LOCATION ADABOI ID

Established Series
Rev. MEJ/ALH/CLM/RWL
07/2011

ADABOI SERIES

The Adaboi series consists of very deep, well drained soils with low saturated hydraulic conductivity that formed in slope alluvium and colluvium from silty lacustrine deposits. Slopes range from 1 to 35 percent in foothills. The average annual precipitation is about 15 inches and the average annual temperature is about 49 degrees F.

TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Argixerolls

TYPICAL PEDON: Adaboi silt loam -- on a 12 percent slightly concave northwest-facing slope at 3,540 feet elevation in rangeland. When described on October 4, 1994, the soil was dry throughout. (Colors are for air-dry soil unless otherwise noted.)

A1--0 to 2 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak thin platy structure parting to moderate fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine and fine, common medium and coarse roots; many very fine and fine irregular pores; 2 percent gravel; slightly acid (pH 6.5); clear smooth boundary. (2 to 4 inches thick)

A2--2 to 9 inches; grayish brown (10YR 5/2) silt loam, very dark brown (10YR 2/2) moist; moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine, common medium and coarse roots; common very fine and fine tubular pores; 2 percent gravel; slightly acid (pH 6.5); clear smooth boundary. (2 to 11 inches thick)

Bt1--9 to 13 inches; brown (10YR 5/3) silty clay loam, dark brown (10YR 3/3) moist; strong fine subangular blocky structure; hard, friable, slightly sticky and moderately plastic; common very fine and fine, few medium and coarse roots; common very fine and fine tubular pores; few distinct clay films on faces of peds and in pores; 2 percent gravel; neutral (pH 6.8); clear wavy boundary. (3 to 10 inches thick)

Bt2--13 to 20 inches; brown (10YR 5/3) silty clay loam, dark brown (10YR 3/3) moist; strong medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine and fine, few medium and coarse roots; common very fine and fine tubular pores; common distinct clay films on faces of peds and in pores; about 25 percent of ped faces covered with bleached silt grains; 2 percent gravel; neutral (pH 6.7); abrupt wavy boundary. (3 to 10 inches thick)

Bt/E--20 to 25 inches; (Bt material - 65% of horizon) brown (10YR 5/3) silty clay loam, brown (10YR 4/3) moist; strong medium and coarse subangular blocky structure; very hard, friable, slightly sticky and moderately plastic; common very fine and fine, few medium and coarse roots; common very fine and fine tubular pores; few distinct clay films on faces of peds and in pores; 2 percent gravel; neutral (pH 6.6); (E material) light gray (10YR 7/2) silt loam, grayish brown (10YR 5/2) moist; moderate fine granular structure; soft, friable, slightly sticky and slightly plastic; abrupt smooth boundary. (3 to 12 inches thick)

Btb1--25 to 43 inches; brown (10YR 5/3) silty clay, dark brown (10YR 3/3) moist; moderate medium and coarse prismatic structure; very hard, firm, very sticky and very plastic; few very fine and fine roots; few very fine and fine tubular pores; many distinct clay films on faces of peds and in pores; about 40 percent of ped faces covered with bleached silt grains; 5 percent gravel; neutral (pH 7.0); gradual wavy boundary. (12 to 22 inches thick)

Btb2--43 to 67 inches; pale brown (10YR 6/3) clay, brown (10YR 4/3) moist; strong medium and coarse prismatic structure; very hard, firm, very sticky and very plastic; few very fine and fine roots; few very fine and fine tubular pores; many distinct clay films on faces of peds and in pores; 5 percent gravel; neutral (pH 7.2).

TYPE LOCATION: Boise County, Idaho; about 7.5 miles south and 3 miles west of Horseshoe Bend; 600 feet north and 250 feet east of the southwest corner of section 31, T.6 N., R.2 E.; USGS Pearl Quadrangle; Latitude - 43 degrees, 48 minutes, 33 seconds N. and Longitude - 116 degrees, 16 minutes, 22 seconds W., NAD83.

RANGE IN CHARACTERISTICS:
Mollic epipedon thickness - 20 to 42 inches
Depth to bedrock - 60 inches or more
Reaction - slightly acid or neutral
Moisture control section - dry 60 to 90 consecutive days following the summer solstice
Particle-size control section - 35 to 60 percent clay, less than 15 percent medium and coarse sand; 0 to 5 percent rock fragments
Average annual soil temperature - 50 to 52 degrees F.

A horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Clay content - 20 to 27 percent
Rock fragments - 0 to 5 percent gravel

Bt horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Texture - SICL or CL
Clay content - 35 to 40 percent
Rock fragments - 0 to 5 percent gravel

Bt/E horizon
- Bt material (same as above) - greater than 50 percent of horizon
- E material
Value - 6 or 7 dry, 4 or 5 moist
Chroma -2 or 3 dry or moist
Clay content - 23 to 27 percent
Rock fragments - 0 to 5 percent gravel

Btb horizon
Value - 5 through 7 dry, 3 or 4 moist
Chroma - 3 or 4 dry or moist
Texture - SIC or C
Clay content - 40 to 60 percent
Rock fragments - 0 to 10 percent gravel

COMPETING SERIES: These are the Aradaran, Ayette, Darow, Forsgren, Gimmi, Hann, Karney, Kuck, McDesh, Montour, Tub and Ukiah series. Aradaran and Hann soils do not have Glossic or buried argillic horizons. Ayette soils are 40 to 60 inches deep to a paralithic contact and have a mollic epipedon 10 to 20 inches thick. Darow, Gimmi, Karney, Kuck and Ukiah soils are moderately deep to a paralithic contact. Forsgren soils are calcareous at depths of 40 to 55 inches. McDesh soils are 20 to 40 inches deep to a lithic contact. Montour soils are calcareous at depths above 40 inches. Tub soils have secondary carbonates at a depth of 18 to 37 inches.

GEOGRAPHIC SETTING: Adaboi soils are on fan remnants, hill backslopes and footslopes at elevations of 3,200 to 3,800 feet. These soils formed in slope alluvium and colluvium from silty lacustrine deposits. Slopes range from 1 to 35 percent. Average annual precipitation is 14 to 16 inches. Average annual temperature is 48 to 50 degrees F. Frost-free period is 120 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Meclo and Crawley soils. Meclo soils are moderately deep to a paralithic contact. Crawley soils are shallow to a paralithic contact. The Meclo and Crawley soils are on convex geomorphic positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; low saturated hydraulic conductivity.

USE AND VEGETATION: Adaboi soils are used mainly for rangeland. Small areas are used for irrigated hayland/pasture. Native vegetation is xeric big sagebrush and bluebunch wheatgrass.

DISTRIBUTION AND EXTENT: West-central Idaho. MLRA 10. Adaboi 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: This revision changes the taxonomic subgroup from "Pachic" to "Vertic" due to re-calculation of linear extensibility.

Diagnostic horizons and features recognized in this pedon:
Mollic epipedon - zone from the surface to 20 inches (A1, A2, Bt1, and Bt2 horizons)
Argillic horizon - zone from 9 to 67 inches (Bt1, Bt2, Bt/E, Btb1, and Btb2 horizons)
Glossic horizon - zone from 20 to 25 inches (Bt/E horizon)
Linear extensibility - 6.0 or more in the zone from the soil surface to 40 inches (assumed)
Particle-size control section - zone from 9 to 29 inches
Soil moisture regime - xeric

National Cooperative Soil Survey
U.S.A.