LOCATION ORITA                   CA

Established Series
Rev. NEE/LCL/ET
12/2015

ORITA SERIES

The Orita series consist of very deep, well drained soils that formed in alluvium from mixed sources. Orita soils are on fan remnants and terraces. Slopes are 0 to 2 percent. The mean annual precipitation is about 4 inches and the mean annual air temperature is about 72 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, hyperthermic Typic Haplargids

TYPICAL PEDON: Orita gravelly fine sandy loam - desert. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with a continuous pavement of fine gravel of leuco-granite and some schist and quartz; some gravel are weakly varnished by dark coatings, some by calcium carbonate.

C1--0 to 4 inches; light brown (7.5YR 6/4) gravelly fine sandy loam, brown (7.5YR 4/4) moist; moderate and strong thick platy structure; soft, very friable; few fine roots; many very fine vesicular pores; about 15 percent gravel; slightly effervescent, lime disseminated; moderately alkaline (pH 8.2); clear smooth boundary. (3 to 12 inches thick)

C2--4 to 10 inches; light brown (7.5YR 6/4) gravelly sand, brown (7.5YR 5/4) moist; weak and moderate thick platy structure; soft, loose; few fine roots; many very fine pores; about 25 percent gravel; slightly effervescent, lime disseminated; moderately alkaline (pH 8.2); abrupt smooth boundary. (0 to 6 inches thick)

2A--10 to 22 inches; brown (7.5YR 5/4) fine sandy loam, dark brown (7.5YR 4/4) moist; massive; slightly hard, very friable, slightly sticky; few fine roots to 18 inches; many very fine tubular pores; strongly effervescent, fine lime mycelia; moderately alkaline (pH 8.2); gradual smooth boundary. (10 to 15 inches thick)

2Bt--22 to 42 inches; reddish yellow (5YR 6/6) gravelly clay loam, yellowish red (5YR 4/6) moist; massive; hard, friable, sticky, plastic; many very fine and fine tubular pores; about 15 percent gravel; thin clay films line a few pores; strongly and violently effervescent; fine and medium soft bodies of lime; moderately alkaline (pH 8.2); gradual irregular boundary. (10 to 20 inches thick)

2Btk1--42 to 60 inches; light reddish brown (5YR 6/4) gravelly clay loam, reddish brown (5YR 4/4) moist; massive; hard, friable, sticky, plastic; many very fine and fine tubular pores; 20 percent gravel; clay bridges between mineral grains; common stains on mineral grains; strongly and violently effervescent; lime segregated into medium and large soft bodies and concretions; moderately alkaline (pH 8.2); gradual irregular boundary. (6 to 10 inches thick)

2Btk2--60 to 68 inches; reddish yellow (5YR 7/6) gravelly clay loam, yellowish red (5YR 4/6) moist; massive; slightly hard, very friable, sticky, slightly plastic; many very fine and fine tubular pores; about 25 percent gravel; clay bridges and coatings on mineral grains; strongly and violently effervescent; lime in fine concretions and soft bodies; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 10 inches thick)

2C--68 to 80 inches; light brown (7.5YR 6/4) gravelly fine sandy loam, brown (7.5YR 5/4) moist; massive; soft, very friable; many fine and very fine pores; about 40 percent gravel; few dark coats on mineral grains; strongly effervescent in matrix, violently effervescent on carbonate coated gravel; moderately alkaline (pH 8.2).

TYPE LOCATION: Riverside County, California; about 7 miles west and 5 miles north of Blythe, about 55 feet west and 5 feet north of brass capped monument at SE corner of sec. 36, T. 5 S., R. 21 E. 114 degrees, 43 minutes, 41 seconds west longitude, 33 degrees, 41 minutes, 24 seconds north latitude; UTM zone 11 710567e and 3730099n NAD83.

RANGE IN CHARACTERISTICS: These soils have an overwash from one or two to 19 inches thick. Solum thickness ranges from 26 to 60 inches. The soil is somewhat stratified and calcareous throughout. Most horizons are gravelly, but within the solum gravel ranges from none to about 55 percent by volume. The mean annual soil temperature is about 75 degrees F., and the soil is usually dry. An open to continuous but not closely fitted gravel pavement is at the surface. The gravels have little to no desert varnish, but some have carbonate coatings.

The overwash and 2A horizon are similar. They have hue of 10YR or 7.5YR, value of 5 through 7 dry and 4 or 5 moist, and chroma of 3 through 6 moist. The overwash ranges from loamy sand to fine sandy loam, and the 2A horizon is fine sandy loam or sandy loam. The surface horizon commonly has platy structure except that those of loamy sand may be single grained. The lower part of the overwash and the 2A horizon may be massive.

The 2Bt horizon has 10YR through 5YR hue and tends to be redder than the overlying horizons. It ranges from heavy fine sandy loam to clay loam, and contain between 18 and 30 percent clay. Reaction is moderately or strongly alkaline. All parts of the 2Bt horizon may contain some bodies and concretions of lime but they are greater in number and larger in the lower part, which commonly contains nodules and weak cementation.

The 2C horizon has hue of 7.5YR or 10YR, and value and chroma similar to the overlying horizons. It ranges from sand to fine sandy loam. Some gravels have carbonate coatings. Reaction is slightly or moderately alkaline.

COMPETING SERIES: Similar and related soils are in the Aco, Adelanto, Chuckawalla, Cornville, Dona Ana, and Mohave series. Aco soils lack argillic horizons and contain less than 18 percent clay. Adelanto soils have less than 18 percent clay in the argillic horizon. Chuckawalla soils are very gravelly or very cobbly in the lower part of the B2t horizon. Cornville, Dona Ana and Mohave soils have mean annual soil temperature of less than 72 degrees F.

GEOGRAPHIC SETTING: The Orita soils are on fan remnants and terraces at elevations of 300 to 1,600 feet. Slopes are 0 to 2 percent. The soils formed in somewhat stratified and gravelly alluvium derived from many kinds of rock. The climate is arid. Mean annual precipitation is about 3 to 5 inches. The average January temperature is about 53 degrees F., the average July temperature is about 90 degrees F., and the average annual temperature is 70 to, 73 degrees F. The frost-free season is about 270 to 360 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Aco and Chuckawalla soils and the Carrizo and Rositas soils. The Carrizo and Rositas soils lack argillic horizons.

DRAINAGE AND PERMEABILITY: The Orita soils are well drained. Runoff is very low to medium. Permeability is moderate.

USE AND VEGETATION: Orita soils have very little value as rangeland. They are well suited for cultivation where water is available for irrigation. Native vegetation is a sparse cover mainly of creosote bush and white bursage.

DISTRIBUTION AND EXTENT: Southern California and probably southwestern Arizona. They are moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES ESTABLISHED: Imperial County, California, 1944.

REMARKS: The Orita soils were formerly classified as Red Desert soils.

OSED scanned by SSQA. Last revised by state on 12/68.

Series reclassified on September, 1994. Competing series not reviewed at that time. UTM added 3/2009 ET. Responsibility for this series was transferred from Davis to Phoenix 12/2015.

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National Cooperative Soil Survey
U.S.A.