LOCATION CHECKER CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, thermic Calcic Aquisalids
TYPICAL PEDON: Checker loam - on a nearly level mound of 1 percent, under saltgrass, Spanish brome, annual barley and other grasses and forbs and at an elevation of 100 feet. (Colors are for dry soil unless otherwise stated. When described on September 5, l979, the soil was dry to 15 inches and moist below.)
A--0 to 4 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; few very fine and fine tubular pores; EC is 92 mmhos/cm; ESP is 56; moderately alkaline (pH 8.0); clear smooth boundary. (3 to 6 inches thick)
Bwnz--4 to 9 inches; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; strong medium subangular blocky structure; slightly hard, very friable, sticky and plastic; few very fine, fine and medium roots; common very fine tubular pores; strongly effervescent with disseminated lime; 18 percent calcium carbonate equivalent; EC is 30 mmhos/cm; ESP is 40; moderately alkalilne (pH 8.0); clear smooth boundary. (4 to 7 inches thick)
Bknz--9 to 15 inches; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; massive; slightly hard, very friable, slightly sticky and plastic; few very fine, fine and medium roots; common very fine tubular pores; slightly effervescent with disseminated lime and segregated as few fine irregular soft masses; 18 percent calcium carbonate equivalent; EC is 22 mmhos/cm; ESP is 32; moderately alkaline (pH 8.0); clear wavy boundary. (7 to 10 inches thick)
Bnz--15 to 36 inches; light gray (10YR 7/2) loam, brown (10YR 5/3) moist; massive; slightly hard, very friable, sticky and plastic; few fine and medium roots; common very fine and few fine tubular pores; strongly effervescent with disseminated lime; 12 percent calcium carbonate equivalent; EC is 32 mmhos/cm; ESP is 40; moderately alkaline (pH 8.0); clear wavy boundary. (18 to 24 inches thick)
C--36 to 55 inches; light gray (5Y 7/2) clay loam, olive (5Y 5/3) moist; massive; hard, friable, sticky and plastic; few very fine and fine roots; common very fine tubular pores; strongly effervescent with disseminated lime and segregated as few fine irregular soft masses; 10 percent calcium carbonate equivalent; EC is 22 mmhos/cm; ESP is 31; moderately alkaline (pH 8.0); clear wavy boundary. (18 to 24 inches thick)
2Ck--55 to 59 inches; light gray (5Y 7/2) clay loam, olive (5Y 5/3) moist; few fine prominent reddish yellow (7.5YR 6/6) mottles, strong brown (7.5YR 5/6) moist; massive; slightly hard, very friable, sticky and very plastic; no roots; common fine and few medium tubular pores; violently effervescent with disseminated lime and segregated as many medium irregular soft masses and concretions; 34 percent calcium carbonate equivalent; EC is 14 mmhos/cm; ESP is 20; strongly alkaline (pH 8.4); abrupt wavy boundary. (2 to 9 inches thick)
2C--59 to 61 inches; pale yellow (5Y 8/3) silty clay, pale olive (5Y 6/3) moist; few fine prominent reddish yellow (7.5YR 6/6) mottles, strong brown (7.5YR 5/6) moist; massive; slightly hard, very friable, very sticky and very plastic; few very fine tubular pores; slightly effervescent with disseminated lime; 10 percent calcium carbonate equivalent; EC is 14 mmhos/cm; ESP is 28; strongly alkaline (pH 8.5).
TYPE LOCATION: Merced County, California; about 5.5 miles southeast of the city of Los Banos, 2,800 feet east and 550 feet north of the SW corner of section 27, T.10 S., R.11 E., Los Banos Quadrangle.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 60 degrees to 62 degrees F. The soil is warmer than 47 degrees F from January 20 to December 1. The soil between 16 and 48 inches is moist in all parts down to the capillary water table moisture from January 1 to May 1 and dry in all parts above the water table capillary fringe from July 1 to November 1. The water table fluctuates between 36 and 48 inches of the surface in October through March. Calcium carbonate equivalent ranges from 5 to 40 percent. The EC ranges from 10 to 100 mmhos/cm, and the ESP ranges from 15 to 60. The organic matter in the A horizon is less than 1 percent.
The A horizon is 10YR 4/2, 5/1, 5/2, 5/3, 6/2, 6/3; 2.5Y 5/2, 6/2, 6/6 or 7/4. Moist colors are 10YR 3/1, 3/2, 3/3, 4/2, 4/3, 5/3; 2.5Y 3/2, 4/2, 4/4 or 6/4. The clay content ranges from 18 to 27 percent. Disseminated lime ranges from none to violently effervescent and is always effervescent in the lower part.
The C horizon is 10YR 6/3, 6/4, 7/2, 7/3, 7/6; 2.5Y 5/4, 6/6, 7/2, 7/4, 7/6; 5Y 6/3, 6/4, 7/2, 7/3 or 8/2, 8/3. Moist colors are 10YR 4/3, 5/3, 5/6, 6/2; 2.5Y 4/2, 4/4, 5/2, 5/4, 6/2, 6/4; 5Y 4/2, 4/3, 5/3, 6/2 and 6/3. Mottles are few fine prominent 7.5YR 4/6, 5/6, or 6/6; 10YR 5/6, 8/1; 2.5Y 5/6, 6/6; 5GY 5/1, 6/1, 7/1; 5G 4/1, 4/4 or 5/1 moist. It is loam or clay loam with 20 to 30 percent clay in the upper part. The lower part is clay loam or silty clay with 35 to 45 percent clay. In some pedons the lower part of the C horizon is loamy sand or clay. Disseminated lime ranges from slightly to violently effervescent, and the reaction is moderately alkaline to strongly alkaline.
COMPETING SERIES:
GEOGRAPHIC SETTING: Checker soils are on mounds in the valley basin and have slopes of 0 to 2 percent. Elevations range from 100 to 110 feet. These soils are formed in mixed alluvium dominantly from sedimentary rock. The climate is semiarid with hot dry summers and cool moist winters. The mean annual precipitation is 9 to 12 inches. The mean January temperature is 46 degrees F; mean July temperature is 79 degrees F and the mean annual temperature is 62 degrees F. The frost-free season is 210 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Agnal, Britto and Triangle soils. Agnal, Britto and Triangle soils are very poorly drained and have fine textures.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained, slow runoff, moderately slow permeability. The water table fluctuates between 36 and 48 inches of the surface in October through March.
USE AND VEGETATION: These soils being on mounds are used as waterfowl hunting access areas and as rangeland. The range vegetation includes saltgrass, Spanish brome, annual barley, alkali heath, pickleweed, iodine bush and other grasses and forbs.
DISTRIBUTION AND EXTENT: These soils occur on mounds in the valley basin of the Central San Joaquin Valley. They are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Merced County, California 1984. Name is coined.
REMARKS:
Diagnostic horizons and other features recognized in this pedon:
Salic horizon -- the zone from 15 to 36 inches (the Bnz horizon)
Calcic horizon -- the zone from 9 to 15 inches (the Bknz horizon)
These soils were mapped as Piper in the Los Banos Area, Series 1939 report. They are being differentiated by having a Xeric moisture regime and being fine-loamy. pH determined by colormetric method using Thymol Blue and Hellige-Troug Triplex indicators. Texture determined by hydrometer method. Soluble salts and exchangeable sodium determined by saturation extract. Organic matter determined by Walkley-Black digestion method. Calcium carbonate equivalent determined by HC1, syringe field kit. Presence of lime determined by 10 percent HC1.
Series reclassified 7/98, competing series not completed.