LOCATION MONASTERIO ID

Established Series
Rev. JR/ALH/CLM
09/2019

MONASTERIO SERIES

The Monasterio series consists of moderately deep, well drained soils with moderate permeability that formed in residuum and slope alluvium from vitric tuff and breccia. Monasterio soils are on structural benches and foothills. Slopes range from 1 to 20 percent. The average annual precipitation is about 380 mm, and the average annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Ashy-skeletal, glassy, frigid Vitrandic Argixerolls

TYPICAL PEDON: Monasterio gravelly ashy sandy loam -- on a west-facing slope of 5 percent, in native rangeland at 1,770 meters elevation. The surface has about 2 percent stone cover. (When described on July 11, 1979, the soil was dry to 41 cm and slightly moist below. Colors are for air dry soil unless otherwise stated.)

A1--0 to 10 cm; dark grayish brown (10YR 4/2) gravelly ashy sandy loam, black (10YR 2/1) moist; moderate fine and medium granular structure; slightly hard, very friable; many fine and very fine roots; many fine and very fine interstitial pores; 15 percent gravel, 1 percent stones; moderately acid (pH 5.7); clear smooth boundary. (5 to 15 cm thick)

A2--10 to 20 cm; dark grayish brown (10YR 4/2) ashy sandy loam, black (10YR 2/1) moist; weak fine subangular blocky structure parting to moderate fine and medium granular; slightly hard, very friable; many fine and very fine, common medium roots; many fine and very fine interstitial pores; 10 percent gravel; neutral (pH 6.6); clear smooth boundary. (0 to 20 cm thick)

BA--20 to 28 cm; brown (10YR 4/3) gravelly ashy sandy loam, very dark brown (10YR 2/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine, common medium and coarse roots; many fine tubular and interstitial pores; neutral (pH 6.8); 15 percent gravel; clear smooth boundary. (0 to 18 cm thick)

Bt1--28 to 43 cm; dark yellowish brown (10YR 4/4) very gravelly ashy sandy loam, dark brown (10YR 3/3) moist; moderate medium and fine subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common fine, very fine and medium roots; common fine and medium tubular and interstitial pores; very few thin clay films on faces of peds; 30 percent gravel, 10 percent cobbles; neutral (pH 6.9); clear wavy boundary. (13 to 20 cm thick)

Bt2--43 to 64 cm; yellowish brown (10YR 5/4) very cobbly ashy sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium prismatic structure parting to strong medium angular blocky; very hard, firm, moderately sticky and moderately plastic; common very fine roots; common very fine and fine tubular pores; common moderately thick clay films on faces of peds and rocks; 30 percent gravel, 15 percent cobbles; neutral (pH 6.9); clear wavy boundary. (0 to 43 cm thick)

Btq--64 to 71 cm; yellowish brown (10YR 5/4) extremely stony ashy sandy clay loam, brown (7.5YR 4/4) moist; moderate fine angular blocky structure; very hard, firm, moderately sticky and moderately plastic; few very fine roots; few fine tubular pores; common thin clay films on faces of peds, in pores, and on rocks; 35 percent gravel, 25 percent cobbles, 20 percent stones; secondary silica fills interstices and opalized pendants are common on undersides of rock fragments; neutral (pH 7.0); abrupt wavy boundary. (3 to 15 cm thick)

R--71 cm; weathered flow-breccia.

TYPE LOCATION: Owyhee County, Idaho; about 3 miles west and 14 miles north of Riddle; 1,000 feet east and 300 feet south of the northwest corner of section 18, T. 12 S., R. 3 E.; USGS Turner Table 7.5 minute topographic quadrangle; latitude 42 degrees 23 minutes 23 seconds N and longitude 116 degrees 09 minutes 17 seconds W; WGS84 Decimal Degrees 42.3897222 latitude, -116.1547222 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring and dry late June through mid-October; aridic soil moisture regime bordering on xeric.
Mollic epipedon thickness: 18 to 43 cm.
Base saturation in some part above 76 cm: 50 to 75 percent.
Depth to bedrock: 50 to 100 cm.
Average annual soil temperature: 5 to 8 degrees C.
Average summer soil temperature: 16 to 19 degrees C.

Particle-size control section - Clay content: Average 18 to 32 percent.
Rock fragments: Average 35 to 60 percent.

A horizons
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 1 to 3 dry or moist.
Reaction (pH): Moderately acid to neutral.
Rock fragments: 5 to 35 percent.
Volcanic glass content: 50 to 70 percent.

Bt horizons
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 2 to 4 moist.
Chroma: 2 to 4 dry or moist.
Textures: Sandy clay loam or clay loam.
Texture modifiers: Very cobbly or very gravelly.
Reaction (pH): Slightly acid or neutral.
Volcanic glass content: 45 to 70 percent.

Btq horizon
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 2 to 6 dry or moist.
Textures: Sandy clay loam or sandy loam.
Texture modifiers: Extremely cobbly or extremely stony.
Clay content: 18 to 32 percent.
Rock fragments: 60 to 90 percent.
Reaction (pH): Slightly acid or neutral.
Volcanic glass content: 30 to 50 percent.

COMPETING SERIES: This is the Eep series. Eep soils are very deep.

GEOGRAPHIC SETTING: Monasterio soils are nearly level to rolling on structural benches and foothills at elevations of 1,463 to 1,981 meters. Slopes range from 1 to 20 percent. The soils formed in residuum and slope alluvium from vitric tuff and basal flow-breccias. The climate is cool and moist in the winter and warm and dry in summer. Average annual precipitation ranges from 330 to 460 mm, and average annual temperature is 4 to 7 degrees C. The frost-free period is 60 to 95 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Avtable, Cleavage, Fuego, Saturday, Sharesnout, Thacker, Wickahoney and Yatahoney soils. Avtable, Cleavage, and Wickahoney soils are less than 50 cm deep to bedrock and on more exposed, higher landscape positions. Fuego soils lack argillic horizons and are on similar landscape positions. Saturday soils are loamy-skeletal and are on rocky ridges. Sharesnout soils have more than 35 percent clay in the control section and are on similar landscape positions. Thacker and Yatahoney soils have indurated duripans between 50 to 100 cm and are on lower fan terraces.

DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate permeability.

USE AND VEGETATION: Monasterio soils are used mainly for rangeland and wildlife habitat. The dominant natural vegetation is mountain big sagebrush, Idaho fescue, antelope bitterbrush, and bluebunch wheatgrass.

DISTRIBUTION AND EXTENT: Southwestern Idaho. This series is extensive. MLRA 25.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Owyhee County Area, Idaho, 1992.

REMARKS: The classification was changed from Ultic to Vitrandic and the particle-size from loamy-skeletal to ashy-skeletal in 1991.

Diagnostic horizons and other features recognized in this pedon:
Mollic epipedon - The zone from the soil surface to 43 cm (A1, A2, BA, and Bt1 horizons).
Argillic horizon - The zone from 28 to 71 cm (Bt1, Bt2, and Btq horizons).
Particle-size control section - The zone from 28 to 71 cm (Bt1, Bt2, and Btq horizons).

ADDITIONAL DATA: NSSL pedon # 81P-568.

National Cooperative Soil Survey
U.S.A.