LOCATION MARVIN CAEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Aquic Haploxeralfs
TYPICAL PEDON: Marvin silty clay loam - grain. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 8 inches; grayish brown (2.5Y 5/2) silty clay loam, very dark grayish brown (2.5Y 3/2) moist; few faint yellowish brown (10YR 5/6) mottles; massive; hard, friable, slightly sticky, plastic; many fine roots; many very fine pores; slightly acid; abrupt smooth boundary. (5 to 10 inches thick)
A3--8 to 13 inches; grayish brown (2.5Y 5/2) silty clay loam, very dark grayish brown (2.5Y 3/2) moist; few faint yellowish brown (10YR 5/6) mottles; moderate medium and coarse subangular blocky structure; hard, friable, slightly sticky, plastic; many fine roots; many very fine pores; few fine iron manganese pellets; slightly acid; clear smooth boundary. (3 to 8 inches thick)
B1--13 to 17 inches; grayish brown (2.5Y 5/2) heavy silty clay loam, very dark grayish brown (2.5Y 3/2) moist; moderate medium and coarse subangular blocky structure; very hard, firm, sticky, plastic; common very fine roots; many very fine pores; thin discontinuous clay films in some pores; few small iron-manganese pellets; mildly alkaline; clear smooth boundary. (3 to 10 inches thick)
B2t--17 to 29 inches; dark grayish brown (2.5Y 4/2) silty clay, very dark grayish brown (2.5Y 3/2) moist; moderate medium and coarse subangular blocky structure; very hard, firm, sticky, plastic; common fine roots in upper part, few below; many very fine pores; many thin continuous clay films in pores; few small iron-manganese pellets; mildly alkaline; clear smooth boundary. (6 to 25 inches thick)
B3--29 to 42 inches; light olive brown (2.5Y 5/3) silty clay, dark grayish brown (2.5Y 4/2) moist; moderate medium and coarse subangular blocky structure; very hard, firm, sticky, plastic; few very fine roots; many very fine pores; thin continuous clay films in pores; slightly calcareous; lime segregated in small, soft concretions; mildly alkaline, gradual smooth boundary. (10 to 20 inches thick)
C--42 to 60 inches; light olive brown (2.5Y 5/3) silty clay loam, dark brown (10YR 4/3) moist; massive; hard, friable, sticky, plastic; few roots; many very fine pores; few thin clay films in pores; slightly effervescent, lime in small soft concretions and disseminated; moderately alkaline.
TYPE LOCATION: Glenn County, California; 1 1/2 miles SE of Butte City, 75 feet east of the SW corner of sec. 34, T.19N., R.1W.
RANGE IN CHARACTERISTICS: The solum thickness ranges from 27 to 66 inches. The mean annual soil temperature is about 62 degrees F. The soil above 20 inches depth is continuously dry in most years from about May 20 to October 15. The soils are temporarily saturated in the upper part due to winter rains, or irrigation and slow subsoil permeability. The exchangeable sodium is less than 15 percent. The A horizon is light brownish gray, grayish brown, or dark grayish brown dry and very dark grayish brown when moist. Hue is 10YR or 2.5Y. The A horizon is mottled. It contains about 2 to 3 percent organic matter. It ranges from silty clay loam to silty clay, and from medium acid (pH 6.0) to mildly alkaline. The soil has an A3 horizon or B1 horizon or both or the boundary between the A horizon and B2 horizon is gradual. The B2t horizon ranges from grayish brown to dark grayish brown dry and is dark grayish brown when moist. Hue is 10YR or 2.5Y. Some pedons have mottles in the B2 horizon. It is silty clay or clay; and mildly to moderately alkaline. The B3 horizon is light olive brown, pale brown, or grayish brown dry and dark grayish brown moist. Hue is 10YR or 2.5Y. It is mildly to moderately alkaline and slightly to strongly calcareous. The C horizon is similar to the B3 horizon in color and reaction. Some areas are affected by salts.
COMPETING SERIES: These are the Artois, Lethent, Plaza, Rincon, and Zamora series. Artois soils have moist color value of 4 or more in the A horizons and yellowish brown Bt horizons. Lethent soils have natric horizons. Plaza soils have mottled clay loam Bt horizons. Rincon soils lack mottles of 2 or lower chroma in all parts. Zamora soils lack mottles, and have silty clay loam Bt horizons.
GEOGRAPHIC SETTING: Marvin soils are on nearly level flood plains at elevations of 10 to 100 feet under annual grasses and forbs. They formed in fine textured alluvium from mixed sources. The climate is dry subhumid mesothermal. Summer is hot and dry and winter is moist and cool. Mean annual precipitation is 15 to 25 inches. Mean annual temperature is about 60 to 62 degrees F., average January temperature is about 45 degrees F., and average July temperature about 78 degrees F. The frost-free season is 250 to 330 days.
GEOGRAPHICALLY ASSOCIATED SOILS: The Capay, Rincon, Sycamore, Willows and Zamora soils are in the same general area. Capay and Willows soils have slickensides. Sycamore soils have less than 35 percent clay in the series control section.
DRAINAGE AND PERMEABILITY: Moderately well to somewhat poorly drained; runoff is slow and permeability is slow.
USE AND VEGETATION: Irrigated and dry cropland and pasture. Main crops are grain, field crops, sugar beets, alfalfa and rice. Natural vegetation is annual grasses and forbs, and open stands of valley oaks . Saline-alkali tolerant plants are in alkali areas.
DISTRIBUTION AND EXTENT: Central Sacramento Valley, California. The soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Oroville Area, California, 1926.
REMARKS: Marvin soils were formerly classified as Noncalcic Brown soils.
OSED scanned by SSQA. Last revised by state on 1/70.