LOCATION JOHNNYJACK CA
Established Series
REV: JWH/JTB/KP
10/2016
JOHNNYJACK SERIES
The Johnnyjack series consists of very deep, well drained soils formed in alluvium derived from mixed sedimentary sources. Johnnyjack soils are on stream terraces in mountain river valleys. Slopes range from 0 to 2 percent. Mean annual precipitation is about 2030 mm and the mean annual temperature is about 14 degrees C.
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Cumulic Ultic Haploxerolls
TYPICAL PEDON: Johnnyjack silt loam on a northeast facing 1 percent slope under pasture grass at an elevation of 55 meters. (Colors are for dry soil unless otherwise noted.) When described on 5/04/05, the soil was moist throughout.
Ap--0 to 22 centimeters; brown (10YR 5/3) silt loam, very dark grayish brown (10YR 3/2) moist; strong very fine and fine subangular blocky structure; moderately hard, friable, slightly sticky and slightly plastic; many very fine and few fine roots; few fine and very fine tubular pores; 25 percent fine prominent dark yellowish brown (10YR 4/6) iron-manganese masses on surfaces along root channels; 3 percent gravel; very strongly acid (pH 4.9); clear smooth boundary.
A1--22 to 40 centimeters; brown (10YR 5/3) silty clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; moderately hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots throughout; many very fine, few fine and medium tubular pores; 1 percent gravel; strongly acid (pH 5.3); gradual smooth boundary. (Combined thickness of the A horizons is 50 to 100 centimeters)
A2--40 to 68 centimeters; grayish brown (10YR 5/2) silty clay loam, very dark gray (10YR 3/1) moist; weak fine and medium subangular blocky structure; moderately hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine, few fine and medium, and common coarse tubular pores; 2 percent gravel; strongly acid (pH 5.5); gradual smooth boundary.
Bw1--68 to 96 centimeters; light olive brown (2.5Y 5/3) silty clay loam, dark grayish brown (10YR 4/2) moist; weak fine and medium subangular blocky structure; moderately hard, friable, slightly sticky and moderately plastic; common very fine roots; many very fine, and few fine and medium tubular pores; 7 percent gravel; moderately acid (pH 5.6); gradual smooth boundary.
Bw2--96 to 122 centimeters; light yellowish brown (2.5Y 6/3) clay loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; moderately hard, friable, slightly sticky and moderately plastic; common very fine roots; many very fine, few fine and medium tubular pores; 11 percent gravel; moderately acid (pH 5.8); clear smooth boundary. (Combined thickness of the Bw horizons is 50 to 150 centimeters)
BC--122 to 152 centimeters; light yellowish brown (2.5Y 6/3) very gravelly loam, olive brown (2.5Y 4/3) moist; weak medium subangular blocky structure, and weak fine subangular blocky structure; moderately hard, friable, slightly sticky and moderately plastic; few very fine roots; common very fine and fine tubular pores; 36 percent gravel; moderately acid (pH 5.7); gradual smooth boundary. (0 to 50 centimeters thick)
C--152 to 200 centimeters; light yellowish brown (2.5Y 6/3) gravelly loam, olive brown (2.5Y 4/3) moist; massive; moderately hard, friable, slightly sticky and moderately plastic; 31 percent gravel; moderately acid (pH 5.8). (0 to 100 centimeters thick)
TYPE LOCATION: Humboldt County, California; about 11 kilometers northwest of the town of Honeydew; USGS Quadrangle Buckeye Mountain, CA; 40.2783333 latitude and -124.2458333 longitude; UTM Zone 10 394087mE, 4459390 mN; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is dry in all parts of the soil moisture control section for 45 or more consecutive days after the summer solstice and moist in all parts from November through May. The soils have a xeric moisture regime
Soil Temperature: The mean annual soil temperature at 50 centimeters is 15 to
18 degrees C and the difference between mean summer and mean winter soil temperatures is 6 degrees C or greater. The soil has a thermic temperature regime.
Mollic Epipedon: 50 to 100 centimeters
Base Saturation: 75 percent or less by sum of cations in one or more horizons between the Ap horizon and 75 centimeters
Particle size control section (weighted average):
Rock fragments: 0 to 10 percent
Clay content: 18 to 33 percent
A horizon:
Hue: 10YR or 2.5Y
Value: 3 to 5, 2 or 3 moist
Chroma: 1 to 3, moist or dry
Clay content: 15 to 27 percent
Rock fragments: 0 to 5 percent subrounded strongly cemented gravel
Reaction: strongly acid
Redoximorphic features: fine and medium iron-manganese masses due to compaction Quantity: none to common
Upper Bw horizon:
Hue: 10YR or 2.5Y
Value: 5 or 6, 3 or 4 moist
Chroma: 2 to 4, moist or dry
Texture: silt loam or silty clay loam
Clay content: 18 to 33 percent
Rock fragments: 0 to 10 percent subrounded strongly cemented gravel
Reaction: strongly to moderately acid
Lower Bw horizon:
Hue: 10YR or 2.5Y
Value: 5 or 6, 3 or 4 moist
Chroma: 2 to 4, moist or dry
Texture: silt loam, loam, fine sandy loam, or silty clay loam
Clay content: 18 to 33 percent
Rock fragments: 0 to 15 percent subrounded strongly cemented gravel
Reaction: moderately acid
Redoximorphic Features: fine and medium iron-manganese masses
Quantity: none to many
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 3 to 8
Redoximorphic features: fine and medium iron depletions
Quantity: none to common
Hue: 2.5Y or 5Y
Value: 4 or 5
Chroma: 1 or 2
C horizon (when present):
Hue: 10YR or 2.5Y
Value: 5 or 6, 3 or 4 moist
Chroma: 2 to 4, moist or dry
Texture: loam, sandy loam
Clay content: 5 to 30 percent
Rock fragments: 15 to 50 percent subrounded strongly cemented gravel
Reaction: moderately acid
Redoximorphic Features: fine and medium iron-manganese masses
Quantity: none to many
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 3 to 8
Redoximorphic features: fine and medium iron depletions
Quantity: none to common
Hue: 2.5Y or 5Y
Value: 4 or 5
Chroma: 1 or 2
COMPETING SERIES: This is the
Lupoyoma (CA) series. Lupoyoma soils have pH values greater than 6.0 and unprotected areas are subject to rare flooding.
GEOGRAPHIC SETTING: Johnnyjack soils are on linear to slightly concave positions on stream terraces. Slopes are 0 to 5 percent. Elevations are 18 to 100 meters. These soils formed in alluvium from mixed sedimentary rocks 18 degrees C and the difference between mean summer and mean winter soil temperatures is 6 degrees C or greater. The soil has a thermic temperature regime. The climate is subhumid with warm, dry summers with a marine layer influence and cool, wet winters. Mean annual precipitation is 1525 to 2500 millimeters. The mean annual temperature is 13 to 15 degrees C. Frost free season is about 240 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the
Conklin (CA) soil. Conklin soils have more than 15 percent (by weight) particles with diameters greater than 0.1 millimeters in the particle size control section. Conklin soils occur on linear to slightly convex positions on terraces.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; negligible to medium runoff; moderately low to moderately high saturated hydraulic conductivity.
USE AND VEGETATION: This soil is used mainly for pasture, hay, orchards, and irrigated vegetable crops. The vegetation is perennial and annual grasses and forbs including oats, soft brome, smooth brome, ryegrass, bristly dogstail grass, and foxtail.
DISTRIBUTION AND EXTENT: The series is not extensive. Coastal Redwood Belt MLRA 4B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Humboldt County, Southern part, Soil Survey, California, 2010.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Mollic epipedon: The zone from 0 to 68 centimeters. (Ap, A1, and A2 horizons)
2. Cambic horizon: The zone from 68 to 152 centimeters (Bw1, Bw2, and Bw3 horizons)
3. Particle size control section: The zone from 25 to 100 centimeters (A1, A2, Bw1, and Bw2 horizons) averages 31 percent clay and 8 percent fine sand or coarser, by weight, and 2 percent gravel, by volume.
4. Cumulic Feature: an irregular decrease in organic-carbon content in the zone between 22 and 96 centimeters (A1, A2, and Bw1 horizons)
ADDITIONAL DATA: NSSL Pedon No. 05N0651
Soil classified using Keys to Soil Taxonomy, 12th edition.
National Cooperative Soil Survey
U.S.A.