LOCATION MUGATU CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Xeric Argigypsids
TYPICAL PEDON: Mugatu fine sandy loam, 0 to 5 percent slopes, on a stream terrace, under Atriplex and annual grasses at an elevation of 800 feet. (Colors are for dry soil unless otherwise noted. When described on January 13, 1981, the soil was dry throughout.)
A1--0 to 2 inches; light gray (10YR 7/2) fine sandy loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; common very fine tubular and many very fine interstitial pores; slightly effervescent, carbonates disseminated; calcium carbonate equivalent is 1 percent; electrical conductivity is 2.3 decisiemens per meter; sodium adsorption ratio is 1; 1 percent gravel; slightly alkaline (pH 7.7); abrupt smooth boundary. (1 to 5 inches thick)
A2--2 to 10 inches; very pale brown (10YR 7/3) fine sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular and many very fine interstitial pores; strongly effervescent, carbonates disseminated; calcium carbonate equivalent is less than 1 percent; electrical conductivity is 1.0 decisiemens per meter; sodium adsorption ratio is 1; 3 percent gravel; moderately alkaline (pH 8.1); abrupt smooth boundary. (6 to 12 inches thick)
A3--10 to 24 inches; very pale brown (10YR 7/3) fine sandy loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots, common very fine tubular and many very fine interstitial pores; strongly effervescent, carbonates disseminated; calcium carbonate equivalent is 3 percent 2; electrical conductivity is 1.6 decisiemens per meter; sodium adsorption ratio is 2; 5 percent gravel; moderately alkaline (pH 8.2); abrupt smooth boundary. (0 to 16 inches thick)
Bty--24 to 41 inches; light yellowish brown (10YR 6/4) clay loam, yellowish brown (10YR 5/4) moist; moderate medium angular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; many very fine interstitial pores; few moderately thick clay films on faces of peds; strongly effervescent, carbonates disseminated; calcium carbonate equivalent is less than 1 percent; calcium sulfate (gypsum) segregated as many medium irregular threads and soft masses, calcium sulfate (gypsum) content is 19 percent; electrical conductivity is 5.3 decisiemens per meter; sodium adsorption ratio is 8; 6 percent gravel; moderately alkaline (pH 7.9); clear smooth boundary. (15 to 27 inches thick)
2By--41 to 60 inches; very pale brown (10YR 7/3) very gravelly coarse sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; many very fine interstitial pores; strongly effervescent, carbonates disseminated; calcium carbonate equivalent is 2 percent; calcium sulfate (gypsum) content is 1 percent; electrical conductivity is 5.2 decisiemens per meter; sodium adsorption ratio is 7; 37 percent gravel and 2 percent cobbles; moderately alkaline (pH 7.9). (17 to 21 inches thick)
TYPE LOCATION: Fresno County, California; approximately 2 miles south of the junction of Panoche and Silver Creeks, approximately 2,000 feet north and 1,600 feet east of the southwest corner of section 32, T. 15 S., R. 12 E., MDB&M; Latitude 36 degrees, 34 minutes, 47 seconds north and Longitude 120 degrees, 41 minutes, 13 seconds west; USGS Tumey Hills Topographic Quadrangle, NAD 27.
RANGE IN CHARACTERISTICS: The soil is 60 inches or more deep. The mean annual soil temperature is 64 to 67 degrees F. The moisture control section of 8 to 24 inches becomes moist during the latter part of December and stays moist until about the end of March. It is usually dry the rest of the year. The soil temperature is always above 47 degrees F. The particle-size control section averages 27 to 35 percent clay. Reaction is neutral to moderately alkaline.
The A horizon has color of 10YR 5/3, 6/3, 6/4, 7/2, 7/3, 7/4 or 2.5Y 7/2. Moist color is 10YR 4/2, 4/3; 2.5Y 4/2, 5/2 or 5/4. Calcium carbonate equivalent is 1 to 3 percent. Electrical conductivity is 0 to 4 decisiemens per meter. Sodium adsorption ratio is 0 to 5. Gravel content is 0 to 10 percent.
The Bty horizon has color of 10YR 5/4, 6/3, 6/4; 2.5Y 4/2, 5/2 or 5/4. Moist color is 10YR 4/3, 4/4, 5/4; 2.5Y 4/2 or 4/3. Calcium carbonate equivalent is 0 to 5 percent. Calcium sulfate (gypsum) content is 15 to 25 percent. Electrical conductivity is 4 to 8 decisiemens per meter. Sodium adsorption ratio is 5 to 12. Gravel content is 0 to 10 percent.
The 2By horizon has color of 10YR 5/4, 6/3, 6/4, 7/2, 7/3 or 7/4. Moist color is 10YR 4/3, 4/4, 5/3, 5/4, 6/2, 6/3 or 6/4. Calcium carbonate equivalent is 0 to 3 percent. Calcium sulfate (gypsum) content is 1 to 5 percent. Electrical conductivity is 2 to 8 decisiemens per meter. Sodium adsorption ratio is 5 to 12. Gravel content is 15 to 50 percent. Cobble content is 0 to 3 percent.
COMPETING SERIES: There are no competing series at this time.
GEOGRAPHIC SETTING: Mugatu soils are on stream terraces. Slope is 0 to 30 percent. These soils formed in alluvium derived dominantly from sandstone and shale. Elevation is 574 to 1,280 feet. The climate is arid with hot dry summers and cool somewhat moist winters. The mean annual precipitation is 6 to 8 inches. Mean January temperature is about 46 degrees F.; mean July temperature is about 81 degrees F.; mean annual temperature is 62 to 65 degrees F. The frost-free season is 250 to 270 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Grazer, Guijarral, Exclose, Milham, Polvadero, and Belgarra soils. Grazer soils, on hills and mountains, have a fine particle-size control section, and do not have a gypsic horizon. Guijarral soils, on fan remnants, have a coarse-loamy particle-size control section and do not have a gypsic horizon. Exclose soils, on mountains, do not have an argillic horizon or a gypsic horizon. Milham soils, on fan remnants,do not have a gypsic horizon. Polvadero soils, on fan remnants, have natric and calcic horizons, and do not have a gypsic horizon. Belgarra soils, on erosional fan remnants on mountains, have a fine particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained; medium or high runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. The vegetation is mainly red brome, rattail fescue, and saltbush (atriplex).
DISTRIBUTION AND EXTENT: These soils occur on the western edge of the San Joaquin Valley. They are not extensive. MLRA 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Fresno County, California, 2002.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon--The zone from the soil surface to a depth of 24 inches (A1, A2, and A3 horizons).
2. Argillic horizon--The zone from 24 inches to a depth of 41 inches (Bty horizon). This horizon has 34 percent clay and is in a fine-loamy particle size family.
3. Particle size control section-- Is the Argillic horizon, 24 to 41 inches (17 inches thick).
4. Gypsic horizon--The zone from 24 inches to a depth of 41 inches (Bty horizon).
5. Xeric Sub Group--The moisture control section is dry in all parts for less than three-fourths of the time (cumulative). The soil temperature at a depth of 50 centimeters is 5 degrees centigrade or higher and the moisture regime is aridic bordering on a Xeric Regime.
ADDITIONAL DATA: NSSL lab data is available for the Typical Pedon from soil sample number S86CA019-036 (1196-1200). This includes data for selenium content.