LOCATION GAZWELL                 CA

Established Series
Rev: WRR/AJT/WBS/DJE/ET
05/2016

GAZWELL SERIES


The Gazwell series consists of very deep, very poorly drained mineral soils with a buried organic soil. They formed in alluvium from mixed rock sources underlain by decomposed hydrophytic plant remains. They are in backswamps along the edge of fresh water marshes. Slopes are 0 to 2 percent. The mean annual precipitation is about 38 centimeters (15 inches) and the mean annual temperature is about 16 degrees C (61 degrees F).
TAXONOMIC CLASS: Fine, mixed, superactive, thermic Cumulic Endoaquolls

TYPICAL PEDON: Gazwell mucky clay--on a slope of less than 1 percent in a cultivated field at an elevation of 4.5 meters (15 feet) below sea level. (Colors are for dry soil unless otherwise stated. When described the soil was moist below 7.5 centimeters (3 inches)).

Ap1--0 to 20 centimeters (0 to 8 inches); dark grayish brown (10YR 4/2) mucky clay, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many fine interstitial pores; 15 percent organic matter; moderately acid (pH 6.0); clear smooth boundary. (5 to 50 centimeters (2 to 20 inches) thick)

Ap2--20 to 43 centimeters (8 to 17 inches); dark grayish brown (10YR 4/2) mucky clay, very dark brown (10YR 2/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine interstitial pores; 14 percent organic matter; moderately acid (pH 6.0); gradual smooth boundary. (23 to 43 centimeters (9 to 17 inches) thick)

Ap3--43 to 76 centimeters (17 to 30 inches); dark grayish brown (10YR 4/2) mucky clay, very dark brown (10YR 2/2) moist; massive, slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine interstitial pores; common, fine reddish brown (5YR 4/4) moist fragments of burnt material mixed throughout; 13 percent organic matter; moderately acid (pH 6.0); abrupt wavy boundary. (18 to 33 centimeters (7 to 13 inches) thick)

2Ab--76 to 91 centimeters (30 to 36 inches); very dark gray (10YR 3/1) mucky clay, black (10YR 2/1) moist; few medium distinct yellowish red (5YR 4/6) redox concentrations, dark reddish brown (5YR 3/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine roots; many very fine interstitial pores; discontinuous dark yellowish brown (10YR 4/4) moist 0.5 inch thick bands of burnt material; 25 percent organic matter; moderately acid (pH 5.8); abrupt smooth boundary. (10 to 18 centimeters (4 to 7 inches) thick)

3Oa1--91 to 122 centimeters (36 to 48 inches); very dark gray (10YR 3/1) broken face sapric material, black (10YR 2/1) moist; common fine distinct strong brown (7.5YR 4/6) redox concentrations, red (2.5YR 4/8) moist; no visible fibers; massive; slightly hard, very friable, nonsticky and nonplastic; 65 percent mineral material; very strongly acid (pH 5.0 in water); abrupt wavy boundary. (13 to 41 centimeters (5 to 16 inches) thick)

3Oa2--122 to 155 centimeters (48 to 61 inches); very dark gray (10YR 3/1) broken face sapric material, black (10YR 2/1) moist; about 40 percent fibers, less than 5 percent rubbed; strong very fine platy structure; slightly hard, firm, nonsticky and nonplastic; dark brown (10YR 3/3) fibers, dark yellowish brown (10YR 3/4) moist; 67 percent mineral material; moderately acid (pH 6.0 in water). (25 to 38 centimeters (10 to 15 inches) thick)

TYPE LOCATION: Sacramento County, California; about 2.3 miles southeast of Rio Vista on Brannan Island, 2,150 feet northeast from Tomato Slough on dirt road on north side of major drain and 200 feet north into field in an unsectionized area; West Longitude 121 degrees 39 minutes 40 seconds North Latitude 38 degrees 07 minutes 50 seconds.

RANGE IN CHARACTERISTICS:
The mean annual soil temperature: 17 to 18 degrees C (62 to 65 degrees F) and remains above 8 degrees C (47 degrees F) throughout the year.
Soil moisture: the soil between the depths of 13 and 38 centimeters (5 and 15 inches) was saturated before it was artificially drained
Depth to the buried organic horizons: 71 to 99 centimeters (28 to 39 inches)
Clay content: 40 to 60 percent average
Organic matter: 10 to 20 percent average

Ap horizon:
Hue: 10YR dry and moist
Value: 3, 4 or 5 dry, 2 or 3 moist
Chroma: 1 or 2 dry and moist
Organic matter: 7 to 15 percent
Texture of the fine earth: mucky clay or mucky silty clay
Reaction: strongly to slightly acid

Ab horizon:
Hue: 10YR dry and moist
Value: 3, 4 or 5 dry and 2 or 3 moist
Chroma: 1 dry and moist
Organic matter: 10 to 27 percent
Texture of the fine earth: mucky clay or mucky silty clay
Reaction: slightly acid to strongly acid
Other features: Some pedons have a burned layer that is 0.5 to 2 inches in thickness within the Ab or Oa1 horizons at a depth of 51 to 114 centimeters (20 to 45) inches. Moist color is 10YR 5/6, 4/4; 7.5YR 4/6, 4/3; 5YR 5/6, 5/4 or 2.5YR 4/8.

The Oa horizon:
Hue: 10YR or N dry and moist
Value: 2, 3, 4, or 5 dry and 2 moist
Chroma: 1 or 2 dry and moist
Organic matter: 27 to 40 percent, fiber content ranges from less than 5 percent in the upper part to about 70 percent in the lower part before rubbing and 0 percent after rubbing
Texture of the fine earth: clay, silty clay, sandy clay or silty clay loam
Structure: Weak to strong
Reaction: very strongly to moderately acid

COMPETING SERIES: These are the Egbert and Peltier soils. Both the Egbert and Peltier soils do not have a buried Histosol.

GEOGRAPHIC SETTING: Gazwell soils are in backswamps along the edge of fresh water marshes. Slopes are 0 to 2 percent. They formed in alluvium derived from mixed rock sources underlain by decomposed hydrophytic plant remains. The plant remains consist of reeds and tules. Elevations are 4.5 meters (15 feet) below sea level to sea level. The climate is dry subhumid with hot dry summers and cool moist winters. Mean annual precipitation is 33 to 43 centimeters (13 to 17 inches). Average January temperature is 8 degrees C (46 degrees F), average July temperature is 24 degrees C (75 degrees F) and the average annual temperature is 16 degrees C (61 degrees F). Frost-free season is 275 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Rindge, Sailboat, and Scribner soils. Rindge soils have continuous sapric organic material to a depth of 130 centimeters (51 inches) or more and are in sloughs and drainage channels. Sailboat and Scribner soils have a fine-loamy textural control section. Sailboat soils are on natural levees. Scribner soils are on edges of backswamps.

DRAINAGE AND PERMEABILITY: Natural drainage is very poor. These soils are artificially drained, runoff is very slow, permeability is moderate in the mineral soil and rapid in the underlying organic soil. The water table is maintained by pumping at a depth of 46 to 152 centimeters (18 to 60 inches). Depth to water table is 46 to 91 centimeters (18 to 36) inches in winter and early spring months. These soils subside. These soils are protected by levees and have a rare hazard of flooding.

USE AND VEGETATION: Soils are cultivated. Corn and wheat are the principle crops.

DISTRIBUTION AND EXTENT: Sacramento-San Joaquin Delta area. The soils are moderately extensive.

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

SERIES ESTABLISHED: Sacramento County, 1985. Name is coined.

REMARKS: The activity class was added to the classification in February of 2003. Competing series were checked in 2016. - ET

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon: 0 to 91 centimeters (0 to 36 inches) (Ap1, Ap2, Ap3, 2Ab horizons)

Buried Histosol: 91 to 152 centimeters (36 to 60 inches) (3Oa1, 3Oa2 horizons)

Aquoll feature; artificially drained; has distinct redox concentrations in lower part of mollic epipedon.

Organic matter by induction furnace (UCD), clay content by hydrometer after organic matter oxidized with hydrogen peroxide.

ADDITIONAL DATA: This soil was laboratory sampled as 81P03130094 (S1979CA067022) and 15N0730 (S2015CA067001)


National Cooperative Soil Survey
U.S.A.