LOCATION TURLOCK CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Albic Natraqualfs
TYPICAL PEDON: Turlock sandy loam - on a hummocky slope of less than 2 percent, under saltgrass, iodinebush, alkali heath, and other salt tolerant wetland grasses and forbs at 85 feet elevation. (Colors are for dry soil unless otherwise stated. When described on April 26, 1976, the soil was moist throughout).
A--0 to 3 inches; grayish brown (10YR 5/2) sandy loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular and interstitial pores; mildly alkaline (pH 7.8); clear smooth boundary. (1 to 7 inches thick)
E--3 to 4 inches; olive gray (5Y 5/2) loam, dark gray (5Y 4/1) moist; many fine prominent light olive brown (2.5Y 5/6) mottles, common fine distinct olive gray (5Y 5/2) mottles moist; moderate medium subangular blocky structure; very hard, friable, sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular and interstitial pores; mildly alkaline (pH 7.4); abrupt smooth boundary. (1 to 3 inches thick)
Btg--4 to 11 inches; olive gray (5Y 4/2, 5/2) clay loam, very dark gray (5Y 3/1) moist; common medium prominent yellowish brown (10YR 5/8) mottles, common medium prominent dark yellowish brown (10YR 4/4) mottles moist; strong medium columnar structure; extremely hard, friable, sticky and plastic; common very fine roots; many very fine and few fine tubular and interstitial pores; few thin clay films on peds; ESP is 2; mildly alkaline (pH 7.8); clear smooth boundary. (5 to 11 inches thick)
Btgn--11 to 25 inches; olive gray (5Y 5/2) clay loam, dark olive gray (5Y 3/2) moist; common fine prominent black and olive (5Y 2/1, 5/6) mottles, many large prominent black and olive (5Y 2/1, 5/6) mottles moist; moderate medium prismatic and subangular blocky structure; extremely hard, friable, sticky and plastic; common very fine roots; common very fine interstitial pores; common thin clay films on peds; ESP is 15: moderately alkaline (pH 8.2); clear smooth boundary. (6 to 14 inches thick)
Btkn--25 to 36 inches; grayish brown (2.5Y 5/2) clay loam, very dark grayish brown (2.5Y 3/2) moist; few mediumprominent yellow and very dark gray (2.5Y 7/6; N 3/0) mottles, many medium prominent dark gray and olive yellow (N 4/0; 2.5Y 6/6) mottles moist; weak medium subangular blocky structure; very hard, friable, sticky and plastic; few very fine roots; common very fine and fine tubular pores; few thin clay films on peds; strongly effervescent with disseminated lime; moderately alkaline (pH 8.4); clear smooth boundary. (3 to 14 inches thick)
Bkn--36 to 55 inches; pale yellow (2.5Y 7/4) clay loam, olive (5Y 5/4) moist; few fine distinct olive yellow mottles (2.5Y 6/6), many medium prominent olive yellow and pale yellow (5Y 6/6, 7/4) mottles moist; massive; very hard, firm, sticky and plastic; no roots; few very fine tubular pores; violently effervescent with disseminated lime; ESP is 17; strongly alkaline (pH 8.6); clear smooth boundary. (6 to 19 inches thick)
2Ckg--55 to 60 inches; pale yellow (5Y 7/3) silty clay loam, olive (5Y 5/4) moist; many medium prominent yellowish brown (10YR 5/8) mottles, many medium prominent light olive brown and light yellowish brown (2.5Y 5/6, 6/4) mottles moist; massive; hard, firm, sticky and very plastic; few very fine interstitial pores; violently effervescent with disseminated lime; strongly alkaline (pH 8.6).
TYPE LOCATION: Merced County, California; 9 miles north-northwest of the city of Los Banos; 350 feet south of Santa Fe Grade, 1,600 feet northwest of the Triangle Duck Club clubhouse, 2,000 feet east and 800 feet north of the SW corner of section 5, T.9 S., R.10 E. 37 degrees North latitude, 10 minutes, 45 seconds; 120 degrees West longitude, 53 minutes, 45 seconds.
RANGE IN CHARACTERISTICS: Most years the entire profile is saturated from September through April by a water table and stagnant surface water. The depth from the surface to the natric horizon (lower Bt) ranges from 9 to 28 inches. The textural control section averages from 20 to 35 percent clay. Organic matter is 1 to 4 percent in the A horizon. The upper Bt horizon has less than 15 percent exchangeable sodium.
The A horizon has dry color of 10YR 4/2, 5/2, 5/3 or 6/3. Moist colors are 5Y 4/2, 5/1, 5/2; 2.5Y 4/2; 10YR 2/1, 2/2, 3/1, 3/2, 4/3, 4/4 or 5/3. It is sandy loam, fine sandy loam or loam. It is mildly alkaline or moderately alkaline.
The E horizon has dry and moist color of 5Y 4/1, 5/2; 10YR 6/3 or 7/1. Some pedons do not have mottles. It is sandy loam, fine sandy loam or loam. The reaction is neutral to moderately alkaline.
The Bt horizon is 2.5Y 5/2; 5Y 4/2, 5/2, 5/3 or 10YR 5/2. Moist colors are 2.5Y 3/2, 4/2, 4/4; 5Y 3/1, 3/2, 4/3, 5/2; 10YR 3/1, 3/2, 4/2, 4/4 or 5/3. It is clay loam or loam. Some pedons are storngly effervescent throughout. It is mildly alkaline to strongly alkaline. EC ranges from 5 to 35 mmhos/cm and the ESP rnages from 15 to 35, except the upper Bt which is less than 15.
The Bkn horizon is 5Y 7/3; 2.5Y 5/2, 5/4, 6/4, 7/4; or 10YR 8/2. Moist colors are 5Y 5/4; 2.5Y 4/2, 5/4 or 6/4. It is sandy clay loam, silty clay loam or clay loam. The calcium carbonate equivalent ranges from 2 to 15 percent. Reaction is moderately alkaline or strongly alkaline. ESP ranges from 15 to 25.
The 2Ckg horizon is loam, clay loam, or silty clay loam. Reaction is moderately alkaline or strongly alkaline. It is firm or very firm when moist. Some pedons have durinodes that are 10 to 15 mm in size and occupy up to 5 percent of the soil mass. This horizon is stratified in some pedons.
COMPETING SERIES: These are the Edminster, Kesterson, Lindsey, Santanela, Volta (T) and Waukena series in other families. Edminster and Kesterson soils have tonguing of albic materials and more than 15 percent exchangeable sodium in the upper part of the natric horizon and are poorly drained. In addition, Kesterson soils have a calcic horizon. Lindsey soils are fine and are somewhat poorly drained. Santanela soils have more than 15 percent exchangeable sodium in the upper part of the natric horizon. Volta soils have a duripan of 45 to 55 inches. Waukena soils have more than 15 percent exchangeable sodium in the upper natric horizon and have xeric moisture regimes.
GEOGRAPHIC SETTING: Turlock soils are in the valley basin rim and low alluvial fans. They have developed from mixed alluvium derived from granitic rocks. Slopes are 0 to 2 percent. Most of the soil areas are hummocky or channeled except where land leveled. Elevations are 70 to 110 feet. The climate is semiarid with hot dry summers and cool moist winters. The mean annual precipitation is about 11 inches. Mean January temperature is 46 degrees F; mean July temperature is 79 degrees F. The mean annual temperature is about 62 degrees F. The frost-free season is 210 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Edminster, Kesterson, Santanela soils, and the Triangle soils. Triangle soils have intersecting slickensides and develop wide cracks upon drying.
DRAINAGE AND PERMEABILITY: Very poorly drained; ponded; very slow permeability.
USE AND VEGETATION: These soils are ponded from September to April and used for waterfowl habitat with some of the areas used for limited livestock grazing during the spring and summer between hunting seasons. The vegetation is saltgrass, iodinebush, alkali heath, and other salt tolerant grasses and forbs.
DISTRIBUTION AND EXTENT: These soils are distributed along the basin rim of the central part of the San Joaquin Valley in California. They are moderately extensive in 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 Waukena series in the Los Banos Area, series 1939 report. They are being differentiated by characteristics that show a reducing environment (Aquic Moisture Regime) and lacking more than 15 percent exchangeable sodium in the upper part of the natric horizon, that is not characteristic of the Waukena series.
ADDITIONAL DATA: NSSL pedon S79CA-047-002 (type location)
Field measurements of ESP determined by versinate method. pH determined by colorimetric method using Thymol Blue and Hellige-Truog Triplex indicators. Texture determined by modified Bouyoucos method.