LOCATION CAMPO COEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Paleargids
TYPICAL PEDON: Campo silt loam - grassland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 10 centimeters (0 to 4 inches); light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; soft, very friable, slightly sticky, slightly plastic; noncalcareous; neutral (pH 6.8); clear smooth boundary. (8 to 15 centimeters (3 to 6 inches) thick)
A2--10 to 13 centimeters (4 to 5 inches); light gray (10YR 7/2) silt loam, grayish brown (10YR 5/2) moist; moderate thin platy structure that parts to fine granules; soft, very friable, slightly sticky, slightly plastic; noncalcareous; neutral (pH 6.8); abrupt smooth boundary. (0 to 8 centimeters (0 to 3 inches) thick)
Bt--13 to 51 centimeters (5 to 20 inches); brown (10YR 5/3) silty clay, brown (10YR 4/3) moist; strong medium prismatic structure that parts to fine angular blocks; slightly hard, very friable, sticky, plastic; peds are extremely hard; thin wax-like coatings on the faces of peds and wax-like coatings and fillings in root channels and pores; wax-like rims around the entrance to some soil pores; discontinuous gray coatings of bleached sand and silt grains on the faces of some peds in the upper part of this horizon; noncalcareous; slightly alkaline (pH 7.4); gradual smooth boundary. (15 to 91 centimeters (6 to 36 inches) thick)
Bk--51 to 61 centimeters (20 to 24 inches); pale brown (10YR 6/3) silty clay loam, brown (10YR 5/3) moist; weak medium prismatic structure that parts to medium and fine angular and subangular blocks; slightly hard, very friable, slightly sticky, slightly plastic; peds are extremely hard; few thin glossy coatings on the faces of some peds and discontinuous glossy coatings on the inside of root channels and pores; visible secondary calcium carbonate occurring as concretions and in thin seams and streaks; calcareous; moderately alkaline (pH 8.4); gradual wavy boundary. (8 to 25 centimeters (3 to 10 inches) thick)
Ck--61 to 152 centimeters (24 to 60 inches); very pale brown (10YR 7/3) silt loam, pale brown (10YR 6/3) moist; massive; hard, very friable, slightly sticky, slightly plastic; visible secondary calcium carbonate occurring as concretions, in thin seams and streaks, and in finely divided forms; the amount of calcium carbonate decreases with depth; calcareous; moderately alkaline (pH 8.4).
TYPE LOCATION: Baca County, Colorado; approximately 35 meters (115 feet) west and 12 meters (40 feet) north of SE corner of Sec. 33, T. 31 S., R. 43 W.
RANGE IN CHARACTERISTICS:
Depth to uniformly calcareous material: 15 to 76 centimeters (6 to 30 inches) not shallower than the upper 8 centimeters (3 inches) of the Bt horizon.
Depth of the argillic horizon: 30 to 102 centimeters (12 to 40 inches)
Depth to continuous secondary carbonate and/or sulfate: 38 to 102 centimeters (15 to 40 inches) (not strong enough to qualify as calcic or gypsic horizons)
ESP: remains constant or increases with depth, 0 to 15 percent in the solum but possibly exceeding 15 percent in the Ck horizon.
Majority of subhorizons color: hue of 7.5 YR or yellower above 127 centimeters (50 inches)
Rock fragments: 0 to 5 percent by volume in the solum and C horizon above 127 centimeters (50 inches) (mainly 1 to 8 centimeters (1/2 to 3 inches) in diameter)
Thin discontinuous A2 horizons present but are absent in some pedons.
A horizon:
Hue: 5Y to 7.5YR
Value: 5 to 7 dry, 3 to 6 moist
Chroma: 1 to 4
Reaction: neutral or slightly alkaline (l:5 dilution unbuffered organic dye).
Bt horizon:
Hue: 5Y to 7.5YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 1 to 6
Texture: silty clay or clay
Clay content: 35 to 60 percent
Silt content: 20 to 60 percent
Sand content: 5 to 40 percent, less than 15 percent being fine or coarser sand.
Reaction: neutral to moderately alkaline (l:5 dilution unbuffered organic dye).
C horizon:
Hue: 5Y to 7.5YR
Texture: silt loam or silty clay loam
Clay content: 18 to 35 percent
Silt content: 25 to 65 percent
Sand content: 5 to 40 percent, less than 35 percent being fine or coarser sand.
Reaction: moderately or strongly alkaline (l:5 dilution unbuffered organic dye).
Calcium carbonate equivalent: fine earth ranges from about 3 to 15 percent.
COMPETING SERIES: These are the
Gooding,
Mahala,
Phing,
Pyrolake,
Sorf,
Twickenham, and
Verdico.
Gooding soils have a duripan of less than 152 centimeters (60 inches).
Mahala, Sorf and Verico soils have bedrock at less than 102 centimeters (40 inches).
Phing and Pyrolake soils have an albic horizon (E horizon).
Twickenham soils are dry in all parts of the moisture control section for one-half to three-fourths of the time when the soil temperature is above 5 degrees C (41 degrees F).
GEOGRAPHIC SETTING:
Parent material: eolian material or silty alluvium
Landform: upland flats or alluvial fans
Slopes typically range from about 0 to 6 percent or more.
Mean annual precipitation: 25 to 43 centimeters (10 to 17 inches) (peak periods in the spring and early summer months)
Mean annual temperature: 11 degrees C (51 degrees F)
Mean summer temperature: 23 degrees C (74 degrees F)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Baca and
Wiley soils.
Baca soils lack an abrupt textural boundary between the A and B horizons.
Wiley soils lack an abrupt textural boundary, have less than 35 percent clay in the argillic horizon, and are calcareous at shallower depths.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Runoff: low to medium
Saturated Hydraulic Conductivity: moderately low to low
USE AND VEGETATION: Ares are used as rangeland and dry or irrigated cropland. Native vegetation is blue grama, western wheat, cactus, and sage.
DISTRIBUTION AND EXTENT: Eastern Colorado and Wyoming in MLRA 69. The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Western Baca County Soil Erosion District, 1940.
REMARKS: Last updated by the state 4/73.
Updated by MLRA Office-5 on 1/11/2000. Formatted to semeitab and removed MLRA 67 by request from Colorado.