LOCATION REDWOHLY CA

Established Series
REV: JWH/JTW/ET
07/2016

REDWOHLY SERIES

The Redwohly series consists of very deep, well drained soils formed in residuum derived from mudstone and sandstone. Redwohly soils are 50 to 100 centimeters deep to paralithic bedrock material with cracks closer than 10 centimeters apart. Redwohly soils are on mountains. Slopes range from 15 to 75 percent. Mean annual precipitation is about 2160 millimeters and the mean annual temperature is about 11 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, isomesic Ultic Haplustalfs

TYPICAL PEDON: Redwohly gravelly loam on a northeast facing 23 percent slope under Douglas-fir, tanoak, and Pacific madrone at an elevation of 512 meters. (Colors are for dry soil unless otherwise noted.) When described on 06/23/2005, the soil was slightly moist throughout.

Oi--0 to 2 centimeters; 75 percent very dark brown (7.5YR 2.5/2) and 25 percent pinkish gray (7.5YR 6/2) slightly decomposed plant material, black (7.5YR 2.5/1) rubbed; about 75 percent fiber, 50 percent rubbed; 1 percent gravel; moderately acid (pH 6.0); abrupt smooth boundary. (0 to 10 centimeters thick); abrupt wavy boundary. (0 to 10 centimeters thick)

A--2 to 20 centimeters; brown (10YR 5/3) gravelly loam, dark brown (7.5YR 3/2) moist; moderate medium granular structure; moderately hard, friable, slightly sticky and slightly plastic; common very fine, fine, and medium roots throughout; 12 percent gravel, 5 percent paragravel1; slightly acid (pH 6.4); abrupt smooth boundary. (2 to 25 centimeters thick)

Bt1--20 to 50 centimeters; yellowish brown (10YR 5/4) gravelly loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; moderately hard, friable, moderately sticky and moderately plastic; common very fine, fine, medium, and common coarse roots throughout; common very fine tubular pores; 10 percent faint clay films on all faces of peds; 10 percent gravel, 5 percent paragravel; moderately acid (pH 5.6); gradual wavy boundary.

Bt2--50 to 70 centimeters; pale brown (10YR 6/3) paragravelly loam, dark yellowish brown (10YR 4/4) moist; moderate fine subangular blocky structure; moderately hard, friable, moderately sticky and moderately plastic; common medium roots throughout; 5 percent faint clay films on all faces of peds; 25 percent paragravel; moderately acid (pH 5.6); gradual wavy boundary. (Combined thickness of the Bt horizons is 15 to 98 centimeters thick)

C--70 to 180 centimeters; paragravel; few very fine and fine roots within cracks; paralithic materials, bedrock with cracks closer than 10 centimeters apart; 95 percent moderately cemented angular mudstone paragravel.

TYPE LOCATION: Humboldt County, California; about 2.5 kilometers north of Miranda, CA; USGS Myer's Flat Quadrangle; WGS84 Decimal degrees 40.2601528 latitude and -123.8215528longitude; UTM zone 10 0430139mE, 4456956mN; 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 temperatures is less than 6 degrees C. The soil has an isomesic soil temperature regime.

Soil Moisture: The soil moisture control section is dry in some or all parts for 90 or more cumulative days in normal years and it is moist in some part for more than 180 cumulative days or for 90 or more consecutive days per year. The soil has an ustic soil moisture regime.

Depth to paralithic bedrock material with cracks closer than 10 centimeters apart: 50 to 100 centimeters

Base Saturation: Less than 75 by sum of cations in one or more horizons within the upper 75 centimeters of the argillic

Surface Fragments: 0 to 34 percent gravel, 0 to 5 percent cobbles.

Particle-size control section (weighted average):
Clay content: 18 to 30 percent clay
Rock fragments: 0 to 34 percent
Pararock fragments: 5 to 59 percent

A horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6, 2 to 4 moist
Chroma: 2 to 4, dry or moist
Clay content: 12 to 25 percent
Rock fragments: 0 to 34 percent strongly cemented sandstone or mudstone gravel
Pararock fragments: 0 to 34 percent moderately cemented sandstone or mudstone paragravel
Reaction: strongly to slightly acid

Bt horizons:
Hue: 10YR or 2.5YR
Value: 5 or 6, 4 or 5 moist
Chroma: 3 or 4, dry or moist
Texture of fine earth: loam, sandy loam, silt loam, sandy clay loam,
silty clay loam, and clay loam,
Clay content: 18 to 34 percent
Rock fragments: 0 to 34 percent strongly cemented mudstone or sandstone gravel, 0 to 14 cobbles
Pararock fragments: 0 to 75 percent moderately cemented mudstone or sandstone paragravel, 0 to 34 percent paracobbles
Reaction: strongly to moderately acid

C horizons:
Hue: 10YR or 2.5Y
Value: 5 to 7, 4 to 6 moist
Chroma: 3 or 4, dry or moist
Texture: paragravel, paracobbles
Pararock fragments: 35 to 95 percent moderately cemented mudstone or sandstone paragravel, 0 to 59 percent paracobbles

COMPETING SERIES: These are the Crispin and Ornbaun soils. Crispin soils are formed in marine sediments on old marine terraces and lack fractured bedrock within 200 centimeters. Ornbaun soils have a paralithic contact between 100 and 150 centimeters.

GEOGRAPHIC SETTING: Redwohly soils are on convex positions on mountain slopes and ridges. Slopes are 15 to 75 percent. Elevations are 60 to 1000 meters. These soils formed in residuum derived from sandstone and mudstone. The climate is subhumid with warm, dry summers with a marine layer influence and cool, wet winters. Mean annual precipitation is 1525 to 3050 millimeters. The mean annual temperature is 10 to 12 degrees C. The frost-free period is 240 to 280 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Sproulish (CA) and Canoecreek (CA) soils. Sproulish soils lack paralithic materials within 200 centimeters. Canoecreek soils contain more than 35 percent rock fragments in the particle size control section. Sproulish soils are on linear to concave or slightly convex positions and Canoecreek soils are on linear to slightly concave or convex positions on mountain slopes and ridges.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high runoff; moderately high to moderately low saturated hydraulic conductivity.

USE AND VEGETATION: This soil is used for timber production, wildlife habitat, and watershed. Natural vegetation includes Douglas-fir, tanoak, Pacific madrone, and California huckleberry. When present, redwood is less than 50 percent.

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 coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon: The zone from 0 to 20 centimeters. (Oi and A horizons)
2. Argillic horizon: The zone from 20 to 70 centimeters. (Bt1 and B2t horizons)
3. Particle size control section: The zone from 20 to 70 centimeters averages 25 percent clay and 35.2 percent fine sand and coarser, by weight, 16 percent gravel, and 3 percent paragravel by volume.
(Bt1 and Bt2 horizons)
4. Paralithic materials: The zone from 70 to 180 centimeters (C horizon)
5. Ultic Haplustepts subgroup: the zone from 20 to 180 centimeters is less than 60 percent base saturation (by sum of cations) throughout.

ADDITIONAL DATA: Similar to NSSL Pedon No. 08N0575

NASIS User Pedon ID: 07CA601859

Keys to Soil Taxonomy, 12th edition.

National Cooperative Soil Survey
U.S.A.