LOCATION MULECREEK CA
Established Series
REV: JWH/JTB/SAA/KP
10/2016
MULECREEK SERIES
The Mulecreek series consists of very deep, moderately well drained soils formed in alluvium derived from mixed sedimentary sources including sandstone and mudstone. Mulecreek soils are on stream terraces and alluvial fans in mountain river valleys. Slope ranges from 0 to 9 percent. The mean annual precipitation is about 1650 mm and the mean annual air temperature is about 8 degrees C.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Oxyaquic Argixerolls
TYPICAL PEDON: Mulecreek loam on a northeast facing slope of 3 percent under pasture. (Colors are for dry soil unless otherwise stated. When described on July 30, 2009, the soil was slightly moist below 90 centimeters.)
A1--0 to 10 centimeters; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine and very fine subangular blocky structure; very friable, moderately hard, slightly sticky and slightly plastic; few fine and many very fine roots throughout; common fine, medium, and very fine tubular pores; 3 percent gravel; moderately acid (pH 5.6); clear smooth boundary.
A2--10 to 55 centimeters; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; very friable, moderately hard, slightly sticky and slightly plastic; few fine and common very fine roots throughout; common fine, medium, and very fine vesicular pores; 3 percent gravel; moderately acid (pH 5.6); clear smooth boundary. (Combined thickness of the A horizon is 5 to 25 cm.)
Bt1--55 to 75 centimeters; brown (10YR 4/3) clay loam, pale brown (10YR 6/3) moist; moderate fine subangular blocky structure; very friable, moderately hard, moderately sticky and moderately plastic; few fine and very fine roots throughout; few fine, very fine, and medium tubular pores; 5 percent faint clay films on all faces of peds; 3 percent gravel; moderately acid (pH 5.6); clear smooth boundary.
Bt2--75 to 95 centimeters; very pale brown (10YR 7/3) clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; friable, moderately hard, moderately sticky and moderately plastic; few fine and very fine roots throughout; few fine and very fine tubular pores; 10 percent faint clay films on all faces of peds; 10 percent fine irregular strong brown (7.5YR 5/6) iron-manganese masses throughout; 3 percent gravel; moderately acid (pH 5.6); gradual smooth boundary.
Bt3--95 to 140 centimeters; light reddish brown (2.5YR 7/3) clay loam, reddish brown (2.5YR 5/4) moist; moderate fine and medium subangular blocky structure; friable, moderately hard, moderately sticky and moderately plastic; few fine and very fine tubular pores; 10 percent faint clay films on all faces of peds; 20 percent medium irregular strong brown (7.5YR 5/6) iron-manganese masses throughout; 3 percent gravel, moderately acid (pH 5.8); gradual smooth boundary. (Combined thickness of the Bt horizon is 150 to 180 cm.)
BCt--140 to 200 centimeters; light yellowish brown (2.5Y 6/3) clay loam, olive brown (2.5Y 4/3) moist; weak fine and medium subangular blocky structure; friable, moderately hard, moderately sticky and moderately plastic; few fine and very fine tubular pores; 5 percent faint clay films on all faces of peds; 10 percent medium irregular dark gray (2.5Y 4/1) iron depletions throughout and 20 percent medium irregular strong brown (7.5YR 5/6) iron-manganese masses throughout; 5 percent gravel; moderately acid (pH 6.0).(0 to 60 cm thick)
TYPE LOCATION: Humboldt County, California; 16.25 kilometers east of Bridgeville, Ca. on Route 36, then .1 kilometer east; USGS Larrabee Valley Quadrangle, CA.; WGS84 Decimal degrees 40.448167 latitude, -123.6901472 longitude; UTM zone 10 441476mE, 4477730mN; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is dry in all parts 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 average summer soil temperature is about 18 degrees C and the average winter soil temperature is about 6 degrees C. The soil has a mesic temperature regime.
Depth to Redoximorphic Features: 50 to 100 centimeters
Thickness of Mollic Epipedon: 25 to 125 centimeters
Particle size control section (weighted average):
Rock fragments: 0 to 35 percent gravel
Clay content: 24 to 35 percent
A horizon
Hue: 10YR or 2.5Y
Value: 4 or 5, 2 or 3 moist
Chroma: 1 to 3, dry or moist
Rock fragments: 0 to 15 percent gravel
Clay content: 15 to 27 percent
Reaction: strongly to slightly acid
Upper Bt horizons
Hue: 10YR or 2.5Y
Value: 5 to 7, 3 or 4 moist
Chroma: 2 to 4, dry or moist
Texture of fine earth: silt loam, silty clay loam, loam, clay loam, and sandy clay loam
Rock fragments: 0 to 34 percent gravel
Clay content: 18 to 34 percent
Reaction: strongly to moderately acid
Redoximorphic Features: fine and medium iron or iron-manganese masses in the matrix
Quantity: none to many
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 4 to 6
Lower Bt horizons
Hue: 10YR or 2.5Y
Value: 5 to 7, 3 to 5 moist
Chroma: 1 to 6, dry or moist
Texture of fine earth: clay loam, sandy clay loam, and clay
Rock fragments: 0 to 35 percent gravel and 0 to 5 percent cobbles
Clay content: 27 to 45 percent
Reaction: moderately to slightly acid
Redoximorphic Features: fine and medium iron or iron-manganese masses in the matrix
Quantity: few to many
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 4 to 6
Redoximorphic features: fine and medium iron depletions
Quantity: none to common
Hue: 10 YR or 2.5Y
Value: 4 or 5, moist
Chroma: 1 or 2, moist
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Mulecreek soils are on stream terraces or alluvial fans in mountain river valleys. Slopes are 0 to 9 percent. Elevations are 730 to 825 meters. These soils formed in slope alluvium derived from mixed sedimentary sources including 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 1780 millimeters. Mean annual air temperature is 7 to 9 degrees C. Frost free season is about 60 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the
Frostvalley soil. Frostvalley soils do not have redoxomorphic features within 200 centimeters of the mineral soil surface.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained, low or medium runoff, moderately high to moderately low saturated hydraulic conductivity.
USE AND VEGETATION: This soil is used for pasture and irrigated vegetable crops. Vegetation is annual and perennial grasses, pennyroyal, western rush, and other forbs.
DISTRIBUTION AND EXTENT: Coastal Redwood Belt; MLRA 5. 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 from Mule Creek.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Mollic epipedon - the zone from 0 to 55 centimeters (A1 and A2 horizons).
2. Argillic horizon - the zone from 55 to 200 centimeters (Bt1, Bt2, Bt3, and BCt horizons).
3. Oxyaquic conditions - the zone from 55 to 200 centimeters (Bt2, Bt3, and BCt horizons)
4. Particle size control section: the zone from 55 to 105 centimeters (Bt1, Bt2, and Bt3 horizons) averages 30 percent clay and 24 percent fine sand or coarser, by weight.
ADDITIONAL DATA:
NASIS User Pedon ID 09CA600362
Keys to Soil Taxonomy, 12th edition
National Cooperative Soil Survey
U.S.A.