LOCATION CARRANZA CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Pachic Haploxerolls
TYPICAL PEDON: Carranza gravelly clay loam - on a northeast facing slope of 4 percent at an elevation of 400 feet under soft chess, foxtail fescue, filaree, and wild oats. (Colors are for dry soil unless otherwise stated. When described on June 21, 1978, the soil was dry to 2 inches and slightly moist below).
A--0 to 12 inches; brown (7.5YR 4/2) gravelly clay loam, dark brown (7.5YR 3/2) moist; moderate medium and coarse subangular blocky structure; hard, friable, slightly sticky and moderately plastic; common very fine roots; common very fine and few fine tubular pores; very few thin pressure faces; 23 percent clay content; 20 percent gravel 2 to 40 mm in size; neutral (ph 7.0); clear smooth boundary. (11 to 21 inches thick)
Bt--12 to 22 inches; brown (7.5YR 4/2) clay loam, dark brown (7.5YR 3/2) moist; weak medium and coarse subangular blocky structure; hard, friable, slightly sticky and moderately plastic; common very fine roots; common very fine and few fine tubular pores; few thin clay films on faces of peds and line pores; 29 percent clay content; 10 percent gravel 2 to 40 mm in size; neutral (pH 7.0); clear wavy boundary. (9 to 12 inches thick)
C1--22 to 30 inches; brown (7.5YR 4/2) gravelly sandy clay loam, dark brown (7.5YR 3/4) moist; weak medium and coarse subangular blocky structure; hard, friable, slightly sticky and moderately plastic; few very fine roots; common very fine tubular pores; few thin clay films bridging sand grains; 30 percent gravel and cobbles; neutral (pH 7.0); clear wavy boundary.
C2--30 to 38 inches; strong brown (7.5YR 4/6) gravelly sandy clay loam, brown (7.5YR 4/4) moist; massive; hard, friable, slightly sticky and moderately plastic; few very fine roots; common very fine tubular pores; few thin clay films bridging sand grains; 25 percent gravel and cobbles; neutral (pH 7.2); gradual smooth boundary. (Combined thickness of the C horizons is 15 to 24 inches).
2C3--38 to 60 inches; yellowish brown (10YR 5/4) extremely gravelly sandy clay loam, brown (10YR 4/3) moist; massive; hard, friable, slightly sticky and slightly plastic; no roots; no pores; 75 percent gravel and cobbles; neutral (pH 7.2).
TYPE LOCATION: Merced County, California; approximately 4 miles west northwest of the community of Santa Nella, about 80 feet west of dirt road; 350 feet south and 50 feet east of the northwest corner of section 34, T. 9 S., R. 8 E., MDB&M; Latitude 37 degrees, 06 minutes, 54 seconds north and Longitude 121 degrees, 05 minutes, 12 seconds west; USGS San Luis Dam Topographic Quadrangle, NAD 27.
RANGE IN CHARACTERISTICS: The upper boundary of the extremely gravelly layer is at a depth of 35 to 57 inches. The moisture control section is moist throughout from about December 15 to May 15 and dry throughout from about June 15 to November 1 most years. The soil temperature is warmer than 47 degrees F from February 1 to December 30. The mean annual soil temperature is about 62 degrees F. The climate is semiarid with hot dry summers and cool moist winters. Reaction is neutral in the solum and neutral to slightly alkaline in the substratum.
The A horizon has color of 10YR 4/2, 5/3 or 7.5YR 4/2. Moist color is 10YR 3/2, 3/3 or 7.5YR 3/2. Texture is gravelly loam or gravelly clay loam. Clay content is 20 to 35 percent. Gravel content is 15 to 25 percent.
The Bt horizon has color of 10YR 4/2, 4/4, 5/2, 5/4; 7.5YR 4/2, 4/4, 5/2 or 5/4. Moist color is 10YR 3/2, 3/3 or 7.5YR 3/2. Texture is clay loam, gravelly loam, or gravelly clay loam. Clay content is 25 to 35 percent. Gravel content is 5 to 25 percent.
The C horizon has color of 10YR 5/3, 5/4; 7.5YR 4/2, 4/4, 4/6, 5/4 or 5/6. Moist color is 10YR 4/3, 4/4; 7.5YR 3/4, 4/4 or 4/6. Texture is gravelly sandy clay loam or gravelly loam. Clay content is 25 to 35 percent. Gravel content is 15 to 35 percent.
The 2C3 horizon is extremely gravelly sandy clay loam, extremely gravelly loamy sand, or extremely gravelly loam. Clay content is 10 to 30 percent. Gravel content is 60 to 90 percent. Some pedons are stratified.
COMPETING SERIES: These are the Agueda, Conejo, Gazos, Reward, Salinas and Westfan series. Agueda soils, in alluvium from calcareous sedimentary rocks, have carbonates throughout the profile. Conejo soils (MLRA 14, 17), on alluvial fans and stream terraces, are not gravelly in any part of the profile. Gazos soils (MLRA 15, 20), on hills, have a lithic contact at a depth of 20 to 40 inches. Reward soils (MLRA 15), on uplands, are effervescent and have a lithic contact at a depth of 40 to 60 inches. Salinas soils, on alluvial plains, fans and terraces, have carbonates below a depth of 22 to 36 inches and have less than 15 percent rock fragments. Westfan soils (MLRA 17), on relict alluvial fans, have Btk and Ck horizons and have less than 15 percent rock fragments.
GEOGRAPHIC SETTING: Carranza soils are on alluvial fans in foothills and adjacent to terraces in the central valley. Slope is 0 to 8 percent. These soils formed in mixed alluvium dominantly from sedimentary rock sources. Elevation is 150 to 1,800 feet. The climate is semiarid with hot dry summers and cool moist winters. The mean annual precipitation is about 9 to 13 inches. Mean January temperature is 44 degrees F; mean July temperature is 76 degrees F; and mean annual temperature is about 61 degrees F. Frost-free season is 200 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bapos, Los Banos, Vernalis, and Woo soils. Bapos and Los Banos soils, on terraces and fan remnants, have an argillic horizon and a fine particle-size control section. Vernalis soils, on alluvial fans and flood plains, have carbonates at a depth of 7 to 36 inches and do not have a mollic epipedon. Woo soils, on alluvial fans, are effervescent and have a mollic epipedon less than 20 inches thick.
DRAINAGE AND PERMEABILITY: Well drained; low to high runoff; moderate over slow permeability or moderate over rapid permeability depending on the kind of substratum.
USE AND VEGETATION: These soils are used for irrigated apricots, cantaloupes and cotton. Where irrigation water is not available, they are used for livestock grazing and nonirrigated small grain crops.
DISTRIBUTION AND EXTENT: These soils occur in alluvial fans of the Central San Joaquin Valley and in small low elevation valleys of the Coast Range foothills. They are not extensive. MLRA 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Merced County, California, 1984.
REMARKS: These soils were formerly included with and mapped as Esparto and Sorrento soils in the Los Banos Area, series 1939 report. They are being differentiated from Esparto soils by having a mollic epipedon and no argillic horizon, and from Sorrento soils by having a thick (Pachic) mollic epipedon and are noneffervescent. pH determined by colorimetric method using Thymol Blue and Hellige-Truog Triplex indicators. Texture determined by modified Bouyoucos method. Presence of carbonates determined by 10 percent HC1 solution. Organic matter assumed to be greater than 1 percent.