LOCATION PETELLEN CA

Established Series
REV: SAA/ET
10/2016

PETELLEN SERIES

The Petellen series consists of very deep, well drained soils formed in colluvium and residuum derived from weakly consolidated conglomerate. Petellen soils are on mountains with slopes that range from 15 to 75 percent. The mean annual precipitation is about 1520 millimeters and the mean annual air temperature is about 11 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, isomesic Mollic Hapludalfs

TYPICAL PEDON: Petellen gravelly silt loam on a northwest facing 35 percent slope under coast redwood, red alder and coyotebrush at an elevation of 170 meters. (Colors are for moist soil unless otherwise stated.) When described on April 13, 2003 the soil was slightly moist to 162 centimeters.

Oi--0 to 5 centimeters, (0 to 2 inches); slightly decomposed plant material, very dark brown (10YR 2/2) crushed moist; slightly acid, pH 6.4 by Chlorophenol red; abrupt smooth boundary. (O horizon is 0 to 4 centimeters thick)

A--5 to 15 centimeters, (2 to 6 inches) very dark brown (10YR 2/2) broken face gravelly loam, grayish brown (10YR 5/2) dry; moderate fine subangular blocky structure, soft, very friable, nonsticky and nonplastic; many fine and very fine roots throughout; common very fine irregular pores; 20 percent rounded strongly cemented mixed gravel; slightly acid, pH 6.4 by Chlorophenol red; clear smooth boundary. (A horizon is 15 to 20 centimeters thick)

Bt1--15 to 35 centimeters, (6 to 14 inches ); dark brown (10YR 3/3) broken face very gravelly sandy clay loam, grayish brown (10YR 5/2) dry; moderate fine angular blocky structure; soft, friable, slightly sticky and slightly plastic; many very fine, fine, common medium and very coarse roots throughout; common very fine irregular pores; 5 percent faint clay films on all faces of peds; 25 gravel, 10 percent cobbles; slightly acid, pH 6.2 by Chlorophenol red; gradual smooth boundary.

Bt2--35 to 55 centimeters, (14 to 22 inches); dark brown (10YR 3/3) broken face very gravelly sandy clay loam, light brownish gray (10YR 6/2) dry; moderate medium angular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, common medium, and coarse roots throughout; common very fine irregular pores; 15 percent faint clay films on all faces of peds; 40 percent gravel and 10 percent cobbles; moderately acid, pH 6.0 by Chlorophenol red; gradual smooth boundary.

Bt3--55 to 82 centimeters, (22 to 32 inches ); brown (10YR 4/3) broken face very gravelly sandy clay loam, pale brown (10YR 6/3) dry; moderate medium angular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common fine and common very fine roots throughout; common very fine irregular pores; 20 percent faint clay films on all faces of peds; 50 percent gravel and 10 percent cobbles; moderately acid, pH 5.8 by Chlorophenol red; gradual wavy boundary.

Bt4--82 to 94 centimeters, (32 to 37 inches ); yellowish brown (10YR 5/4) very gravelly sandy clay loam, very pale brown (10YR 7/3) dry; strong medium angular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common fine and very fine roots throughout; common very fine irregular pores; 25 percent faint clay films on all faces of peds; 40 percent gravel and 10 percent cobbles; moderately acid, pH 5.8 by Chlorophenol red; gradual wavy boundary. (Combined thickness of the Bt horizon is 79 to 129 centimeters)

Cd--94 to 162 centimeters, (37 to 64 inches); yellowish brown (10YR 5/4) extremely gravelly loam, very pale brown (10YR 7/3) dry; 15 percent fine distinct yellowish brown (10YR 5/6) mottles; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine and coarse roots throughout; common very fine interstitial pores; 25 percent distinct clay films on rock fragments; 60 percent gravel and 15 percent cobbles; 15 percent ferruginous coating of densic material binding coarse fragments; moderately acid, pH 5.8 by Chlorophenol red. (Cd horizon is 0 to 68 centimeters thick)

TYPE LOCATION: Humboldt County, California; located about 3.2 kilometers east of the town of Carlotta, on Cuddeback Creek, tributary to the Van Duzen River; USGS Hydesville Quadrangle, CA; UTM zone 10, WGS84 Decimal degrees 40.5400000 latitude and -124.0286750 longitude; UTM zone 10 412966e, 4488005e; NAD 83

RANGE IN CHARACTERISTICS:

Soil Temperature: The mean annual soil temperature at 50 centimeters is 9 to 11 degrees C. (48 to 51 degrees F) and the difference between mean summer and mean winter soil temperature is less than 6 degrees C. The soil has an isomesic soil temperature regime.

Soil Moisture: The soil moisture control section is not dry in any part for 90 as long as 90 cumulative days in normal years. The soil has an udic soil moisture regime.

Colors meeting all the requirements for a mollic epipedon are 18 to 49 centimeters thick.

Surface Fragments: 0 to 25 percent strongly cemented rounded gravel.

Particle size control section (weighted average):
Rock fragments: 35 to 65 percent strongly cemented gravel, 0 to 60 percent strongly cemented cobbles
Clay content: 18 to 34 percent

A horizons:
Hue: 7.5YR or 10YR
Value: 2 or 3 moist, 4 or 5 dry,
Chroma: 2 or 3 moist or dry
Texture of fine earth: loam or silt loam
Rock fragments: 10 to 59 percent strongly cemented gravel, 0 to 5 percent strongly cemented cobbles
Clay content: 18 to 26 percent
Reaction: slightly acid to neutral

Upper Bt horizons:
Hue: 7.5YR or 10YR
Value: 3 through 5 moist, 4 through 6 dry
Chroma: 2 through 4 moist or dry
Texture of fine earth: loam through silty clay loam
Rock fragments: 25 to 65 percent strongly cemented gravel, 0 to 59 percent strongly cemented cobbles
Clay content: 20 to 32 percent
Reaction: strongly to slightly acid

Lower Bt horizons:
Hue: 7.5YR, 10YR, and 2.5Y
Value: 4 or 5 moist,5 through 7 dry
Chroma: 3 or 4 moist, 2 through 4 dry
Texture of fine earth: loam through silty clay loam
Rock fragments: 25 to 75 percent strongly cemented gravel, 0 to 75 percent strongly cemented cobbles
Clay content: 20 to 40 percent
Reaction: strongly to slightly acid

Cd horizons:
Hue: 7.5YR, 10YR, and 2.5Y
Value: 4 or 5 moist, 5 through 7 dry
Chroma: 3 or 4 moist, 2 to 4 dry
Texture of fine earth: loamy coarse sand through coarse sandy loam
Rock fragments: 35 to 85 percent strongly cemented gravel, 0 to 60 percent strongly cemented cobbles; 10 to 25 percent ferruginous coating of densic material binding coarse fragments
Clay content: 4 to 20 percent
Reaction: strongly to slightly acid

COMPETING SERIES: This is is the Dipsea series. Dipsea soils are 100 to 150 centimeters to a paralithic or lithic contact.

GEOGRAPHIC SETTING: Petellen soils are on summits, shoulders, and backslopes on mountain slopes and ridges. Slopes are 15 to 75 percent. Elevations are 10 to 450 meters. These soils formed in colluvium and residuum derived from weakly consolidated conglomerate. The climate is humid with cool, foggy summers and cool, wet winters. Mean annual precipitation is 1000 to 2160 millimeters. Mean January temperature is about 9 degrees C, mean July temperature is about 14 degrees C, and the mean annual temperature is 10 to 13 degrees C. Frost free season is about 240 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fiedler, Nanningcreek, Oeschger, and Scotiabluff soils. Fiedler, Nanningcreek, Oeschger, and Scotiabluff soils contain less than 35 percent rock fragments in the particle size control section. Nanningcreek soils have redoximorphic features between 50 and 100 centimeters of the mineral soil surface. Oeschger soils have less than 18 percent clay in the particle size control section. Scotiabluff soils are 50 to 100 centimeters to a paralithic contact, on ridges and linear to strongly convex mountain slopes.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, high runoff, moderately high saturated hydraulic conductivity.

USE AND VEGETATION: This soil is used for commercial timber production, wildlife habitat, and watershed. Natural vegetation includes coast redwood, Douglas-fir, Sitka spruce, grand fir, tanoak, red alder, blueblossom, coyotebrush, salal, California huckleberry, western swordfern, thimbleberry, and oxalis.

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 and Del Norte Counties Soil Survey, Central Part, California 2016. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon - the zone from 0 to 15 centimeters (Oi and A horizons)
2. Argillic horizon - the zone from 15 to 94 centimeters (Bt1, Bt2, Bt3 and Bt4, horizons).
3. Particle-size control section - the zone from 15 to 65 centimeters (Bt1, Bt2, and Bt3 horizons) averages 26 percent clay, by weight, and 46 percent rock fragments, by volume.
4. Densic material - the zone from 94 to 162 centimeters.

ADDITIONAL DATA:

Soil classified using the 12th edition Keys to Soil Taxonomy
NASIS User pedon ID 03CA600012

National Cooperative Soil Survey
U.S.A.