LOCATION DOUBLEDIA IDEstablished Series
TYPICAL PEDON: Doubledia silty clay loam -- on a 12 percent slightly convex north-facing slope at 4,240 feet elevation in rangeland. When described on July 11, 1994, the soil was dry to 5 inches and slightly moist below. (Colors are for air-dry soil unless otherwise noted.)
A--0 to 3 inches; dark grayish brown (10YR 4/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; weak thin platy structure parting to strong fine granular; hard, friable, moderately sticky and moderately plastic; many very fine and fine, common medium and coarse roots; many very fine and fine irregular pores; cracks filled with granular material; neutral (pH 6.9); abrupt smooth boundary. (2 to 6 inches thick)
Bt--3 to 6 inches; grayish brown (10YR 5/2) clay, very dark grayish brown (10YR 3/2) moist; weak fine prismatic structure parting to strong fine subangular blocky; extremely hard, firm, very sticky and very plastic; many very fine and fine, common medium and coarse roots; common very fine and fine tubular pores; common faint clay films on faces of peds and in pores; cracks filled with granular material; slightly acid (pH 6.5); clear wavy boundary. (2 to 11 inches thick)
Btss1--6 to 11 inches; grayish brown (10YR 5/2) clay, very dark grayish brown (10YR 3/2) moist; moderate fine prismatic structure; extremely hard, very firm, very sticky and very plastic; common very fine, fine, few medium roots; common very fine and fine tubular pores; common distinct clay films on faces of peds and in pores; few intersecting slickensides; cracks 1 to 10 mm wide; about 10 percent of faces of peds covered with bleached silt grains; neutral (pH 6.7); gradual wavy boundary. (4 to 9 inches thick)
Btss2--11 to 21 inches; pale brown (10YR 6/3) clay, brown (10YR 4/3) moist; strong medium and coarse prismatic structure; extremely hard, very firm, very sticky and very plastic; few very fine and fine roots; common very fine and fine tubular pores; many distinct clay films on faces of peds and in pores; common intersecting slickensides; common wedge shaped aggregates oriented at 40 to 50 degrees from horizontal at lower part of horizon; 1 percent fine black (10YR 2/1) dry, manganese concretions; cracks 1 to 15 mm wide; neutral (pH 6.6); clear broken boundary. (4 to 15 inches thick)
B't--21 to 25 inches; light gray (2.5Y 7/2) clay loam, grayish brown (2.5Y 5/2) moist; moderate fine prismatic structure parting to strong fine and medium subangular blocky; hard, firm, moderately sticky and moderately plastic; few very fine and fine roots; common very fine and fine tubular pores; few distinct clay films on faces of peds and in pores; cracks 1 to 15 mm wide; neutral (pH 7.0); gradual wavy boundary. (0 to 4 inches thick)
B'tss1--25 to 34 inches; pale brown (10YR 6/3) paragravelly clay, brown (10YR 4/3) moist; strong medium and coarse prismatic structure; extremely hard, very firm, very sticky and very plastic; few very fine and fine roots; common very fine and fine tubular pores; many distinct clay films on faces of peds and in pores; common intersecting slickensides; common wedge shaped aggregates oriented at 40 to 50 degrees from horizontal at lower part of horizon; 1 percent fine black (10YR 2/1) dry, manganese concretions; cracks 1 to 15 mm wide; about 20 percent paragravel; neutral (pH 7.1); discontinuous wavy boundary. (5 to 19 inches thick)
B'tss2--34 to 41 inches; pale brown (10YR 6/3) very paragravelly clay, brown (10YR 5/3) moist; strong fine and medium subangular blocky structure; extremely hard, very firm, very sticky and very plastic; few very fine and fine roots; common very fine and fine tubular pores; few distinct clay films on faces of peds and in pores; cracks 1 to 15 mm wide; about 50 percent paragravel; slightly alkaline (pH 7.4); abrupt boundary. (0 to 10 inches thick)
Crk--41 to 60 inches; stratified silty lacustrine deposits that have less than 5 percent calcium carbonate on horizontal and vertical bedding faces and in pockets.
TYPE LOCATION: Boise County, Idaho; about 5.5 miles south and 2 miles west of Horseshoe Bend; 2,300 feet east and 1,700 feet south of the northwest corner of section 20, T. 6 N., R. 2 E.; USGS Cartwright Canyon Quadrangle; Latitude - 43 degrees, 50 minutes, 45 seconds N. and Longitude - 116 degrees, 14 minutes, 47 seconds W.; NAD 83.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 10 to 20 inches
Depth to paralithic contact - 40 to 60 inches
Surface cracks - 1 mm to 5 cm wide; open from July through October in most years
Moisture control section - dry for 60 to 90 consecutive days following the summer solstice
Average annual soil temperature - 47 to 53 degrees F.
A horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Clay content - 27 to 35 percent
Rock fragments - 0 to 5 percent gravel
Reaction - slightly acid or neutral
Bt and Btss horizons
Value - 5 or 6 dry, 2 through 4 moist
Chroma - 2 through 4 dry or moist
Texture - SIC or C
Clay content - 40 to 60 percent
Rock fragments - 0 to 5 percent gravel
Pararock fragments - 0 to 10 percent paragravel
Slickensides - few to common intersecting in Btss horizons
Wedge shaped aggregates - few to common in Btss horizons
Reaction - moderately acid through neutral
B't and B'tss horizons
Hue - 2.5Y or 10YR
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 2 through 4 dry or moist
Texture - SICL, CL, SIC or C
Clay content - 35 to 60 percent
Rock fragments - 0 to 5 percent gravel
Pararock fragments - 0 to 50 percent paragravel
Slickensides - few to common intersecting in B'tss horizons
Wedge shaped aggregates - few to common in B'tss horizons
Reaction - neutral or slightly alkaline
COMPETING SERIES: These are the Mchandy, Ravendale, Thorncreek and Yad series. Mchandy soils are deep to an indurated duripan. Ravendale soils are very deep and have carbonates at 40 to 60 inch depth. Thorncreek soils are deep to a lithic contact and have Bq horizons above the bedrock. Yad soils are very deep.
GEOGRAPHIC SETTING: Doubledia soils are nearly level to steep on fan remnants, hill backslopes, footslopes and toeslopes, and on landslides at elevations of 2,600 to 4,650 feet. Slopes range from 2 to 50 percent. These soils formed in colluvium and residuum from lacustrine deposits. The average annual precipitation is 14 to 20 inches. The average annual temperature is 45 to 51 degrees F. The frost-free period is 90 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Breadloaf, Hann and Siphonlake soils. Breadloaf soils are moderately deep to a paralithic contact. Hann soils are very deep. Siphonlake soils are deep to a paralithic contact and have fine-loamy particle size control sections. These soils occur on similar geomorphic positions.
DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; very slow permeability.
USE AND VEGETATION: Doubledia soils are used mainly for rangeland. Small areas are used for irrigated hayland/pasture. Native vegetation is xeric big sagebrush, antelope bitterbrush, biscuitroot, Idaho fescue and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: West-central Idaho. MLRA 10. Doubledia soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Boise County Area, Idaho, Parts of Ada and Boise Counties, 2005.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon - zone from the surface to 11 inches (A, Bt and Btss1 horizons)
Argillic horizon - zone from 3 to 41 inches (Bt1, Btss1, Btss2, B't, B'tss1 and B'tss2 horizons)
Particle-size control section - zone from 3 to 23 inches
Paralithic contact - at 41 inches ( Crk horizon)
Cracks - 1 to 15 mm wide extending from the soil surface to the paralithic contact
Soil moisture regime - xeric
ADDITIONAL DATA: Reference sample no. S94ID-015-002 (NSSL pedon 95Z162)