LOCATION STORM COEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Haplocryepts
TYPICAL PEDON: Storm extremely flaggy loam - woodland. (Colors are for dry soil unless otherwise noted. Reaction is from field-measured pH, not from lab.)
Oe--0 to 2 inches; partially decomposed organic and fibric material. (0 to 4 inches thick)
A--2 to 6 inches; dark brown (10YR 3/3) extremely flaggy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure parting to weak fine granular; slightly hard, very friable, moderately sticky and moderately plastic; many very fine to coarse roots throughout; many very fine interstitial pores; 20 percent gravel, 30 percent cobble and 40 percent flagstones; moderately acid (pH 5.9); clear smooth boundary. (0 to 5 inches thick)
E--6 to 13 inches; pale brown (10YR 6/3) extremely flaggy loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure parting to weak fine subangular blocky; slightly hard, very friable, moderately sticky and moderately plastic; many very fine and fine, and few medium and coarse roots; many very fine discontinuous tubular pores; 20 percent gravel, 25 percent cobble and 50 percent flagstones; moderately acid (pH 5.7); gradual wavy boundary. (3 to 13 inches thick)
Bw1--13 to 19 inches; pale brown (10YR 6/3) extremely flaggy clay loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine and fine, and few medium and coarse roots; many very fine discontinuous tubular pores; 25 percent gravel, 15 percent cobble, 35 percent flagstones; moderately acid (pH 5.6); clear smooth boundary.
Bw2--19 to 31 inches; light yellowish brown (10YR 6/4) very gravelly clay loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; hard, friable, slightly sticky and moderately plastic; few fine and common medium roots; common very fine discontinuous tubular pores; 35 percent gravel, 10 percent cobble and 5 percent flagstones; moderately acid (pH 5.6); clear smooth boundary.
Bw3--31 to 40 inches; very pale brown (10YR 7/4) extremely cobbly clay loam, yellowish brown (10YR 5/6) moist; weak fine subangular blocky structure; very hard, friable, slightly sticky and moderately plastic; few fine and common medium roots; common very fine discontinuous tubular pores; 35 percent gravel, 20 percent cobble and 15 percent flagstones; moderately acid (pH 5.6); clear wavy boundary. (combined thickness of the Bw horizons is 10 to 50 inches)
BC--40 to 48 inches; brownish yellow (10YR 6/6) very gravelly loam, yellowish brown (10YR 5/6) moist; massive; very hard, firm, moderately sticky and moderately plastic; few fine roots; few very fine discontinuous tubular pores; 30 percent gravel, 15 percent cobble and 5 percent flagstones; moderately acid (pH 5.6); clear wavy boundary. (0 to 12 inches thick)
C1--48 to 56 inches; very pale brown (10YR 7/4) extremely gravelly loam, brownish yellow (10YR 6/6) moist; few fine distinct light gray (10YR 7/1) mottles; massive; very hard, extremely firm, moderately sticky and moderately plastic; 50 percent gravel, 20 percent cobble and 5 percent flagstones; moderately acid (pH 5.6); gradual wavy boundary. (0 to 12 inches thick)
C2--56 to 62 inches; light yellowish brown (10YR 6/4) extremely gravelly clay loam, brown (10YR 4/3) moist; few fine distinct white (10YR 8/1) mottles; massive; hard, friable, moderately sticky and moderately plastic; 50 percent gravel, 10 percent cobble and 5 percent flagstones; moderately acid (pH 5.6).
TYPE LOCATION: Dolores County, Colorado; approximately 20 miles northeast of the community of Dolores, Colorado; 2,200 feet west and 600 feet north of the southeast corner of Sec. 8, T. 39 N., R. 12 W. (Area not sectionalized and sections projected on a topographic map.) Latitude 37 degrees 39 minutes 01 seconds N., longitude 108 degrees 12 minutes 02 seconds W. NAD 27.
RANGE IN CHARACTERISTICS:
(Depths given are measured from the mineral soil surface)
Soil moisture regime: udic; dry in some part of the moisture control section for less than 45 cumulative days (typic udic subclass).
Mean annual soil temperature: 36 to 42 degrees F.
Depth to the base of the cambic horizon: 20 to 60 inches
Base saturation: 60 to 90 percent throughout the upper 30 inches
Particle-size control section:
Clay content: 20 to 35 percent
Rock fragment content: 35 to 80 percent
A horizon:
Hue: 7.5YR or 10YR
Value: 3 through 5 dry, 2 or 3 moist
Chroma: 2 through 4, dry or moist
Reaction: strongly acid to slightly acid
E horizon:
Hue: 7.5YR or 10YR
Value: 5 through 7 dry, 2 through 4 moist
Chroma: 2 through 6, dry or moist
Texture (fine earth fraction): loam or sandy loam
Reaction: strongly acid to slightly acid
Bw horizon:
Hue: 7.5YR or 10YR
Value: 5 through 7, 2 through 5 moist
Chroma: 2 through 6, dry or moist
Texture (fine earth fraction): loam, clay loam, or sandy clay loam
Oxalate extractable Al+1/2Fe: .20 to .70 percent
Reaction: strongly acid to slightly acid
C horizon (not present in all pedons):
Hue: 7.5YR or 10YR
Value: 5 through 7, 4 through 6 moist
Chroma: 3 through 8, dry or moist
Texture (fine earth fraction): loam, clay loam, or clay
Reaction: strongly acid to slightly acid
Some pedons do not have mottled colors.
COMPETING SERIES: These are the Cuberant, Enentah, Firada, Garlet, Gromes, Targhee, and Telay. In addition, the following series may be competitors when their classification is updated: Blackleed, Poso, and Rosespringseries.
Blackleed,
Garlet, and soils: have less than 20 percent clay in the control section.
Cuberant soils: have a lithic contact at 20 to 40 inches.
Enentah soils: have less than 18 percent clay in the particle-size control section.
Firada, and
Targhee soils: have a lithic contact at a depth of less than 40 inches.
Gromes soils: do not have eluvial horizons and have metamorphic or igneous rock fragments.
Poso, Rosespring soils: have horizons of secondary carbonate accumulations.
Telay soils: have less than 15 percent coarse fragments in the A horizon (loess cap).
GEOGRAPHIC SETTING: The climate has cool moist summers and cold moist winters.
Parent material: residuum, slope alluvium and colluvium derived from sandstone, tuff, basalt, and breccia.
Landform: mesas, mountain slopes, and hills.
Slopes: 3 to 40 percent.
Elevation: 9,900 to 11,500 feet.
Mean annual air temperature: 31 to 38 degrees F.
Mean annual precipitation: 29 to 45 inches
Driest months: May and June.
Wettest months: July and August.
Frost-free period: 40 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Behanco and Haycamp soils. Behanco soils have mollic epipedons. Haycamp soils have less than 35 percent rock fragments and fine particle-size control sections.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for timber production and wildlife habitat. Logged areas are also used for livestock grazing. Native vegetation is Engelmann's spruce and subalpine fir, grouse whortleberry, and nodding brome.
DISTRIBUTION AND EXTENT: Southwestern Colorado, LRR E, MLRA 48A. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Ouray Soil Survey Area, Colorado, 1998. The typical pedon is in the adjacent Animas-Dolores Soil Survey Area.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 2 to 13 inches (A and E horizons).
Cambic horizon: The zone from 13 to 40 inches (Bw1, Bw2, and Bw3 horizons).
Particle-size control section: The zone from 12 to 42 inches (part of the E, the Bw1, Bw2, Bw3, and part of the BC horizon).
The mottled colors are due to variation within the parent material. The superactive CEC activity class is presumed for this series based on the general trend indicated by lab data throughout this region. The range of colors in the E horizon includes both albic and non-albic colors; it has not yet been determined which is typical. The original concept of this series is in material derived from sandstone.
Keys to Soil Taxonomy: Series classified according to Eighth Edition, 1998
ADDITIONAL DATA: This typical pedon was sampled by the National Soil Survey Lab, Soil Survey Sample Number S86-CO-033-005. Field study of several pedons determined that this soil should have an average clay content in the particle-size control section of 20 to 35 percent. There are many soft rock fragments that are ground up and turned into sand in preparing the sample.