LOCATION STROUPE NM+COEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, mixed, superactive, mesic Aridic Argiustolls
TYPICAL PEDON: Stroupe extremely stony loam--grassland. (Colors are for dry
soil unless otherwise noted.)
A--0 to 4 inches; dark brown (7.5YR 4/3) stony loam, dark brown (7.5YR 3/3) moist; moderate very fine granular structure; soft, very friable; about 60 percent cobbles, stones and gravel; neutral; clear smooth boundary. (3 to 7 inches thick)
Bw--4 to 7 inches; dark brown (7.5YR 4/3) very stony loam, dark brown (7.5YR 3/3) moist; moderate, fine subangular blocky structure; hard, very friable; few thin clay films on surfaces of peds; about 35 percent cobbles, stones and gravel; slightly alkaline; clear smooth boundary. (3 to 7 inches thick)
Bt1--7 to 12 inches; brown (7.5YR 5/4) stony clay, brown (7.5YR 4/4) moist; weak fine prismatic structure parting to moderate, fine subangular blocky; hard, firm, sticky, and plastic; many prominent clay films on surfaces of peds; about 30 percent cobbles, stones and gravel; slightly alkaline; gradual wavy boundary. (4 to 8 inches thick)
Bt2--12 to 20 inches; brown (7.5YR 5/4) extremely stony clay, brown (7.5YR 4/4) moist; moderate fine subangular blocky structure; hard, slightly sticky and plastic; few small concretions and films of calcium carbonate on surfaces of peds; common distinct clay films on surfaces of peds and on rock fragments; about 70 percent stones, cobbles, and gravel; strongly effervescent; moderately alkaline; gradual wavy boundary. (6 to 12 inches thick)
C/Cr--20 to 30 inches; fractured igneous bedrock with material similar to horizon above in the cracks; slightly alkaline. (0 to 12 inches thick)
R--30 inches; hard igneous bedrock.
TYPE LOCATION: Torrance County, New Mexico; E1/2 NW1/4, section 31, T.1N.,
R.12E.
RANGE IN CHARACTERISTICS:
Soil Moisture: An ustic soil moisture regime bordering on aridic. The soil moisture control section is dry in some or all parts for more than 200 days but less than 250 cumulative days in normal years.
Mean annual soil temperature: 47 to 52 degrees F.
Depth to lithic contact: 20 to 40 inches
Depth to argillic horizon: 6 to 14 inches
Particle-size control section (weighted average)
Clay content: 35 to 50 percent
Coarse Fragments: 20 to 70 percent stones and cobbles, 5 to 30 percent pebbles; averages 55 percent
CEC/clay ratio: 0.60 to 0.90
A and Bw horizons
Hue: 7.5YR, 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3
Texture: clay loam, clay
Clay content: 35 to 45 percent
Coarse fragments: 35 to 70 percent igneous and sandstone cobbles, stones, pebbles
Base saturation: 100 percent
Calcium carbonate equivalent: 0 to 1 percent
Effervescence: none to very slight
Reaction: neutral or slightly alkaline
Bt horizon
Hue: 5YR, 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6
Texture: clay loam, sandy clay, clay
Clay content: 40 to 50 percent
Clay films: few to many, faint to prominent, on surfaces of peds, coating coarse fragments and in pore linings
Coarse fragments: 20 to 70 percent stones and cobbles, 5 to 30 percent pebbles
Base saturation: 100 percent
Calcium carbonate equivalent: 0 to 12 percent
Identifiable secondary carbonate: none to few, very fine to medium, on surfaces of peds
Effervescence: none to strong
Reaction: neutral or slightly alkaline
COMPETING SERIES: These are the Goldust (NM), Parquat (NM), Tafoya (NM), and Veldkamp (CO) series. Similar soils are the Trock, Majada, Montosa, and Salas series.
Goldust,
Parquat, and
Veldkamp soils: do not have a lithic contact within 60 inches of the surface
Tafoya soils: have a lithic contact between 40 and 60 inches of the surface.
Trock,
Majada, Montosa, and
Salas soils: have a loamy-skeletal particle size family
GEOGRAPHIC SETTING:
Parent material: colluvium derived from igneous and sandstone bedrock
Landform: mountain sideslopes, footslopes and shoulder slopes
Slope: 5 to 70 percent
Mean annual air temperature: 45 to 50 degrees F.
Mean annual precipitation: 16 to 20 inches
Frost-free period: 120 to 150 days
Elevation: 5,500 to 7,800 feet
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Capillo, Fuera, Laporte, Mirabal, Supervisor, and Witt series.
Capillo soils: have a frigid temperature regime
Fuera soils: do not have a mollic epipedon and have a frigid temperature regime
Laporte soils: do not have an argillic horizon and have bedrock within 20 inches of the surface
Mirabal soil: do not have an argillic horizon and have a frigid temperature regime
Supervisor soils: have a cryic temperature regime
Witt soils: do not have a mollic epipedon
DRAINAGE AND PERMEABILITY: Well drained. Permeability is slow. Runoff is high on 5 to 20 percent slopes and very high on slopes greater than 20 percent.
USE AND VEGETATION: Mostly used for rangeland and recreation. Sideoats grama, blue grama, cacti, yucca, pinyon pine, juniper and few ponderosa pine are present in the plant community.
DISTRIBUTION AND EXTENT: Foothill of mountainous areas of New Mexico, Colorado, and possibly Wyoming, the series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Pueblo Area, Colorado, 1974.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 7 to 20 inches. (Bt horizon)
Mollic epipedon: 0 to 7 inches. (A and Bw horizons)
Argillic horizon: 7 to 20 inches. (Bt horizon)
Lithic contact: The contact with igneous bedrock at 30 inches
The assignment of the cation-exchange activity class is inferred from lab data from soil survey areas in the surrounding regions.
Additional data: none
Taxonomic version: Second Edition, 1999