LOCATION TAJEA CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Typic Argixerolls
TYPICAL PEDON: Tajea loam on a north facing slope of 45 percent under a 25 percent canopy of oak with an understory of annual grasses and forbs at 2,280 feet elevation. Colors are for dry soil unless otherwise stated. When described November 5, 1985, the soil was slightly moist below 10 inches.
A1--0 to 2 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate fine granular structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine irregular interstitial and common very fine tubular pores; neutral (pH 6.6); clear wavy boundary. (2 to 12 inches thick)
A2--2 to 10 inches; pale brown (10YR 6/3) loam, dark brown (10YR 3/3) moist; weak coarse angular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine, fine, medium and coarse roots; many very fine interstitial and common very fine tubular pores; neutral (pH 7.0); gradual wavy boundary. (0 to 8 inches thick)
Bt1--10 to 20 inches; light yellowish brown (10YR 6/4) clay loam, brown (10YR 4/3) moist; weak course subangular blocky structure; hard, friable, sticky and plastic; common very fine and fine roots; many very fine interstitial and few very fine tubular pores; many thin clay films on ped faces and bridging mineral grains; slightly alkaline (pH 7.5); gradual wavy boundary. (12 to 20 inches thick)
Bt2--20 to 27 inches; light yellowish brown (10YR 6/4) gravelly clay loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; hard, friable, sticky and plastic; few very fine and common coarse roots; common very fine interstitial and few very fine tubular pores; many thin clay films on ped faces and bridging mineral grains; 25 percent gravel by volume; slightly alkaline (pH 7.5); gradual wavy boundary.
R--27 to 30 inches; hard highly fractured sandstone.
TYPE LOCATION: San Luis Obispo County, California; 2,620 feet north and 1310 feet east of the southwest corner of Sec. 26, T.31S., R.18E., USGS Branch Mountain Topographic Quadrangle; lat. 35 degrees, 11 minutes, 54 seconds N. and long. 120 degrees, 1 minute, 25 seconds W.
RANGE IN CHARACTERISTICS: Depth to a lithic contact is 20 to 40 inches. The soil between the depths of 8 and 20 inches is moist in all parts for 60 consecutive days between mid January and April. It is also moist in some part from November 15 to June 1 and is dry in all parts for about 150 days from June 1 to November 15. The mean annual soil temperature ranges from 60 to 68 degrees F. The soil is neutral to mildly alkaline throughout.
The A horizon has dry color of 10YR 5/3, 6/3, 6/4; 2.5Y 6/2 and moist color of 10YR 3/3, 3/4; 2.5YR 3/4. Clay content is 20 to 27 percent.
The B horizon has dry color of 10YR 6/3, 5/4, 6/4; 7.5YR 5/4, 6/4 and moist color of 10YR 3/3, 4/3, 3/4, 4/4; 7.5YR 3/4, 4/4. Gravel content is 0 to 35 percent by volume. Cobble content is 0 to 5 percent by volume. Textures are clay loam and gravelly clay loam in the lower part. Clay content is 28 to 35 percent.
COMPETING SERIES: These are the Ballard, Bohna, Chualar, Chuloak, Franciscan, Gilroy, Pinto, Shimmon, Soper and Tehachapi series. Ballard, Chualar, Pinto and Tehachapi soils are deep or very deep and occur on terrace positions. Bohna soils are deep to bedrock. Chuloak soils are very deep and occur on alluvial fans. Franciscan soils have A horizons that have 10 to 20 percent clay and are dry throughout for more than 165 days. Gilroy soils have hues of 7.5YR and 5YR in the A horizon and are dry throughout for 165 days. Shimmon and Soper soils are moderately deep to a paralithic contact.
GEOGRAPHIC SETTING: The Tajea soils are on hills and mountains and have slopes of 15 to 50 percent. The soils formed in material weathered from sandstone. Elevations are 2,100 to 2,700 feet. The climate is semi-arid with hot dry summers and cool moist winters. Mean annual precipitation is 10 to 20 inches. Mean January temperature is 49 degrees F and the mean July temperature is 77 degrees F. The mean annual temperature is 58 to 62 degrees F. The frost-free season ranges from 175 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gaviota, and Saltos (T) soils. Gaviota soils are on similar topographic positions to the Tajea soil but do not have argillic horizons and are shallow. Saltos soils are shallow and are on similar landscapes as the Tajea soil.
DRAINAGE AND PERMEABILITY: Well drained, medium or high runoff; moderately slow permeability.
USE AND VEGETATION: Used for livestock grazing. Vegetation is oaks with an understory of soft chess and filaree.
DISTRIBUTION AND EXTENT: Central California in the Caliente Range, MLRA 15. These soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: San Luis Obispo County, California, Carrizo Plain SSA, 1988.