LOCATION MCDESH IDEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Argixerolls
TYPICAL PEDON: McDesh loam -- on a north-facing slope of 4 percent at 3,700 feet elevation in rangeland. When described on August 29, 1994, the soil was dry throughout. (Colors are for air-dry soil unless otherwise noted.)
A--0 to 3 inches; brown (10YR 4/3) loam, dark brown (10YR 3/3) moist; moderate thin platy structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine irregular pores; neutral (pH 6.6); clear wavy boundary. (2 to 4 inches thick)
Bt1--3 to 11 inches; brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; moderate very coarse prismatic structure parting to moderate coarse subangular blocky; hard, friable, moderately sticky and moderately plastic; common very fine and fine roots; many very fine and fine tubular pores; common distinct clay films on faces of peds and in pores; cracks less than 5 mm wide; neutral (pH 6.8); gradual wavy boundary. (5 to 10 inches thick)
Bt2--11 to 21 inches; dark yellowish brown (10YR 4/4) clay, dark brown (7.5YR 3/3) moist; moderate fine and medium prismatic structure parting to moderate medium subangular blocky; very hard, firm, very sticky and very plastic; few very fine roots; common very fine and fine tubular pores; many prominent clay films on faces of peds and in pores; 2 percent gravel; cracks less than 5 mm wide; neutral (pH 7.0); clear wavy boundary. (5 to 10 inches thick)
Bt3--21 to 24 inches; yellowish brown (10YR 5/4) clay, brown (7.5YR 4/3) moist; weak medium prismatic structure parting to weak medium subangular blocky; very hard, firm, very sticky and very plastic; few very fine and fine roots; common very fine and fine tubular pores; many prominent clay films on faces of peds and in pores; 2 percent paragravel; neutral (pH 7.2); clear smooth boundary. (0 to 5 inches thick)
R--24 inches; fractured welded tuff.
TYPE LOCATION: Boise County, Idaho; about 1 mile north and 6 miles west of Banks; 100 feet south and 1,400 feet east of the northwest corner of section 29, T.9 N., R.2 E.; USGS Dry Buck Valley Quadrangle; Latitude - 44 degrees, 05 minutes, 39 seconds N. and Longitude - 116 degrees, 15 minutes, 01 seconds W.; NAD 83.
RANGE IN CHARACTERISTICS:
Mollic epipedon thickness - 10 to 40 inches
Depth to bedrock - 20 to 40 inches
Particle-size control section - 35 to 50 percent clay; 0 to 25 percent rock fragments
Moisture control section - dry 60 to 90 consecutive days following the summer solstice
Average annual soil temperature - 47 to 53 degrees F.
A horizon
Hue - 10YR or 7.5YR
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Rock fragments - 0 to 25 percent stones and boulders, 0 to 20 percent cobbles, 0 to 15 percent gravel and 0 to 60 percent total
Bt1 horizon
Hue - 10YR or 7.5YR
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Texture - CL or SICL
Clay content - 27 to 35 percent
Rock fragments - 0 to 5 percent cobbles, 0 to 15 percent gravel and 0 to 15 percent total
Cracks - 1 to 5 mm wide
Bt2 and Bt3 horizons
Hue - 10YR or 7.5YR
Value - 4 or 5 dry, 3 or 4 moist
Chroma - 2 through 4 dry or moist
Texture - C or SIC
Clay content - 40 to 60 percent
Rock fragments - 0 to 5 percent cobbles, 0 to 30 percent gravel and 0 to 35 percent total
Pararock fragments - 0 to 15 percent
Cracks - 0 to 5 mm wide
Reaction - neutral or slightly alkaline
Bq horizons are present in some pedons.
COMPETING SERIES: These are the Ayette, Darow, Forsgren, Gimmi, Hann, Karney, Kuck, Montour, Tub and Ukiah series. Ayette soils are 40 to 60 inches deep to a paralithic contact. 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 and are very deep. Hann soils are very deep. Montour soils are calcareous at depths of 29 to 32 inches and are very deep. Tub soils are very deep and have secondary carbonates at a depth of 18 to 37 inches.
GEOGRAPHIC SETTING: McDesh soils are on structural benches, hill backslopes and footslopes and butte escarpments at elevations of 2,600 to 5,750 feet. These soils formed in slope alluvium and colluvium from basalt and welded tuff. Slopes range from 4 to 65 percent. The average annual precipitation is 13 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 Gwin, Immig and Shafer soils. Gwin soils are shallow and on hill summits and shoulders. Immig soils are clayey-skeletal and on hill backslopes. Shafer soils are moderately deep to a paralithic contact and on hill footslopes.
DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid runoff; slow permeability.
USE AND VEGETATION: McDesh soils are used mainly for rangeland. Native vegetation is xeric big sagebrush, bluebunch wheatgrass and Idaho fescue.
DISTRIBUTION AND EXTENT: West-central Idaho. MLRA 10. McDesh 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 soil:
Mollic epipedon - zone from the soil surface to 21 inches (A, Bt1 and Bt2 horizons)
Argillic horizon - zone from 3 to 24 inches (Bt1, Bt2 and Bt3 horizons)
Lithic contact - at 24 inches (R)
Particle-size control section - zone from 3 to 23 inches
Linear extensibility - 6.0 cm or more exists in the zone from the soil surface to the lithic contact (assumed)
Soil moisture regime - xeric