LOCATION REDVINE CAEstablished Series
TAXONOMIC CLASS: Fine, mixed, semiactive, thermic Ultic Palexeralfs
TYPICAL PEDON: Redvine sandy clay loam - on a north-facing convex slope of 20 percent under a cover of manzanita, poison oak, and black oak at 1,040 feet elevation. (Colors are for dry soil unless otherwise stated. When described October 16, 1979, the soil was moist throughout).
A--0 to 3 inches; reddish brown (5YR 5/3) sandy clay loam, dark reddish brown (5YR 3/2) moist; strong fine and medium granular structure; hard, friable, slightly sticky and slightly plastic; many very fine and few medium and fine roots; common very fine tubular and many very fine interstitial pores; 7 percent 2 to 5 mm pebbles; slightly acid (pH 6.5); abrupt wavy boundary. (2 to 7 inches thick)
ABt--3 to 8 inches; variegated yellowish red and light grey (5YR 5/6, 10YR 7/2) sandy clay loam, reddish brown and pale brown (5YR 4/4, 10YR 6/3) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine and few medium roots; many very fine and fine, common medium and few coarse tubular pores; 5 percent 2 to 5 mm pebbles; few thin clay films in pores and on peds; slightly acid (pH 6.5); clear wavy boundary. (3 to 7 inches thick)
Bt1--8 to 14 inches; yellowish red (5YR 4/6) clay loam, dark reddish brown (2.5YR 3/4) moist; strong fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine and few medium roots; many very fine and fine and common medium tubular pores; 5 percent 2 to 5 mm pebbles; common moderately thick clay films in pores and on peds; slightly acid (pH 6.5); abrupt wavy boundary. (3 to 9 inches thick).
Bt2--14 to 30 inches; yellowish red (5YR 5/8) clay, dark red (2.5YR 3/6) moist; strong coarse prismatic structure parting to strong medium and coarse angular blocky; very hard, firm, sticky and plastic; common very fine and coarse and many fine and medium roots; common very fine and fine and few medium tubular pores; 7 percent 2 to 25 mm pebbles; continuous thick clay films in pores and on peds; strongly acid (pH 5.5); gradual wavy boundary. (12 to 20 inches thick).
Bt3--30 to 50 inches; yellowish red (5YR 5/8) clay, red (2.5YR 4/6) moist; strong fine and medium angular blocky structure; very hard, firm, sticky and plastic; common very fine through coarse roots; many very fine and fine tubular pores; 7 percent 2 to 25 mm pebbles; continuous thick clay films in pores and on peds; very strongly acid (pH 4.5); gradual smooth boundary. (16 to 24 inches thick)
Bt4--50 to 62 inches; variegated yellowish red and reddish yellow (5YR 5/8, 5YR 6/6) clay, variegated yellowish red and red (5YR 5/8, 2.5YR 4/6), yellowish red (5YR 5/8) crushed, moist; moderate fine and medium angular blocky structure; very hard, firm, sticky and plastic; common very fine and few fine roots; many very fine and common fine tubular pores; 7 percent 2 to 25 mm pebbles and highly weathered soft rock fragments; many thick clay films in pores and on peds; very strongly acid (pH 4.5)
TYPE LOCATION: Mendocino County, California; 1/2 mile north of Lake Mendocino; in a road cut on south side of Road A, 0.15 mile northwest of intersection of Roads A and B; 2,850 feet north and 5,700 feet west of the southwest corner of sec. 14, T. 16 N., R. 12 W., MDBM.
RANGE IN CHARACTERISTICS: The thickness of the solum and the depth to old alluvium is greater than 60 inches. The soil is dry between a depth of 7 to 20 inches in all parts from June to October in most years and usually moist in all parts from December to May. The mean annual soil temperature is 59 to 61 degrees F. The particle-size control section averages 35 to 50 percent clay and 0 to 10 percent rock fragments. Base saturation ranges from 30 to 75 percent (sum) throughout the profile, but is greater than 35 percent 1.25 meters below the top of the argillic horizon.
The A horizon is 5YR 5/3, 5/4, 5/6, 6/4; or 7.5YR 5/4. Moist colors are 5YR 3/2, 3/4, 4/4, 4/6, 5/6; 7.5YR 3/2 or 4/4. It is loam, sandy clay loam, or clay loam with 20 to 35 percent clay. It is strongly acid to slightly acid.
The Bt horizon is 2.5YR 3/6, 4/6; 5YR 3/6, 4/6, 5/4, 5/6, 5/8, 6/4, 6/6; 7.5YR 5/4 or 6/6. Moist colors are 2.5YR 3/4, 3/6, 4/6, 4/8; 5YR 3/4, 4/4, 4/6, 5/6, 5/8; 7.5YR 3/4, 4/4, 4/6, 5/4, 5/6 or 5/8. It is clay loam or clay with 30 to 60 percent clay. It is very strongly to slightly acid.
COMPETING SERIES: These are the Forbesville (T) series in the same family and the Cotati, Hellman (T), Manzanita, Pinnacles, Red Bluff, and Spreckels series in other families. Cotati and Spreckels soils have mesic soil temperatures. Forbesville soils have an abrupt textural increase of clay between the surface and the top of the argillic of 20 percent (absolute) within a vertical distance of 7.5 cm. Pinnacles soils have montmorillonitic mineralogy. Red Bluff and Spreckles series have kaolinitic mineralogy. Hellman soils have moist color values less than 3.5 throughout the upper 10 cm. Manzanita soils have fine-loamy particle-size control sections.
GEOGRAPHIC SETTING: The Redvine soils are on dissected terraces and have slopes of 2 to 30 percent. They formed in old alluvium from sedimentary rock at elevations of 500 to 1,400 feet. The climate is subhumid with hot dry summers and cool moist winters. Mean annual precipitation is 32 to 44 inches. Mean January temperature is 44 degrees F; mean July temperature is 72 degrees F; mean annual temperature is 57 to 59 degrees F. Frost-free season ranges from 200 to 225 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Pinole, Pinnobie (T), and Yokayo (T) soils. Pinole and Pinnobie soils have fine-loamy particle-size control sections. Yokayo soils have base saturation more than 75 percent in the upper 30 inches of the argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; slow permeability.
USE AND VEGETATION: Used for vineyards, orchards, and irrigated pasture. Natural vegetation was annual grasses, manzanita, poison-oak, black oak, and toyon. Most areas of this soil are cleared and cultivated.
DISTRIBUTION AND EXTENT: Northern California in Coast Range valleys. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Mendocino County, Eastern Part, California 1979. Soil name is coined.
ADDITIONAL DATA: NSSL Pedon S79CA-045-125 samples 80P-2931-2937. Lab data shows pedon as possibly halloysitic family.
REMARKS: Series should be reclassified as a Palexerult.