LOCATION MUDHORSE CA

Established Series
Rev: BAL/ACF/ET
02/2019

MUDHORSE SERIES

The Mudhorse series consists of very deep, somewhat poorly drained soils formed in colluvium and residuum derived from sandstone and mudstone. These soils are on mountains and have slopes of 9 to 50 percent. Mean annual precipitation is 1500 millimeters (59 inches) and the mean annual temperature is 12 degrees C (54 degrees F).

TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Ultic Palexeralfs

TYPICAL PEDON: Mudhorse gravelly loam - under a stand of Oregon white oak and perennial and annual grasses at 1057 meters (3470 feet elevation). When described on July 1, 2004 the soil was dry throughout. (Colors are for dry soil unless otherwise stated).

Oi--0 to 4 centimeters (0 to 2 inches); very dark gray (10YR 3/1) slightly decomposed plant material; abrupt smooth boundary; moderately acid (pH 6.0). (0 to 15 centimeters thick)

A--4 to 12 centimeters (2 to 5 inches); brown (10YR 4/3) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to moderate fine granular; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium roots throughout; many very fine and fine tubular pores; 20 percent gravel; very strongly acid (pH 5.0); clear smooth boundary.(6 to 20 centimeters thick)

ABt--12 to 30 centimeters (5 to 12 inches); dark yellowish brown (10YR 4/4) loam, brown (10YR 4/3) moist; strong fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many fine and medium roots throughout; many very fine through medium tubular pores; common faint clay films on all faces of peds; 5 percent gravel; very strongly acid (pH 5.0); clear wavy boundary. (0 to 20 centimeters thick)

Bt--30 to 48 centimeters (12 to 19 inches); olive brown (2.5Y 4/4) clay loam, olive brown (2.5Y 4/4) moist; strong fine angular blocky structure; hard, firm, very sticky and very plastic; many fine and medium roots throughout; many very fine, and common fine and coarse tubular pores; common faint clay films on all faces of peds; 20 percent fine extremely weakly cemented yellowish red (5YR 4/6) iron-manganese masses;5 percent gravel; strongly acid (pH 5.1); clear wavy boundary. (15 to 50 centimeters thick)

Btg1--48 to 82 centimeters (19 to 32 inches); dark grayish brown (2.5Y 4/2) clay loam, very dark grayish brown (2.5Y 3/2), moist; strong fine and medium angular blocky structure; very hard, very firm, very sticky and very plastic; many fine and medium, and common coarse roots throughout; many medium and coarse tubular pores; few distinct clay films on all faces of peds; 40 percent fine very weakly cemented yellowish red (5YR 4/6) iron-manganese masses; 5 percent gravel; very strongly acid (pH 5.0); clear wavy boundary.

Btg2--82 to 130 centimeters (32 to 51 inches); very dark gray (2.5Y 3/1) clay loam, very dark gray (2.5Y 3/1) moist; moderate medium and coarse subangular blocky structure parting to strong very fine angular blocky; very hard, very firm, very sticky and very plastic; many fine roots throughout; many medium tubular pores; few distinct clay films on all faces of peds; 40 percent fine extremely weakly cemented yellowish red (5YR 4/6) iron-manganese masses; 5 percent gravel; strongly acid (pH 5.4); gradual wavy boundary.

Btg3--130 to 200 centimeters (51 to 79 inches); very dark gray (2.5Y 3/1) clay loam, very dark gray (2.5Y 3/1) moist; moderate medium and coarse subangular blocky structure parting to strong very fine angular blocky; very hard, very firm, very sticky and very plastic; many fine roots; many medium tubular pores; few distinct clay films on all faces of peds; 60 percent fine very weakly cemented yellowish red (5YR 4/6) iron-manganese masses; 5 percent gravel; strongly acid (pH 5.4). (Combined thickness of Btg horizons is 120 to 155 centimeters thick).

TYPE LOCATION: Humboldt County, California; Grouse Mountain USGS Quadrangle, CA.; WGS84 Decimal degrees latitude and -123.8425000 longitude; UTM Zone 10, 438084mE, 4520554mN, NAD 83.

RANGE IN CHARACTERISTICS:

Soil moisture: The soil moisture control section is usually moist in all parts from about November 1 to July 15, and is dry in all parts from about July 15 to October 15 in most years. The soils have a xeric moisture regime. A seasonal water table is present for 20 or more consecutive days or 30 or more cumulative days in most years within the zone from 30 to 50 centimeters (12 to 20 inches).

Soil temperature: The mean annual soil temperature is 10 to 15 degrees C (50 to 59 degrees F). The difference between the mean summer and mean winter temperature is 6 degrees C or greater. This soil has a mesic soil temperature regime.

Base saturation (by sum of cations) is 17 to 49 percent throughout the profile.

Soil reaction: very strongly acid to moderately acid throughout the soil profile.

Depth to redoximorphic features: 30 to 50 centimeters (12 to 20 inches).

Surface fragments: 0 to 5 percent gravel

Particle Size Control Section (weighted average):
Clay: 27 to 35 percent.
Rock fragments: 0 to 35 percent gravel.

A Horizon
Hue: 10YR or 2.5Y
Value: 3 or 4, dry or moist
Chroma: 2 or 3, dry or moist
Texture of fine earth fraction: loam
Clay content: 12 to 25 percent
Rock fragments: 0 to 35 percent gravel

Bt Horizons
Hue: 5Y, 2.5Y or 10YR
Value: 3 through 5 dry or moist
Chroma: 2 through 4 dry or moist
Texture of fine earth fraction: clay loam or silty clay loam
Clay content: 27 to 35 percent
Rock fragments: 0 to 35 percent gravel

Btg Horizons
Hue: 5Y, 2.5Y or 10YR
Value: 3 through 5 dry or moist
Chroma: 1 or 2, dry or moist
Texture of fine earth fraction: silty clay loam, clay loam, silty clay, or clay
Clay content: 35 to 45 percent
Rock fragments: 0 to 35 percent gravel

Redoximorphic features: fine, medium, and coarse iron-manganese masses in the matrix
Quantity: none to many
Hue: 7.5YR, 10YR, 2.5Y
Value: 3 through 5 moist
Chroma: 3 through 6 moist

COMPETING SERIES: These are the Featherfalls, Jafa, and Weaverville soils. Featherfalls, Jafa, Schaad,and Weaverville soils have redoximorphic features at depth greater than 100 centimeters.

GEOGRAPHIC SETTING: These soils occur on mountain slopes with slopes of 9 to 50 percent. They occur in concave positions at elevations of 35 to 1200 meters (115 to 3937 feet). These soils formed in colluvium and residuum derived from sandstone and mudstone. The climate is subhumid with warm, dry summers and cool, wet winters. The mean annual precipitation is 1250 to 2030 millimeters (49 to 80 inches). Mean annual air temperature is about 12 degrees C (54 degrees F). Mean summer temperature is 14 degrees C (58 degrees F) and the mean winter temperature is 7 degrees C (44 degrees F), and the mean annual temperature is 10 to 15 degree C. The frost free period is about 150 to 250 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Highoaks and Noisy soils. Highoaks soils are well drained with redoximorphic features greater than 100 centimeters (40 inches) from the soil surface. The Noisy soils are loamy-skeletal with greater than 35 percent rock fragments in the particle size control section. The Highoaks soils are generally on linear slope positions. The Noisy soils are generally on slightly to strongly convex slope positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained; high to very high runoff; moderately low saturated hydraulic conductivity. A seasonal water table is present for 20 or more consecutive days or 30 or more cumulative days in most years within the zone from 30 to 50 centimeters (12 to 20 inches).

USE AND VEGETATION: Used for grazing, watershed and wildlife habitat. Native vegetation is Oregon white oak with an understory of bristly dog tail grass, poison oak, creeping snowberry, and woodland strawberry.. Douglas-fir readily invades in the absence of fire.

DISTRIBUTION AND EXTENT: Siskiyou-Trinity Area, MLRA 5. The name is coined. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Humboldt Del Norte area, California, 2007.

REMARKS: Diagnostic horizons and features include:

1. Ochric horizon - the zone from 0 to 30 centimeters (Oi and A horizons)
2. Argillic horizon - the zone from 30 to 200 centimeters (Bt, Btg1, Btg2, and Btg3 horizons)
3. Particle size control section - the zone from 30 to 80 centimeters, (Bt2 and Bt3 horizons)averaging 34 percent clay and 5 percent rock fragments.

ADDITIONAL DATA:

NASIS User Pedon ID: 04CA023605039

NSSL pedon number: 05N0644

Soil classified using Keys to Soil Taxonomy, 12th edition. The classification was changed in 2008 from an Oxyaquic Palehumults to an Ultic Palexeralfs after the lab data was complete.

National Cooperative Soil Survey
U.S.A.