LOCATION TABLE MOUNTAIN CO+WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Pachic Haplustolls
TYPICAL PEDON: Table Mountain loam - grassland. (Colors are for dry soil unless otherwise noted).
A--0 to 10 centimeters (0 to 4 inches); brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; common fine roots; neutral; abrupt smooth boundary. (8 to 25 centimeters (3 to 10 inches) thick)
Bw--10 to 56 centimeters (4 to 22 inches); grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure parting to moderate medium subangular blocky; hard, very friable, slightly sticky and slightly plastic; common fine roots; few thin clay films on faces of peds; neutral; clear wavy boundary. (46 to 76 centimeters (18 to 30 inches) thick)
BC--56 to 86 centimeters (22 to 34 inches); pale brown (10YR 6/3) loam, grayish brown (10YR 5/2) moist; weak medium prismatic structure; hard, very friable, slightly sticky and slightly plastic; few fine roots; few thin clay films in pores and root channels; neutral; clear irregular boundary. (0 to 36 centimeters (0 to 14 inches) thick)
Ck--86 to 152 centimeters (34 to 60 inches); very pale brown (10YR 7/3) loam, brown (10YR 5/3) moist; weak coarse prismatic structure; slightly hard, very friable, slightly plastic; few fine roots; fine filaments and threads of calcium carbonate; violently effervescent; moderately alkaline.
TYPE LOCATION: Washington County, Colorado; 61 meters (200 feet) west and 396 meters (1,300 feet) north of the southeast corner of Sec. 2, T. 3 S., R. 54 W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 10 to 12 degrees C. (49 to 53 degrees F.)
Depth to uniformly calcareous material: 0 to 102 centimeters (0 to 40 inches)
Exchangeable sodium: 0 to 15 percent in most subhorizons of the control section
mollic epipedon: 51 to 127 centimeters (20 to 50 inches) thick
Continuous concentrated horizons of visible secondary calcium carbonate and/or sulfate: 51 to 102 centimeters (20 to 40 inches)
Control section: typically loam, sandy clay loam, or light clay loam
Particle-size control section: (weighted average)
Clay content: 18 to 35 percent
Silt content: 20 to 55 percent
Sand content: 20 to 55 percent, less than 35 percent being fine or coarser sand
Rock fragments: 0 to 15 percent in the control section and dominantly are 1 to 25 centimeters (1/2 to 10 inches) in diameter
Hues of subhorizons above 102 centimeters (40 inches): 7.5YR or yellower
Some pedons have a few faint mottles with the chroma of both matrix and mottles exceeding 2.
A horizon:
Hue: 5Y to 7.5YR
Value: 4 or 5, 2 or 3 moist
Chroma: 1 to 3
Texture: loam
Reaction: slightly acid to slightly alkaline
Bw horizon:
Hue: 5Y to 7.5YR
Value: 3 to 7, or 3 to 6 moist
Chroma: 1 to 6
Texture: loam
Reaction: slightly acid to slightly alkaline
C horizon:
Hue: 5Y to 7.5YR
Texture: loam
Reaction: moderately alkaline or strongly alkaline
Calcium carbonate accumulation: 2 to 14 percent
The C horizon of some pedons is stratified with gravelly sandy loam or silty clay loam.
COMPETING SERIES: These are the
Bonilla,
Davis and
Whiskey series.
Bonilla and Davis soils are moist more than 1/2 the time the soil temperature is 5 degrees C. (41 degrees F.) or higher.
Whiskey soils are on stream terraces at elevations of 1768 to 2134 meters (5,800 to 7,000 feet).
GEOGRAPHIC SETTING:
Landform: alluvial fans, terraces, concave drains and old floodplains
Slopes: 0 to 15 percent
Parent material thick, calcareous, medium to moderately fine textured materials derived from sedimentary and metamorphic rocks
Mean annual precipitation: 36 to 41 centimeters (14 to 16 inches) with peak periods of precipitation occurring in the spring and early summer months
Mean annual temperature: 9 degrees C. (48 degrees F.)
Mean summer temperature: 21 degrees C. (69 degrees F.)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Fort Collins and
Kim soils.
Fort Collins soils have an ochric epipedon and an argillic horizon.
Kim soils have an ochric epipedon and are calcareous above a depth of 10 inches.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well-drained
Runoff: medium to low
Saturated Hydraulic Conductivity: moderately high
USE AND VEGETATION: These soils are used as grazing land and as dry or irrigated cropland.
Native vegetation is blue grama, western wheat, sage, and cactus.
DISTRIBUTION AND EXTENT: Eastern and central Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Brighton Area, Colorado, 1932.
Modified format by LRM in 3/2006 to include metric conversion and change permeability to saturated hydraulic conductivity.