LOCATION PALAZZO CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Fluvaquentic Endoaquolls
TYPICAL PEDON: Palazzo sandy 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 23, 1976, the soil was moist throughout).
Ap--0 to 14 inches; very dark gray (10YR 3/1) sandy loam, black (10YR 2/1) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; few very fine tubular and interstitial pores; moderately alkaline (pH 8.0); abrupt wavy boundary. (10 to 23 inches thick)
Bg1--14 to 26 inches; grayish brown (2.5Y 5/2) sandy loam, dark grayish brown (2.5Y 4/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; few very fine tubular and interstitial pores; few fine distinct strong brown (7.5YR 5/6) moist redoximorphic concentrations; moderately alkaline (pH 8.0); abrupt wavy boundary. (3 to 23 inches thick)
2Bg2--26 to 41 inches; dark gray (10YR 4/1) clay loam, black (N 2/0) and light olive brown (2.5Y 5/4) moist; strong medium and coarse prismatic structure parting to strong fine and medium angular blocky; hard, friable, moderately sticky and moderately plastic; few very fine roots; common very fine many fine and few medium tubular pores; common (5 percent) thin clay films on peds and in pores; moderately alkaline (pH 8.0); gradual smooth boundary. (6 to 20 inches thick)
2Cg--41 to 60 inches; grayish brown (10YR 5/2) clay loam, very dark grayish brown (2.5Y 3/2) and light yellowish brown (2.5Y 6/4) moist; massive; hard, friable, moderately sticky and moderately plastic; no roots; common very fine, many fine and few medium tubular pores; common (5 percent) thin clay films line pores and bridge sand grains; moderately alkaline (pH 8.0).
TYPE LOCATION: Merced County, California; approximately 8 miles north of the city of Dos Palos, 1 mile north of the intersection of Hutchins and Indiana Roads, 2,200 feet east of Indiana Road and 100 feet south of Wood Slough; 800 feet east and 500 feet north of the southwest corner of section 31, T. 9 S., R. 13 E., MDB&M; Latitude 37 degrees, 05 minutes, 56 seconds north and Longitude 120 degrees, 35 minutes, 41 seconds west; USGS Santa Rita Bridge Topographic Quadrangle, NAD 27.
RANGE IN CHARACTERISTICS: These soils are saturated with stagnant water for at least a few days. They are dry in the upper part of the moisture control section from June through September. The thickness of the mollic epipedon is 10 to 23 inches. Organic matter content decreases irregularly with depth. Electrical conductivity is 0 to 4 decisiemens per meter. Reaction is neutral to moderately alkaline.
The A horizon has color of 10YR 3/1, 3/2, 4/1, 4/2, 5/1, 5/2; 2.5Y 3/2, 4/2, 5/2; N 4/0 or N 5/0. Moist color is 10YR 2/1, 2/2, 3/1, 3/2 or 2.5Y 3/2. Organic matter content is 1 to 3 percent. Clay content is 10 to 18 percent.
The Bg horizon has color of 10YR 5/2, 5/3, 6/2, 6/3, 7/2, 7/3; 2.5Y 5/2, 6/2 or 7/2. Moist color is 10YR 4/2, 5/3, 6/1, 6/3; 2.5Y 3/2, 4/2, 4/4, 5/2 or 5Y 4/3. Texture is sandy loam or loam. Clay content is 5 to 18 percent. Sodium adsorption ratio is 1 to 8. Most pedons have distinct or prominent redoximorphic features.
The 2Bg horizon has color of 10YR 3/1, 4/1, 5/1; 5Y 3/1, 4/1 or N 3/0. Moist color is 10YR 2/1, 3/1, 4/2; 2.5Y 3/2, 4/2, 5/2, 5/4; 5Y 2/1, 3/1, 3/2, 4/3 or N 2/0. Texture is clay loam or silt loam. Clay content is 20 to 35 percent. Some pedons are calcareous. Sodium adsorption ratio is 2 to 12. Most pedons have distinct or prominent redoximorphic features.
The 2Cg horizon has color of 10YR 5/1, 5/2, 5/3, 6/2, 6/3; 2.5Y 4/2, 6/2; 5Y 5/2, 5/3, 6/2 or 6/3. Moist color is 10YR 3/1, 3/2; 2.5Y 3/2, 4/2, 5/4, 6/2, 6/4; 5Y 4/1, 4/3, 4/4 or 5/3. Texture is clay loam or silt loam. Clay content is 20 to 35 percent. Some pedons are calcareous. Sodium adsorption ratio is 2 to 12. Most pedons have distinct or prominent redoximorphic features. Some pedons have a C horizon that is black clay loam or silt loam and is 0.5 inch thick. Some pedons do not have a C horizon above a depth of 60 inches.
COMPETING SERIES: There are no competing series at this time.
GEOGRAPHIC SETTING: Palazzo soils are in valley basin floors and flood plains. Slope is 0 to 2 percent. These soils formed in mixed alluvium, weathered dominantly from igneous rock. Most of this soil has been leveled, but was hummocky in its natural landscape. Elevation is 90 to 160 feet. The climate is semiarid with hot dry summers and cool moist winters. The mean annual precipitation is 8 to 12 inches. The mean January temperature is 46 degrees F; mean July temperature is 79 degrees F. and the mean annual temperature is 60 to 64 degrees F. The frost-free season is 210 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alros, Bolfar, Dospalos, Elnido, Escano, and Kesterson soils. Alros soils, on valley basin floors, are saline-sodic and have a calcic horizon. Bolfar and Elnido soils, on valley basin floors, have a coarse-loamy particle-size control section. Dospalos soils, on valley basin floors, have a fine particle-size control section. Escano soils, on valley basin floors, have organic matter that decreases regularly and have a calcic horizon. Kesterson soils, on valley basin floors, have a natric horizon and an ochric epipedon.
DRAINAGE AND PERMEABILITY: Poorly drained; negligible runoff; moderately slow permeability. These soils were previously very poorly drained and ponded with stagnant water for extended periods during winter and spring months but are now ponded for periods of 2 to 7 days from December to February in some areas. The water table is now 3.5 to 5 feet from December through February in some areas. They are now artifically drained or have had their water source intercepted. They are partially protected from major flooding by large flood control levees and reservoirs. Some areas are subject to rare flooding in years of abnormally high precipitation.
USE AND VEGETATION: Most of these soils are cultivated and irrigated. Field and vegetable crops are the principal crops. Small acreages are in orchards and pastures.
DISTRIBUTION AND EXTENT: These soils occur near the western edge of the San Joaquin River in the central part of the San Joaquin Valley of California. 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 surveyed as the Columbia series in the Los Banos Area, California 1939 Series Report. These soils are being differentiated by characteristics that show a reducing environment (Aquic Moisture Regime). Additionally they have a fine-loamy texture control section and a mollic epipedon, neither of which are characteristic of Columbia soils.
Series reclassified 5/95. CEC added, and very slow runoff was edited to negligible to comply with new criteria in the Soil Survey Manual.