LOCATION JOCAL CA
The Jocal series consists of very deep, well drained soils formed in material weathered from metasedimentary rocks. Jocal soils are on mountains and have slopes of 2 to 75 percent. The mean annual precipitation is 1360 mm and the mean annual air temperature is 12 degrees C.
TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Typic Haploxerults
TYPICAL PEDON: Jocal loam; under cover of Douglas fir, sugar pine, and ponderosa pine, on a north-facing, linear, 32 percent slope at an elevation of 1429 meters.
Oi--0 to 5 cm; decomposing fir litter.
A--5 to 15 cm; brown (7.5YR 4/4) loam, dark brown (7.5YR 3/4) moist; moderate fine granular structure; slightly hard, firm, slightly sticky and slightly plastic; common fine roots; many very fine interstitial pores; 10 percent gravel; moderately acid (pH 6.0); clear smooth boundary. (8 to 15 cm thick)
AB--15 to 43 cm; strong brown (7.5YR 5/6) silt loam, yellowish red (5YR 4/6) moist; strong fine granular structure; slightly hard, firm, slightly sticky and slightly plastic; common moderately thick clay films on ped faces and lining pores; common fine and medium roots; many very fine interstitial and common fine tubular pores; 5 percent gravel; moderately acid (pH 5.8); gradual smooth boundary. (0 to 40 cm thick)
Bt1--43 to 61 cm; reddish yellow (7.5YR 6/6) silty clay loam, yellowish red (5YR 5/6) moist; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; continuous thick clay films on ped faces and lining pores; few fine, common medium and coarse roots; common fine tubular pores; 5 percent gravel; moderately acid (pH 5.8); clear smooth boundary. (15 to 40 cm thick)
Bt2--61 to 119 cm; reddish yellow (7.5YR 6/6) silty clay loam, yellowish red (5YR 5/6) moist; moderate medium and coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; continuous thick clay films in pores and on ped faces; common medium and coarse roots; common very fine interstitial and common fine tubular pores; 5 percent gravel; moderately acid (pH 5.7); clear smooth boundary. (50 to 90 cm thick)
C--119 to 161 cm; reddish yellow (5YR 7/6) sandy clay loam, yellowish red (5YR 5/6) moist; massive; hard, firm, moderately sticky, moderately plastic; few coarse roots; few very fine interstitial pores; 5 percent gravel; moderately acid (pH 5.6). (25 to 60 cm thick)
TYPE LOCATION: El Dorado County, California; about 2 km (1.25 miles) north of Camp Seven, about 6 meters (20 feet) west of U.S. Forest Service Road 12N53; in the SE 1/4 of the SW 1/4, section 31, T.12 N., R.13 E. USGS 7.5 minute topographic quadrangle: Pollock Pines, California. WGS84 38.8387830 latitude and -120.5703130 longitude. UTM Zone 10 710881 meters E 4301691 meters N, NAD83.
RANGE IN CHARACTERISTICS:
Soil temperature: mean annual temperature at 50 cm depth is 8 to 15 degrees C. The difference between mean summer and winter soil temperature is greater than 6 degrees C. The soils have a mesic temperature regime.
Soil moisture: The soil moisture control section is dry in all parts from about June to October. The soils have a xeric moisture regime.
Ochric epipedon thickness: 15 to 50 cm
Argillic horizon thickness: 110 to over 150cm
Particle size control section weighted averages:
Clay content: 27 to 35 percent
Rock fragments: 0 to 35 percent gravel
Hue: 5YR, 7.5YR, 10YR
Value: 3 to 5 dry; 3 or 4 moist
Chroma: 2 to 6 dry; 2 to 4 moist
Textures: loam, silt loam
Clay content: 15 to 22 percent
Rock fragments: 0 to 25 percent gravel
Reaction: moderately acid to slightly acid
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 to 8 dry; 4 to 7 moist
Chroma: 6 to 8 dry; 4 to 8 moist
Textures: loam, sandy clay loam, silty clay loam, clay loam
Clay content: 24 to 40 percent
Rock fragments: 0 to 40 percent gravel
Reaction: very strongly acid to moderately acid
C horizon (when present)
Hue: 5YR, 7.5YR
Value: 4 TO 7 dry; 4 or 5 moist
Chroma: 6 or 8 dry or moist
Textures: silty clay loam, clay loam, sandy clay loam, silt loam
Rock fragments: 0 to 15 percent gravel
Clay content: 25 to 35 percent
Reaction: very strongly acid to moderately acid
COMPETING SERIES: These are the
Mac soils. Hietanen soils are 100 to 150 cm to a paralithic contact with metasedimentary rock. Mac soils are 50 to 100 cm to a paralithic contact with metamorphic rock.
GEOGRAPHIC SETTING: Jocal soils are on backslopes of mountain slopes. Slopes are 2 to 75 percent. The soils formed in material weathered from metasedimentary rock. Elevations are 800 to 1585 meters. The climate is warm, dry summers and cool, wet winters. Mean annual precipitation is 1235 to 1970 mm, of which 3 to 15 percent falls as snow. Snow covers the higher elevations from December until March. Mean annual air temperature is about 11 to 14 degrees C. Mean January temperature is about 4 degrees C; mean July temperature is about 24 degrees C. Frost-free season is about 170 to 225 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Sites soils. Fiddletown and Hartless soils do not have argillic horizons, have a lithic contact at 100 to 150 cm, and occur on backslopes and shoulders of mountain slopes. Horseshoe soils formed in gravelly Tertiary terrace remnants and basic volcanic rocks (dominantly andesitic tuff breccia) and occur on backslopes, summits or footslopes of broad tabular ridges. Mariposa soils occur in similar hillslope positions as Jocal and are 50 to 100 cm to a paralithic contact of metasedimentary rock. Sites soils have more than 35 percent clay in the upper argillic horizon, have parasesquic mineralogy, and occur on more stable backslopes and summits of mountain slopes.
DRAINAGE AND PERMEABILITY: Well drained; Saturated hydraulic conductivity is moderately low to moderately high.
USE AND VEGETATION: Used mainly for timber production, watershed, and wildlife habitat. Vegetation is typically mixed coniferous forest-shrub, with ponderosa pine, sugar pine, Douglas-fir, California black oak, whiteleaf manzanita and mountain misery.
DISTRIBUTION AND EXTENT: Sierra Nevada Mountains of California; MLRA 22A. The soils are extensive.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: El Dorado County, California (Eldorado National Forest), 1985.
Particle size control section for this pedon: 43 to 93 cm
Diagnostic horizons and features recognized in this pedon:
Ochric epipedon: 0 to 43 cm
Argillic horizon: 43 to 119 cm
Soils formerly mapped as Josephine series in Amador, Nevada, and Placer Counties, California would now be called Jocal.
Soils formerly mapped as Jocal in the deep depth class (100 to 150 cm to paralithic contact) would now be called Hietanen.
NASIS User Pedon ID: 1985CA017002
The soil was classified using the 12th edition of the Keys to Soil Taxonomy.
National Cooperative Soil Survey