LOCATION HESS IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, isotic, frigid Vitrandic Argixerolls
TYPICAL PEDON: Hess ashy loam, forested -- on a northwest-facing slope of 40 percent at 5,400 feet elevation. When described on October 3, 1994, the soil was dry throughout. (Colors are for air-dry soil unless otherwise noted.)
Oi--0 to 1 inch; undecomposed and partially decomposed forest litter.
A1--1 to 4 inches; dark grayish brown (10YR 4/2) ashy loam, very dark brown (10YR 2/2) moist; moderate fine and medium granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine, few medium and coarse roots; many very fine and fine irregular pores; 5 percent gravel, 5 percent paragravel; moderately acid (pH 5.9); clear smooth boundary. (1 to 5 inches thick)
A2--4 to 10 inches; brown (10YR 4/3) paragravelly ashy loam, very dark brown (10YR 2/2) moist; weak medium platy structure parting to moderate fine subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine, few medium and coarse roots; common very fine and fine irregular pores; 5 percent gravel, 10 percent paragravel; moderately acid (pH 6.0); clear wavy boundary. (4 to 10 inches thick)
BA--10 to 15 inches; brown (10YR 4/3) paragravelly ashy loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine, few medium and coarse roots; common very fine and fine irregular pores; about 20 percent of ped surface covered with siltans; 5 percent gravel, 10 percent paragravel; slightly acid (pH 6.1); clear smooth boundary. (0 to 8 inches thick)
2Bt1--15 to 20 inches; brown (10YR 4/3) paragravelly clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; hard, very friable, moderately sticky and moderately plastic; few very fine, fine and medium roots; common very fine and fine tubular pores; few distinct clay films on faces of peds and in pores; about 60 percent of ped surface covered with siltans; 5 percent gravel, 10 percent paragravel, 2 percent paracobbles; slightly acid (pH 6.1); gradual wavy boundary. (3 to 10 inches thick)
2Bt2--20 to 29 inches; dark yellowish brown (10YR 4/4) paragravelly clay loam, dark yellowish brown (10YR 3/4) moist; strong medium subangular blocky structure; hard, friable, very sticky and very plastic; few very fine, fine and medium roots; common very fine and fine, few medium tubular pores; common distinct clay films on faces of peds and in pores; about 30 percent of ped surface covered with siltans; 5 percent gravel, 10 percent paragravel, 2 percent paracobbles; slightly acid (pH 6.1); clear smooth boundary. (5 to 10 inches thick)
2Bt3--29 to 38 inches; reddish brown (2.5YR 4/4) very paragravelly clay loam, dark reddish brown (2.5YR 3/4) moist; weak fine and medium prismatic structure parting to strong fine and medium subangular blocky; very hard, firm, very sticky and very plastic; few very fine and fine roots; few very fine and fine tubular pores; common distinct clay films on faces of peds and in pores; 10 percent gravel, 35 percent paragravel, 2 percent paracobbles; slightly acid (pH 6.2); gradual wavy boundary. (5 to 10 inches thick)
2Bt4--38 to 44 inches; reddish brown (2.5YR 5/4) and strong brown (7.5YR 5/6) very paragravelly clay loam, reddish brown (2.5YR 4/4) moist; strong fine subangular blocky structure; very hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; few very fine and fine tubular pores; common prominent clay films on faces of peds and in pores; 10 percent gravel, 40 percent paragravel, 5 percent paracobbles; slightly acid (pH 6.2); gradual wavy boundary. (5 to 10 inches thick)
2R--44 inches; slightly weathered consolidated ash (tuff).
TYPE LOCATION: Boise County, Idaho; about 2 miles south and 3 miles east of Banks; 500 feet north and 2,600 feet east of the southwest corner of section 2, T.8 N., R.3 E.; USGS Banks Quadrangle; Latitude - 44 degrees, 03 minutes, 12 seconds N. and Longitude - 116 degrees, 04 minutes, 06 second W.; NAD 83.
RANGE IN CHARACTERISTICS:
Mollic epipedon thickness - 10 to 20 inches
Depth to bedrock - 40 to 60 inches
Reaction - slightly acid or moderately acid
Base saturation (10 to 30 inches) - 50 to 75 percent
Particle-size control section - 25 to 35 percent clay; 0 to 15 percent rock fragments
Moisture control section - dry for 45 to 75 consecutive days following the summer solstice
Average annual soil temperature - 43 to 47 degrees F.
A horizon
Value - 3 or 4 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Clay content - 20 to 27 percent
Rock fragments - 0 to 15 percent gravel
Pararock fragments - 0 to 15 percent paragravel
Volcanic glass content - 5 to 20 percent
Acid oxalate extract A1+1/2 Fe - 0.4 to 1.2 percent
2Bt1 horizon
Value - 4 or 5 dry, 3 or 4 moist
Chroma - 2 or 3 dry or moist
Texture - L or CL
Clay content - 24 to 30 percent
Rock fragments - 0 to 15 percent gravel
Pararock fragments - 0 to 15 percent paracobbles, 0 to 15 percent paragravel
2Bt2, 2Bt3 and 2Bt4 horizons
Hue - 5YR through 10YR
Value - 4 or 5 dry, 3 or 4 moist
Chroma - 4 through 6 dry or moist
Clay content - 27 to 35 percent
Rock fragments - 0 to 15 percent gravel
Pararock fragments - 0 to 5 percent paracobbles, 5 to 50 percent paragravel
COMPETING SERIES: These are the Bly, Lidos, Melhorn, Raycreek (T), Salcreek (T) and Vangoe (T) series. Bly soils have mollic epipedons 20 to 30 inches thick. Lidos soils are very deep and have buried E and Bt horizons. Melhorn soils are very deep. Raycreek soils are 20 to 40 inches deep to bedrock. Salcreek soils are very deep and have rock fragments of glacial till origin. Vangoe soils have mollic epipedons 20 to 33 inches thick.
Runyon (T) soils have a similar classification with mixed mineralogy and 20 to 40 inches to a paralithic contact (vesicular basalt).
GEOGRAPHIC SETTING: Hess soils are on mountain slopes and hill backslopes and footslopes at elevations of 3,850 to 5,900 feet. These soils formed in colluvium and residuum from basalt and tuff mixed with volcanic ash in the upper part. Slopes range from 4 to 65 percent. The average annual precipitation is 26 to 32 inches. The average annual temperature is 41 to 45 degrees F. The frost-free period is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Lidos and the Cleymor and Klicker series. Cleymor soils are clayey on hill footslopes. Klicker soils are loamy-skeletal on similar geomorphic positions. Lidos soils are on similar geomorphic positions.
DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; moderately slow permeability.
USE AND VEGETATION: Hess soils are used mainly for timber production and woodland grazing. Native vegetation is Douglas-fir, ponderosa pine and mallow ninebark.
DISTRIBUTION AND EXTENT: West-central Idaho. MLRA 43b. Hess soils are not extensive.
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 1 to 20 inches (A1, A2, BA and 2Bt1 horizons)
Vitrandic feature - zone from 1 to 15 inches (A1, A2 and BA horizons)
Argillic horizon - zone from 15 to 44 inches (2Bt1, 2Bt2, 2Bt3 and 2Bt4 horizons)
Particle-size control section - zone from 15 to 35 inches
Soil moisture regime - xeric
All depths to diagnostic horizons and features within the range of characteristics are measured from the top of the first mineral layer.