LOCATION PEPPERWOOD CA
Established Series
Rev.: JWH/JTB/ET
10/2016
PEPPERWOOD SERIES
The Pepperwood series consists of very deep, moderately well drained soils formed in alluvium derived from mixed sedimentary sources. Pepperwood soils are on flood-plain steps in mountain river valleys. Slope ranges from 0 to 2 percent. Mean annual precipitation is about 1500 millimeters and the mean annual temperature is about 13 degrees C.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, nonacid, thermic Oxyaquic Udifluvents
TYPICAL PEDON: Pepperwood fine sandy loam on a northwest facing, 0 percent slope under alfalfa, at an elevation of 50 meters. (Colors are for moist soil unless otherwise noted.) When described on June 23, 2006 the soil was moist throughout.
Ap--0 to 20 centimeters; very dark grayish brown (10YR 3/2) fine sandy loam, grayish brown (10YR 5/2) dry; moderate medium granular structure; moderately hard, very friable, nonsticky and nonplastic; common very fine, fine, and medium roots throughout; few very fine tubular pores; slightly acid (pH 6.2); abrupt smooth boundary. (Combined thickness of the A horizons is 5 to 80 centimeters thick)
C1--20 to 41 centimeters; dark grayish brown (10YR 4/2) stratified fine sandy loam, grayish brown (10YR 5/2) dry; massive; moderately hard, very friable, nonsticky and nonplastic; common very fine and common fine roots throughout; few very fine tubular pores; slightly acid (pH 6.3); clear smooth boundary.
C2--41 to 70 centimeters; dark olive brown (2.5Y 3/3) stratified very fine sandy loam, grayish brown (2.5Y 5/2) dry; massive; moderately hard, very friable, nonsticky and nonplastic; common very fine and fine roots throughout; few very fine tubular pores; neutral (pH 6.7); clear wavy boundary.
C3--70 to 79 centimeters; olive brown (2.5Y 4/3) stratified very fine sandy loam, grayish brown (2.5Y 5/2) dry; massive; moderately hard, very friable, nonsticky and nonplastic; common very fine and fine roots throughout; few very fine tubular pores; 5 percent medium distinct dark gray (2.5Y 4/1) moist iron-manganese masses in matrix and 10 percent medium distinct dark yellowish brown (10YR 4/4) moist iron-manganese masses in matrix; neutral (pH 6.6); clear wavy boundary.
Ab1--79 to 128 centimeters; very dark grayish brown (2.5Y 3/2) loam, grayish brown (2.5Y 5/2) dry; weak medium subangular blocky structure; extremely hard, friable, slightly sticky and slightly plastic; common very fine, fine, and medium roots throughout; few very fine and medium tubular pores; 30 percent distinct organic stains on surfaces along pores and on surfaces along root channels; 10 percent fine distinct dark gray (2.5Y 4/1) moist iron depletions in matrix and 25 percent fine distinct dark yellowish brown (10YR 4/4) moist iron-manganese masses in matrix; neutral (pH 6.7); clear wavy boundary.
Ab2--128 to 140 centimeters; very dark grayish brown (10YR 3/2) silt loam, gray (10YR 6/1) dry; weak fine subangular blocky structure; extremely hard, friable, slightly sticky and slightly plastic; few very fine and medium roots throughout; few very fine and medium tubular pores; 30 percent distinct organic stains on surfaces along pores and on surfaces along root channels; 10 percent medium distinct dark yellowish brown (10YR 4/4) moist iron-manganese masses in matrix; neutral (pH 6.6); clear wavy boundary. (Combined thickness of the Ab horizons is 0 to 50 centimeters thick)
C4--140 to 200 cm; dark brown (10YR 3/3) loam, grayish brown (10YR 5/2) dry; massive; moderately hard, very friable, nonsticky and nonplastic; few very fine and medium roots throughout; common very fine tubular pores; 2 percent medium distinct dark yellowish brown (10YR 3/4) moist iron-manganese masses in matrix; neutral (pH 6.7). (Combined thickness of the C horizons is 120 to 195 centimeters thick)
TYPE LOCATION: Humboldt County, California; about 5 kilometers south of the town of Redcrest on Camp Grant Flat; WGS84 Decimal degrees 40.3440611 latitude and -123.8901194 longitude; USGS Weott Quadrangle, CA; UTM Zone 10 424402mE, 4466326mN; NAD 83.
RANGE IN CHARACTERISTICS:
Soil Temperature: The mean annual soil temperature at 50 centimeters is 15 to 16 degrees C and the difference between mean summer and mean winter soil temperatures is 6 degrees C or greater. The soil has a thermic soil temperature regime.
Soil Moisture: The soil moisture control section is not dry in any part for as long as 90 cumulative days in normal years and is dry in all parts for less than 45 consecutive days in the 4 months following the summer solstice. The soil has a udic soil moisture regime.
Depth to Redoximorphic Features: 50 to 100 centimeters
Particle size control section (weighted average):
Rock fragments: 0 to 2 percent gravel
Clay content: 10 to 17 percent
A horizons:
Hue: 10YR or 2.5Y
Value: 3 or 4, 4 through 6 dry
Chroma: 2 or 3, moist or dry
Clay content: 10 to 17 percent
Rock fragments: 0 to 2 percent gravel
Reaction: moderately acid to slightly acid
C horizons:
Hue: 10YR or 2.5Y
Value: 3 or 4, 4 through 6 dry
Chroma: 2 or 3, moist or dry
Texture: very fine sandy loam, loam, fine sandy loam, sandy loam, and loamy sand
Clay content: 5 to 20 percent
Rock fragments: 0 to 5 percent gravel
Reaction: slightly acid to neutral
Redoximorphic Features: fine and medium iron-manganese masses
Quantity: none to many
Hue: 7.5YR, 10YR or 2.5Y
Value: 4 through 6
Chroma: 3 through 6
Redoximorphic features: fine and medium iron depletions
Quantity: none to common
Hue: 2.5Y or 5Y
Value: 4 or 5
Chroma: 1 or 2
Ab horizons:
Hue: 10YR or 2.5Y
Value: 2 or 3, 4 or 5 dry
Chroma: 1 through 3, moist or dry
Texture: silt loam or loam
Clay content: 10 to 20 percent
Rock fragments: 0 to 2 percent gravel
Reaction: slightly acid to neutral
Redoximorphic Features: fine and medium iron-manganese masses
Quantity: few to many
Hue: 7.5YR, 10YR or 2.5Y
Value: 4 through 6
Chroma: 3 through 6
Redoximorphic features: fine and medium iron depletions
Quantity: few to common
Hue: 2.5Y or 5Y
Value: 4 or 5
Chroma: 1 or 2
COMPETING SERIES: This is the
Tribbey series. Tribbey soils have C horizons with chromas greater than 3.
GEOGRAPHIC SETTING: Pepperwood soils are on linear to slightly convex positions on flood-plain steps in mountain river valleys. Slopes are 0 to 2 percent. Elevations are 18 to 170 meters. These soils formed in alluvium from mixed sedimentary sources. The climate is humid with cool, foggy summers and cool, wet winters. Mean annual precipitation is 1250 to 1780 millimeters. The mean annual temperature is 12 to 14 degrees C. Frost free season is about 280 to 350 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Cottoneva (CA),
Eelriver (CA), and
Shivelyflat (CA) soils. Cottoneva and Eelriver soils occur under native redwood forest where the difference between mean summer and mean winter soil temperature is less than 6 degrees C. Eelriver and Shivelyflat soils have less than 15 percent fine sand or coarser. Eelriver and Shivelyflat soils occur on linear to slightly concave positions on floodplain steps and natural levees. Cottoneva soils occur on the same positions as Pepperwood soils.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; high runoff; moderately high saturated hydraulic conductivity. The soils are rarely flooded for brief periods January through March. The soils are frequently ponded 1 to 3 centimeters deep for very brief periods December through April.
USE AND VEGETATION: This soil is used mainly for pasture and hay with small areas used for orchards, vinyards, and non-irrigated truck crops. Pasture vegetation includes wild oat, soft brome, ripgut brome, medusahead, bristly dogstail grass, and various forbs. These soils once supported redwood.
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, Southern Part, California, 2010. The name is from the town of Pepperwood.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon: The zone from 0 to 20 centimeters. (Ap horizon) Soil colors are determined to be lithochromic in nature.
2. Particle size control section: The zone from 25 to 100 centimeters (C1, C2, C3, and Ab1 horizons) averages 11 percent clay, and 33 percent fine sand or coarser.
3. Oxyaquic feature: The zone from 70 to 200 centimeters with iron-manganese masses (C3, Ab1, Ab2, and C4 horizons)
ADDITIONAL DATA: NASIS User Pedon ID: 06CA601602
NSSL Pedon No. 07N0350, Humboldt County, California, February, 2007. Selected horizons were run for NSSL Pedon No. 07N0355.
Soil classified using Keys to Soil Taxonomy, 12th edition.
National Cooperative Soil Survey
U.S.A.