LOCATION ACREE COEstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Typic Argiustolls
TYPICAL PEDON: Acree loam - rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 10 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very friable; few scattered pebbles; neutral; gradual smooth boundary. (5 to 12 inches thick)
Bt1--10 to 14 inches; brown (7.5YR 5/2) clay loam, dark brown (7.5YR 3/2) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, very friable; few faint clay films on faces of peds; 5 percent pebbles; neutral; clear smooth boundary. (3 to 6 inches thick)
Bt2--14 to 27 inches; reddish brown (5YR 5/4) clay, reddish brown (5YR 4/4) moist; moderate medium angular blocky structure parting to moderate fine angular blocky; hard firm, very plastic; many distinct clay films on faces of peds, and on the inside of root channels and pores; 5 percent pebbles; slightly alkaline; clear wavy boundary. (4 to 24 inches thick)
Btk--27 to 34 inches; reddish brown (5YR 5/4) clay loam, reddish brown (5YR 4/4) moist; moderate medium angular blocky structure; hard firm, very plastic; common faint clay films on faces of peds; 10 percent cobbles; calcium carbonate is segregated as few weakly cemented nodules; violently effervescent; moderately alkaline; gradual wavy boundary. (3 to 10 inches thick)
Bk--34 to 60 inches; light reddish brown (5YR 6/4) heavy clay loam, reddish brown (5YR 5/4) moist; massive; very hard, firm, very plastic; 10 percent cobbles; calcium carbonate is segregated as common weakly cemented nodules and in thin seams and streaks; visible secondary calcium carbonate decreases with depth; violently effervescent; moderately alkaline.
TYPE LOCATION: Eagle County, Colorado; 2,600 feet north and 1,900 feet east of the southwest corner, sec. 11, T. 7 S., R. 87 W; USGS Leon quad; lat. 39 degrees 27 minutes 39 seconds N. and long. 107 degrees 04 minutes 42 seconds W., NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture regime: The soils are moist in some part of the moisture control section during the period the soil temperature at depth of 20 inches is above 41 degrees F. Typic ustic regime.
Mean annual soil temperature: 40 to 46 degrees F.
Mean annual summer soil temperature: 50 to 67 degrees F.
Particle-size control section (weighted average): 35 to 50 percent clay and 0 to 35 percent rock fragments ranging from gravel to stones.
Thickness of the mollic epipedon: 8 to 16 inches
Depth to secondary calcium carbonate: 12 to 40 inches
Depth to the base of the Bt horizon: 15 to 40 inches
A horizon:
Hue: 5YR through 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma of 2 or 3 dry or moist
Reaction: neutral or slightly alkaline (pH 6.6 to 7.8).
Bt horizon:
Hue: 10R through 5YR (7.5YR in the upper part)
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 2 to 5 dry or moist
Texture: clay, clay loam, or silty clay loam
Reaction: neutral or slightly alkaline (pH 6.6 to 7.8).
Bk horizon:
Hue: 10R through 5YR
Value: 4 to 6 dry, 4 or 5 moist.
Calcium carbonate equivalent: 5 to 14 percent.
COMPETING SERIES: These are the Absarokee, Bearpaw, Brolliar, Delson, Herm, Morapos, Nortez, Peninsula, Pramiss, Reget, Ricot, Tamaneen, Tomasaki, Tukuhnik and Work series.
Absarokee, Brolliar, and Nortez soils have a lithic contact between 20 to 40 inches below the surface.
Bearpaw and Tamaneen soils have hues of 10YR or yellower.
Delson and Tomasaki soils lack accumulations of secondary calcium carbonate.
Herm and Morapos soils have hue of 7.5YR or yellower in the lower part of the argillic horizon.
Peninsula soils have a calcic horizon.
Pramiss and Reget soils have a paralithic contact between depths of 20 to 40 inches below the surface.
Ricot soils have a lithologic discontinuity with outwash.
Tukuhnik soils have a lithic contact with siltstone between 40 and 60 inches.
Work soils have hue of 7.5YR or yellower in the lower part of the Bk horizon.
GEOGRAPHIC SETTING: Acree soils are on alluvial fans and valley sides. Slope range from 3 to 25 percent. The soils formed in reddish brown calcareous clayey slope alluvium derived from redbed sandstones and shales. Elevations range from 6,500 to 8,200 feet. At the type location the average annual precipitation ranges from 16 to 18 inches with nearly equal monthly distribution. The mean annual temperature is 38 to 42 degrees F, the mean summer temperature is 61 degrees F. The frost-free season is about 90 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dollard and Showalter soils. Dollard soils are on mountain sides and ridges and are moderately deep to shale. Showalter soils are on alluvial fans and valley sides and have a clayey-skeletal particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; slow permeability.
USE AND VEGETATION: These soils are used principally as rangeland or cropland. Native vegetation is mainly sagebrush, oakbrush, serviceberry, and native grasses with scattered pinyon and juniper trees.
DISTRIBUTION AND EXTENT: Mountainous areas of central Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: The Aspen-Gypsum Area, Colorado, 1982.
REMARKS: Diagnostic horizons and features recognized in the pedon are:
Mollic epipedon: The zone from 0 to 14 inches. (A and Bt1)
Argillic horizon: The zone from 10 to 34 inches. (Bt1, Bt2, and Btk)
Accumulations of secondary calcium carbonate: The zone from 27 to 60 inches. (Btk and Bk)
Particle-size control section extends from 10 to 30 inches.