LOCATION PLUGHAT COEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Calcidic Haplustalfs
TYPICAL PEDON: Plughat silt loam, on a northwest facing, convex, 2 percent slope in grass at an elevation of 5630 feet. (Colors are for dry soil unless otherwise noted.) When described on July 6, 1989 the soil was dry from 0 to 48 inches.
A--0 to 3 inches (0 to 8 cm); brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; moderate very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; noneffervescent; slightly alkaline (pH 7.6); clear smooth boundary. (2 to 5 inches thick)
Bt1--3 to 6 inches (8 to 15 cm); brown (10YR 5/3) silty clay loam, brown (10YR 4/3) moist; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; few distinct patchy clay films on faces of peds; very slightly effervescent; slightly alkaline (pH 7.8); clear smooth boundary.
Bt2--6 to 13 inches (15 to 33 cm); pale brown (10YR 6/3) silty clay loam, brown (10YR 4/3) moist; moderate fine and medium prismatic structure parting to moderate medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; common very fine roots; common distinct continuous clay films on faces of peds; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (Combined thickness of the Bt horizons is 9 to 15 inches)
Btk--13 to 27 inches( 33 to 69 cm); light yellowish brown (10YR 6/4) silty clay loam, yellowish brown (10YR 5/4) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; extremely hard, very firm, moderately sticky and moderately plastic; common very fine roots; 8.0 percent calcium carbonate equivalent; common distinct patchy clay films on faces of peds; common medium irregular masses of carbonate throughout; violently effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (12 to 16 inches thick)
Bk1--27 to 34 inches ( 69 to 86 cm); very pale brown (10YR 7/4) silt loam, light yellowish brown (10YR 6/4) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; 35.0 percent calcium carbonate equivalent; violently effervescent; moderately alkaline (pH 8.3); abrupt smooth boundary
2Bk2--34 to 48 inches (86 to 122 cm); very pale brown (10YR 7/4) loam, light yellowish brown (10YR 6/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; 18.0 percent calcium carbonate equivalent; violently effervescent; 14 percent gravel; moderately alkaline (pH 8.3); abrupt irregular boundary. (Combined thickness of the Bk horizons is 17 to 36 inches)
2R--48 inches (86 cm); hard Dakota sandstone.
TYPE LOCATION: Las Animas County, Colorado; about 0.75 miles north of highway 160 and 15 miles northeast of Branson, Colorado; located about 1,750 feet south and 550 feet west of the northeast corner of sec. 15, T. 33 S., R. 57 W.; Box Ranch USGS quad; lat. 37 degrees 10 minutes 17 seconds N. and long. 103 degrees 46 minutes 39 seconds W., NAD 1927.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is moist April through June and intermittently moist July and August; Ustic moisture regime bordering on Aridic.
Mean annual soil temperature: 50 to 54 degrees F
Mean annual summer soil temperature: 68 to 74 degrees F
Depth to lithic contact: 40 to 60 inches to sandstone
Depth to the base of the argillic horizon: 23 to 36 inches
Depth to secondary calcium carbonate: 2 to 10 inches
Depth to calcic horizon: 21 to 31 inches
Particle-size control section (weighted average):
Clay content: 27 to 35 percent
Sand content: 5 to 25 percent, with less than 15 percent fine sand and coarser
Rock fragments: 0 to 5 percent gravel
A horizon:
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 2 or 3
Texture: silt loam, loam
Clay content: 18 to 27 percent
Rock fragments: 0 to 5 percent
Calcium carbonate equivalent: 0 to 2 percent
Reaction: neutral or slightly alkaline
An AB horizon is present in some pedons
Bt1 horizon:
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4
Texture: silty clay loam, clay loam
Clay content: 27 to 35 percent
Calcium carbonate equivalent: 0 to 5 percent
Reaction: slightly alkaline or moderately alkaline
Bt2 horizon:
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4
Texture: silty clay loam, clay loam
Clay content: 27 to 35 percent
Calcium carbonate equivalent: 2 to 10 percent
Reaction: slightly alkaline or moderately alkaline
Btk horizon:
Hue: 7.5YR or 10YR
Value: 6 or 7 dry, 4 to 6 moist
Chroma: 3 to 6
Texture: silty clay loam, clay loam
Clay content: 27 to 35 percent
Rock fragments: 0 to 5 percent
Calcium carbonate equivalent: 5 to 15 percent
Reaction: moderately alkaline or strongly alkaline
Bk horizons:
Hue: 7.5YR or 10YR
Value: 6 to 8 dry, 5 to 7 moist
Chroma: 3 to 6
Texture: silt loam, loam
Clay content: 18 to 27 percent
Rock fragments: 0 to 15
Calcium carbonate equivalent: 15 to 40 percent
Reaction: moderately alkaline or strongly alkaline
COMPETING SERIES: These are the
Acantilado,
Cahona,
Canina,
Kucu and
Villegreen series.
Acantilado, Cahona, Canina and Kucu soils are very deep.
Villegreen soils have a lithic contact at depths of 20 to 40 inches.
GEOGRAPHIC SETTING:
Parent material: loess and residuum derived from sedimentary materials
Landform: plains and interfluves
Slopes: 1 to 4 percent
Elevation: 5,000 to 6,500 feet
Mean annual temperature: 50 to 53 degrees F
Mean annual precipitation: 14 to 16 inches
Precipitation pattern: continental
wettest months: April through August
driest months: November through February
Frost-free period: 130 to 155 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Baca, Calemore, Villegreen, and Wiley series. The Baca soils average more than 35 percent clay and are on nearly level areas. The Calemore soils have a mollic epipedon and are on footslopes and toeslopes. The Villegreen soils have a lithic contact at depths of 20 to 40 inches and are on backslopes. The Wiley soils are very deep and are on footslopes, toeslopes, and summits.
DRAINAGE AND PERMEABILITY: Well drained, slow runoff, moderately slow permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. Native vegetation is mainly blue grama, western wheatgrass, green needlegrass, bottlebrush squirreltail, red threeawn, and winterfat
DISTRIBUTION AND EXTENT: Southeastern plains, Colorado; LRR G, MLRA 67; This soil is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado.
SERIES ESTABLISHED: Las Animas County, Colorado, Las Animas County Area soil survey area, Colorado. The name was taken from a mesa in the area.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 3 to 23 inches. (Bt1, Bt2 and part of the Btk horizons)
Ochric epipedon: The zone from 0 to 3 inches. (A horizons)
Argillic horizons: The zone from 3 to 27 inches. (Bt1, Bt2, and Btk horizons)
Calcic horizon: The zone from 27 to 48 inches. (Bk1 and Bk2 horizons)
Lithic contact: The contact with sandstone at 48 inches. (R horizons)
Other features:
Remarks: This soil series was originally a bedrock substratum phase of the Wiley series.
The assignment of the cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.
Modified by Lee Neve in January 2002 in order to make format changes.
WAW 2/2007 updated competing series.
Taxonomic Version: Keys to Soil Taxonomy Tenth Edition, 2006
ADDITIONAL DATA: