LOCATION TANKRIDGE CA
Established Series
REV: JWH/JTB/ET
10/2016
TANKRIDGE SERIES
The Tankridge series consists of very deep, well drained soils formed in residuum derived from mudstone. Tankridge soils are moderately deep to paralithic bedrock materials with cracks closer than 10 centimeters apart. Tankridge soils are on mountains. Slopes range from 15 to 30 percent. Mean annual precipitation is about 2160 mm and the mean annual temperature is about 13 degrees C.
TAXONOMIC CLASS: Fine, mixed, superactive, thermic Ultic Haploxeralfs
TYPICAL PEDON: Tankridge silt loam on a southwest facing 20 percent slope under grassland, at an elevation of 213 meters. (Colors are for dry soil unless otherwise noted.) When described on May 5, 2005, the soil was moist to 200 cm.
A--0 to 14 centimeters; pale brown (10YR 6/3) silt loam, dark grayish brown (10YR 4/2) moist; moderate medium granular structure; hard, friable, slightly sticky and moderately plastic; common very fine roots throughout; very strongly acid (pH 4.6); abrupt smooth boundary. (5 to 25 centimeters thick)
Bt1--14 to 30 centimeters; pale brown (10YR 6/3) clay loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and moderately plastic; common very fine roots throughout; common very fine tubular pores; few distinct clay films on all faces of peds; strongly acid (pH 5.4); clear smooth boundary. (15 to 40) centimeters thick)
Bt2--30 to 52 centimeters; light yellowish brown (10YR 6/4) silty clay loam, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and moderately plastic; common very fine roots throughout; common very fine tubular pores; few distinct clay films on all faces of peds; moderately acid (pH 5.8); clear wavy boundary. (15 to 50 centimeters thick)
Ct--52 to 180 centimeters; light yellowish brown (10YR 6/4) paragravel, yellowish brown (10YR 5/4) moist; massive; common very fine roots in cracks; few distinct clay films around pararock fragments; paralithic materials, bedrock with cracks closer than 10 centimeters apart; 90 percent moderately cemented angular mudstone paragravel. (50 to 150 centimeters thick)
TYPE LOCATION: Humboldt County, California; about 2 kilometers east of Briceland on Old Briceland Road; USGS Briceland Quadrangle, California; WGS84 Decimal degrees 40.1047222 latitude and -123.8916667 longitude; UTM zone 10 424009mE, 4439773mN; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is dry in all parts for 45 or more consecutive days after the summer solstice and moist in all parts from November through May. The soil has a xeric soil moisture regime.
Soil Temperature: The mean annual soil temperature at 50 centimeters is 15 to 18 degrees C. The difference between mean summer and mean winter temperature is 6 degrees or more C. The soil has a thermic soil temperature regime.
Depth to paralithic materials, moderately cemented bedrock with cracks closer than 10 centimeters apart: 50 to 100 centimeters
Base Saturation: By sum of cations is less than 70 throughout the argillic
Particle-size control section (weighted average)
Rock fragments: 0 to 14 percent strongly cemented sandstone and mudstone gravel
Pararock fragments: 5 to 25 percent moderately cemented paragravel
Clay content: 35 to 40 percent clay
A horizon:
Hue: 10YR
Value: 5 through 7 (3 through 5 moist)
Chroma: 2 through 4
Clay content: 12 to 27 percent
Rock fragments: 0 to 5 percent
Reaction: very strongly to strongly acid
Bt horizons:
Hue: 10YR or 2.5Y
Value: 4 through 7 (3 through 5 moist)
Chroma: 2 through 4
Texture: silty clay loam or clay loam
Clay content: 30 to 40 percent
Rock fragments: 5 to 15 percent gravel
Pararock fragments: 5 to 25 percent paragravel
Reaction: moderately to strongly acid
C horizons:
Hue: 10YR or 2.5Y
Value: 5 or 6 (3 or 4 moist)
Chroma: 4 through 6, dry or moist
Texture: moderately cemented mudstone paragravel
Pararock fragments: 90 to 95 percent paragravel
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Tankridge soils are on convex positions on summits, shoulders, and backslopes of mountain slopes and ridges. Slopes are 15 to 30 percent. Elevations are 155 to 460 meters. These soils formed in residuum derived from mudstone.The climate is subhumid with warm, dry summers with a marine layer influence and cool, wet winters. Mean January temperature is about 7 degrees C, mean July temperature is about 22 degrees C, and the mean annual precipitation is 1525 to 3050 millimeters. The mean annual temperature is 12 to 14 degrees C. and the frost-free period is 240 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the
Briceland series. Briceland have less than 35 percent clay in the particle size control section and lack paralithic materials within 200 centimeters.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high runoff; moderately low saturated hydraulic conductivity.
USE AND VEGETATION: This soil is used mainly for livestock grazing, wildlife habitat, and watershed. Natural vegetation is California oatgrass, medusahead, and pennyroyal.
DISTRIBUTION AND EXTENT: Coastal Redwood Belt; MLRA 4B. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Humboldt County, South Part, California, 2010. The name is from Tank Ridge.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon: The zone from 0 to 14 centimeters. (A horizon)
2. Argillic horizon: The zone from 14 to 52 centimeters. (Bt1 and Bt2 horizons)
3. Particle size control section: The zone from 14 to 52 centimeters averages 36 percent clay, by weight, 5 percent rock fragments and 5 percent pararock fragments, by volume. (Bt1 and Bt2 horizons)
4. Paralithic materials: The zone from 52 to 180 centimeters (Ct horizon)
ADDITIONAL DATA: NSSC Pedon No. 05N0652 and similar to No. 06N0223 pararock study.
Keys to Soil Taxonomy, 12th edition.
National Cooperative Soil Survey
U.S.A.