LOCATION BOLFAR CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, thermic Cumulic Endoaquolls
TYPICAL PEDON: Bolfar clay loam - on a slope of 1 percent in a cultivated cotton field at 105 feet elevation. (Colors are for dry soil unless otherwise stated. When described on November 18, 1976, the soil was moist throughout).
Apk--0 to 11 inches; dark gray (10YR 4/1) clay loam, black (10YR 2/1) and very dark gray (10YR 3/1) moist; strong medium granular structure; hard, friable, moderately sticky and moderately plastic; few fine and medium roots; few very fine and fine tubular and interstitial pores; strongly effervescent, carbonates disseminated and segregated as fine irregular concretions; moderately alkaline (pH 8.0); abrupt smooth boundary. (8 to 14 inches thick)
Ak--11 to 25 inches; dark gray (10YR 4/1) and grayish brown (10YR 5/2) clay loam, black (10YR 2/1) moist; common medium faint dark grayish brown (10YR 4/2) masses of iron accumulations moist; moderate medium prismatic structure; hard, friable, moderately sticky and moderately plastic; few fine and medium roots; common very fine and fine tubular pores; common moderately thick clay films on faces of peds and staining mineral grains; strongly effervescent, carbonates disseminated and segregated as fine irregular concretions; moderately alkaline (pH 8.0); clear smooth boundary. (10 to 16 inches thick)
Btk1--25 to 29 inches; gray (10YR 6/1) clay loam, dark gray (10YR 4/1) moist; common fine distinct white (10YR 8/1) masses of iron accumulations, common fine distinct light brownish gray (10YR 6/2) masses of iron accumulations moist; moderate fine and medium prismatic structure; hard, friable, moderately sticky and moderately plastic; few medium roots; common very fine tubular pores; common moderately thick clay films on faces of peds and line pores; slightly effervescent, carbonates disseminated and segregated as few fine irregular concretions; moderately alkaline (pH 8.0); clear wavy boundary. (4 to 12 inches thick)
Btk2--29 to 41 inches; olive gray (5Y 4/2) and olive (5Y 5/3) loam, olive gray (5Y 4/2) and very dark grayish brown (2.5Y 3/2) moist; few fine distinct olive yellow (5Y 6/8) iron depletions, few medium prominent strong brown (7.5YR 5/8) masses of iron accmulations moist; moderate medium angular blocky structure; hard, friable, moderately sticky and moderately plastic; few medium roots; common very fine and fine tubular pores; common thin clay films on faces of peds; slightly effervescent, carbonates disseminated and segregated as few fine irregular concretions; moderately alkaline (pH 8.0); clear wavy boundary. (6 to 12 inches thick)
C1--41 to 53 inches; olive (5Y 5/3) and olive gray (5Y 4/2) loam, olive gray (5Y 4/2) and dark olive gray (5Y 3/2) moist; common fine prominent yellowish brown (10YR 5/6) masses of iron accumulation, common fine and medium prominent yellowish brown (10YR 5/8) moist; weak medium angular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine and fine tubular and interstitial pores; few thin clay films on faces of peds; slightly effervescent with disseminated carbonates; moderately alkaline (pH 8.0); clear wavy boundary. (6 to 15 inches thick)
C2--53 to 60 inches; gray (5Y 6/1) loam, greenish gray (5GY 6/1) moist; common large prominent yellowish brown (10YR 5/6) masses of iron accumulation, common large prominent yellowish brown (10YR 5/8) masses of iron accumulation moist; massive; slightly hard, friable, moderately sticky and moderately plastic; common very fine and fine tubular and interstitial pores; moderately alkaline (pH 8.0).
TYPE LOCATION: Merced County, California; approximately 7 miles north of the city of Dos Palos, 2,100 feet east of the Hutchins and Elgin Roads intersection, 200 feet south of Hutchins Road and 2.9 miles west of the San Joaquin River; 1,100 feet east and 300 feet south of the northwest corner of section 11, T. 10 S., R. 12 E. MDB&M; Latitude 37 degrees, 04 minutes, 57 seconds north and Longitude 120 degrees, 37 minutes, 51 seconds west; USGS Delta Ranch Quadrangle, NAD 27.
RANGE IN CHARACTERISTICS: These soils are saturated with stagnant water for at least a few days. The thickness of the mollic epipedon ranges from 24 to 30 inches depending on the land leveling. The 10 to 40 inch control section averages from 27 to 35 percent clay but individual layers have clay content of 18 to 35 percent. Organic matter content is 1 to 3 percent in the upper 24 to 30 inches and decreases regularly. Organic matter content is less than 0.5 percent at a depth of 50 inches. Some pedons are noneffervescent below a depth of 20 inches.
The A horizon has color of 10YR 3/1, 4/1, 4/2, 5/2; 2.5Y 3/2 or 5/2. Moist color is 10YR 2/1, 3/1, 3/2; 2.5Y 3/2 or N 2/0. Texture is loam, sandy clay loam or clay loam. Reaction is slightly alkaline or moderately alkaline.
The Btk horizon has color of 10YR 6/1; 7.5YR 5/4; 2.5Y 6/2, 5/2; 5Y 5/4, 6/1 or 6/2. Moist color is 10YR 3/3, 4/1, 4/2, 4/4, 5/3; 5Y 3/2, 4/1, 4/2, 4/3, 5/2, 5/5; 2.5Y 3/2, 4/2 or 5/2. Redoximorphic features are distinct or prominent. Texture is loam, sandy clay loam or clay loam. Typically, the electrical conductivity of the saturation extract is less than 2.0 decisiemens per meter and the sodium adsorption ratio is less than 6.
The C horizon has color of 5Y 4/2, 4/3, 5/3, 6/1; 2.5Y 4/2, 6/2 or 10YR 6/3. Moist color is 10YR 4/2, 4/4; 5Y 3/1, 3/2, 4/1, 4/2, 4/3, 5/2, 5/3, 5/6; 2.5Y 3/2, 4/2, 4/4, 5/4; 5GY 5/1, 6/1; 5BG 5/1 or 5G 5/1. Texture is loam. Some pedons have texture of sandy loam, sandy clay loam, or clay loam and are stratified.
COMPETING SERIES: This is the Gambogy (CA) series. Gambogy soils (MLRA 17), on alluvial fans and flood plains, do not have segregated carbonates in the the A and B horizons.
GEOGRAPHIC SETTING: Bolfar soils are in valley basins and on flood plains. Slope is 0 to 2 percent. The soils formed in mixed alluvium dominantly from granitic rocks. Much of this soil has been land leveled, but was hummocky in its natural landscape. Elevation is 35 to 110 feet. The climate is semiarid with hot dry summers and cool moist winters. The mean annual precipitation is 10 to 12 inches. The mean annual temperature is 60 to 62 degrees F. The frost-free season is 210 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dospalos, Elnido, Escano, Kesterson and Palazzo soils. Dospalos soils, on valley basins, has a fine particle-size control section. Elnido soils, on channels, flood plains, basin floors and valley basins, have a coarse-loamy particle-size control section. Escano soils, on valley basins, have a calcic horizon at a depth of 25 to 39 inches. Kesterson soils, on valley basins, have a natric horizon. Palazzo soils, on flood plains and basin floors, have organic matter that decreases irregularly with depth, have a mollic epipedon less than 24 inches thick, and are not calcareous at depths of 10 to 20 inches.
DRAINAGE AND PERMEABILITY: Poorly drained; negligible to low runoff; moderately slow permeability. These soils were previously very poorly drained and ponded with stagnant water for extended periods during winter and spring months and are now ponded for periods of 2 to 7 days from December to February. The water table is now 3 to 5 feet December through March. They are now artifically drained or have had their water source intercepted. They are protected from major flooding by large flood control levees and reservoirs. Where not protected, flooding is common January through March.
USE AND VEGETATION: Most of these soils are cultivated and irrigated. They are principally used for field crops and vegetable production with small acreages of orchards and pastures. The remainder of these soils are used for annual range.
DISTRIBUTION AND EXTENT: These soils occur near the San Joaquin River in the central part of the San Joaquin Valley of California. They are moderately 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 surveyed as the Temple series in the Los Banos Area, series 1939 report. These soils are being differentiated by having a thick mollic epipedon which is not characteristic of the Temple series. pH determined by colorimetric method using Thymol Blue and Hellige-Truog Triplex indicators. Texture determined by Bouyoucos method. SAR determined by versinate method.
Runoff terminology adjusted 4/96 to adjective criteria of the Soil Survey Manual, 10/93
CEC/Clay ratio estimated from similar soils with laboratory data in the W. Stanislaus Soil Survey Area.
ADDITIONAL DATA: NSSL pedon S87CA-019-016 (taxadjunct-not calcareous) and S91CA-099-001 (partial pedon).