (5YR 4/4) moist; moderate medium angular blocky structure that parts to moderate very fine granules; soft, very friable; common thin clay films on peds; many roots; 10 percent sandstone flagstones; slightly acid; clear wavy boundary. (Combined thickness of the Bt1 and Bt2 horizons is 6 to 35 inches)
BCt--23 to 31 inches; reddish brown (5YR 5/3) flaggy sandy clay loam, dark reddish brown (5YR 3/3) moist; weak fine subangular blocky structure; soft, very friable; few thin discontinuous clay films on vertical faces of peds; few roots; 30 percent sandstone flagstones; moderately acid; clear wavy boundary. (6 to 10 inches thick)
C--31 to 62 inches; reddish brown (5YR 5/4) very flaggy loam, dark reddish brown (5YR 3/4) moist; massive; soft, very friable; 40 percent sandstone flagstones; moderately acid.
TYPE LOCATION: Gunnison County, Colorado; on the west side of Cement Creek just above the spring in the W1/2, Sec. 3, T. 13 S., R. 84 W.
RANGE IN CHARACTERISTICS:
Soil moisture regime: udic bordering on ustic.
Thickness of the solum ranges from 21 to 65 inches.
Depth to carbonates: noncalcareous throughout, and there is little or no increase in pH with depth.
A horizons are thin and are absent in some pedons.
Base saturation: 60 to 100 percent base saturation.
Rock fragment: 5 to 35 percent in the B and C horizons above a depth of 40 inches; and are dominantly in the shape and size of flagstones, but include gravel, cobbles and stones.
The A horizon, when present:
Hue: 7.5YR through 5YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 1 or 2
Reaction: moderately acid to neutral
E horizon:
Hue: 7.5YR through 2.5YR
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 2 or 3
Reaction: moderately acid to neutral
The Bt horizons:
Hue: 5YR or 2.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4
Reaction: moderately acid to neutral
Texture of the fine earth fraction: sandy clay loam, clay loam or loam
Clay content: 18 to 35 percent
Silt content: 10 to 40 percent
Sand content: 30 to 70 percent sand, with more than 35 percent being fine or coarser sand.
The C horizon, when present:
Hue: 5YR OR 2.5YR
Reaction: moderately acid to neutral
COMPETING SERIES: These are the
Haviland(CO),
Jaegie(MT),
Sapphire(MT)
Tongue River(WY), and
Weminuche series.
Haviland soils usually have a moisture control section that is usually moist when the soil temperature is
greater than 41 degrees F.
Jaegie soils have an E/Bt horizon and lacks hues of 5YR or redder in the Bt horizon.
Sapphire soils have a lithic contact at 20 to 40 inches.
Tongue River soils have a paralithic contact at 20 to 40 inches.
Weminuche soils have E/B horizons.
GEOGRAPHIC SETTING:
Parent material: alluvium and colluvium from red sandstone and sedimentary rocks
Landform: alluvial fans, mountain slopes, and valley side slopes
Elevation: 8,000 to 11,000 feet
Slopes: 2 to 50 percent.
Mean annual precipitation is 26 to 30 inches, with peak periods of precipitation during the spring and summer.
Mean annual temperature ranges from 32 to 42 degrees F.
The frost-free season is about 40 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ashcroft and Sawcreek soils and the competing Limber soils. Ashcroft soils have less than 18 percent clay in the control section. Sawcreek soils have mollic epipedons.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderate permeability.
USE AND VEGETATION: These soils are used for rangeland, for forestry, wildlife habitat and recreation. Native vegetation is mainly Engelmann spruce, subalpine fir, scattered grasses, and vaccinium.
DISTRIBUTION AND EXTENT: High mountainous areas of central Colorado; LRR E, MLRA 48A. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Gunnison County, Colorado, 1975.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: the zone from 2 to 6 inches (A horizon).
Albic horizon: the zone from 6 to 12 inches (E horizon).
Argillic horizon: the zone from 12 to 31 inches (Bt1, Bt2, and BCt horizons).
4/2001 the precipitation range was narrowed to exclude less than 26 inches to limit this series to the typic-udic moisture regime.
Taxonomic version: Eighth Edition, 1998