LOCATION RICECROSS CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Pachic Ultic Argixerolls
TYPICAL PEDON: Ricecross loam - on a south facing slope of 1 percent under valley oaks and annual grasses and forbs at 1675 feet elevation. (Colors are for dry soil unless otherwise stated. When described on August 29, l985, the soil was dry to 11 inches and slightly moist below.)
A--0 to 6 inches; brown (7.5YR 5/4) loam, dark brown (7.5YR 3/2) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine roots; few very fine and fine tubular and common very fine interstitial pores; 5 percent pebbles; slightly acid (pH 6.1); clear smooth boundary. (5 to 8 inches thick)
Bt1--6 to 11 inches; brown (7.5YR 4/4) loam, dark reddish brown (5YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine roots; common fine tubular and few very fine and fine interstitial pores; common thin clay films on ped faces and lining pores; 5 percent pebbles; slightly acid (pH 6.5); clear smooth boundary. (4 to 7 inches thick)
Bt2--11 to 19 inches; brown (7.5YR 4/4) loam, dark reddish brown (5YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine roots; few very fine and fine interstitial and common fine tubular pores; 5 percent pebbles; neutral (pH 7.0); gradual smooth boundary. (6 to 10 inches thick)
Bt3--19 to 33 inches; brown (7.5YR 4/4) clay loam, dark reddish brown (5YR 3/3) moist; moderate medium subangular blocky structure; hard, friable, sticky and plastic; few very fine and coarse roots; common very fine tubular pores; many thin clay films lining pores and on ped faces; 5 percent pebbles; neutral (pH 7.0) clear smooth boundary. (10 to 20 inches thick)
Bt4--33 to 50 inches; brown (7.5YR 4/4) clay loam, dark reddish brown (5YR 3/3) moist; moderate medium subangular blocky structure; hard, friable, sticky and plastic; few very fine and fine roots; common very fine and fine tubular pores; many thin clay films lining pores and on ped faces and few moderately thick clay films on ped faces; 5 percent pebbles; neutral (pH 7.0) clear smooth boundary. (15 to 25 inches thick)
Bt5--50 to 72 inches; brown (7.5YR 5/4) clay loam, mixed reddish brown (5YR 4/4) and dark reddish brown (5YR 3/4) moist; common fine black (10YR 2/1) stains; moderate medium subangular blocky structure; hard, friable, sticky and plastic; few very fine and fine roots; common very fine tubular pores; many thin clay films lining pores and on ped faces; 5 percent pebbles; neutral (pH 7.0).
TYPE LOCATION: Yuba County, California; about 3.25 miles south of Oregon House, California, on Rice Crossing Road, then 600 feet southwest on dirt road; about 1650 feet south and 1750 feet west of the northeast corner section 24 T. 17N., R. 6E. MDBM, French Corral Quadrangle.
RANGE IN CHARACTERISTICS: Solum is 30 to 60 or more inches. The mean annual soil temperature is 58 to 61 degrees F. The soil temperature is below 47 degrees F. from Jan. 15 to Feb. 15. The soil moisture control section is dry in all parts from June 1 to October 31 and is moist in all parts from November 15 to May 15. Rock fragments range from 0 to 15 percent. Organic matter content is 1 to 3 percent in the upper 36 inches. Base saturation in the upper 30 inches is 60 to 75 percent.
The A horizon has dry color of 10YR 5/3, 5/2, 4/3, 4/2, 7.5YR 5/4, 4/4 or 3/4 and moist color of 10YR 3/3, 3/2, 2/2 or 7.5YR 3/2. Clay content ranges from 15 to 25 percent.
The Bt horizon has dry color of 10YR 5/3, 7.5YR 5/6, 5/4, 4/4 or 5YR 5/3 and moist color of 10YR 3/3, 7.5YR 4/4, 3/4, 5YR 4/4, 3/4 or 3/3. Values and chromas of more than 3 are below 30 inches. It is loam or clay loam with 20 to 30 percent clay. Reaction is slightly acid to neutral.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Ricecross soils are on stream terraces. Slopes range from 0 to 2 percent. The soils formed in alluvium from mixed sources. Elevation is 125 to 1900 feet. The climate has hot dry summers and cool moist winters. The average annual precipitation is 22 to 50 inches. The average January temperature is 46 degrees F.; the average July temperature is 79 degrees F.; mean annual temperature is 58 to 62 degrees. The frost-free season is 235 to 270 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Flanly, Orose, Sobrante and Verjeles soils. Flanly, Sobrante and Verjeles soils are 20 to 40 inches to bedrock. Orose soils are 10 to 20 inches to bedrock. They are all on higher sideslopes above Ricecross soils.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately slow permeability. Subject to rare or occasional flooding.
USE AND VEGETATION: Used mainly for livestock grazing, wildlife habitat, watershed and homesites. Natural vegetation is annual grasses and forbs and scattered Valley Oak.
DISTRIBUTION AND EXTENT: Foothills of the Sierra Nevada Range in California. The series is not extensive. MLRA is 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Yuba County, California, l992S.
REMARKS:
Ricecross soils were mapped as Chualar soils in the "Soils of the Yuba Area", University of California, Davis and Yuba County, l969.
The activity class was added to the classification in February of 2003. Competing series were not checked at that time. - ET
Diagnostic horizon and features recognized in this pedon include:
Mollic epipedon--the zone from the soil surface to about 33 inches (A, Bt1, Bt2, and Bt3 horizon).
Argillic horizon--the zone from about 6 to 72 inches (Bt1, Bt2, Bt3, Bt4, and Bt5 horizon)
Ultic intergrade - base saturation 50 to 75 percent in the argillic horizon.