LOCATION VITZTHUM CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Lithic Haploxeralfs
TYPICAL PEDON: Vitzthum extremely gravelly loam--on a southeast facing, slightly convex slope of 50 percent under greenleaf manzanita and birchleaf mountainmahogany at an elevation of 3,600 feet. (Colors are for dry soil unless stated otherwise. When described on July 28, 1982 the soil was dry throughout). The soil surface is partially covered with 75 to 100 percent pebbles.
Oi--1 to 0 inches; leaves and twigs.
A--0 to 3 inches; dark yellowish brown (10YR 4/4) extremely gravelly loam, dark yellowish brown (10YR 3/4) moist; moderate fine and very fine subangular blocky structure; slightly hard, friable; slightly sticky and slightly plastic; common fine and very fine roots; common fine and very fine tubular pores; 60 percent pebbles; slightly acid (pH 6.5); clear wavy boundary. (2 to 3 inches thick).
Bt1--3 to 9 inches; brown (7.5YR 5/4) extremely gravelly sandy clay loam, brown (7.5YR 4/4) moist; strong medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium, fine and very fine roots; many medium, fine and very fine tubular pores; few thin clay films lining pores; 60 percent pebbles; slightly acid (pH 6.5); gradual wavy boundary. (5 to 7 inches thick).
Bt2--9 to 13 inches; strong brown (7.5YR 5/6) extremely gravelly sandy clay loam, brown (7.5YR 4/4) moist; moderate medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and plastic; few coarse, medium, fine, and very fine roots; common medium, fine and very fine interstitial pores; common thin clay films lining pores and on ped faces; 70 percent pebbles; slightly acid (pH 6.3); gradual wavy boundary. (3 to 5 inches thick).
Bt3--13 to 17 inches; strong brown (7.5YR 5/6) extremely gravelly sandy clay loam, brown (7.5YR 4/4) moist; strong medium and fine subangular blocky structure; slightly hard, friable, sticky and plastic; few coarse, medium, fine, and very fine roots; common medium, fine, and very fine interstitial pores; many thin clay films lining pores and on ped faces; 60 percent pebbles; slightly acid (pH 6.3); abrupt wavy boundary. (0 to 4 inches thick).
R--17 to 19 inches; hard, fractured metavolcanic rock. Fractures 1 to 2 inches apart, with roots extending down some fractures. Surface inch of rock is more weathered.
TYPE LOCATION: Trinity County, California; about 7.5 miles southeast of Douglas City, California; take Deer Lick Springs Road south to dirt road up Horse Mane Creek, turn east, go 2.9 miles up Horse Mane Creek, take left fork, go 1.2 miles to ridgetop, take sharp left (west) up the ridgetop, go 0.1 mile, pedon described 200 feet downhill; 400 feet north, and 900 feet west of the southeast corner of section 8, T.31 N., R.9 W. Hoosimbim Mtn. Quadrangle.
RANGE IN CHARACTERISTICS: Depth to bedrock ranges from 10 to 20 inches. The mean annual soil temperature ranges from 52 to 59 degrees F. The soil moisture control section between the depths of 12 and 17 inches is dry in all parts from about June 15 to October 10 (100 to 120 days). The soil temperature at 20 inches exceeds 41 degrees F from about February 15 to December 15 (305 days), and exceeds 47 degrees F from about March 1 to December 1.
The A horizon is 7.5YR 5/4, 6/4, 4/6, 10YR 4/4, or 5/4. Moist color is 10YR 3/4, 4/4, 7.5YR 3/2, 3/4, or 4/4. It is very gravelly loam or extremely gravelly loam. It is slightly acid or neutral.
The Bt horizon is 7.5YR 5/4, 5/6, 6/6, 7/6 or 10YR 5/4. Moist color is 7.5YR 4/4, 3/4, 4/6, 10YR 5/8, or 4/4. It is very gravelly loam, extremely gravelly clay loam, or extremely gravelly sandy clay loam. The Bt contains 40 to 70 percent rock fragments and 20 to 30 percent clay.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: The Vitzthum soils are on mountains. Elevation is 1,700 to 4,200 feet. Slopes are 50 to 75 percent. These soils formed in residuum and colluvium weathered from metamorphic rocks. The climate is characterized by warm, dry summers and cool, moist winters. Mean annual precipitation is about 30 to 60 inches. Snowfall ranges from about 6 to 36 inches. Mean January temperature is about 37 degrees F. Mean July temperature is about 70 degrees F. Mean annual temperature is about 50 to 57 degrees F. The frost-free period is 90 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Goulding, Caris, Vanvor, and Hoosimbim series. The Goulding and Caris soils lack argillic horizons. The Vanvor soils are 20 to 40 inches deep over a lithic contact. The Hoosimbim soils are 40 to 60 inches deep over a lithic contact.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; very rapid runoff; moderate permeability.
USE AND VEGETATION: The Vitzthum soil is used for watershed and wildlife habitat. Natural vegetation is greenleaf manzanita, canyon live oak, birchleaf mountainmahogany, wavyleaf ceanothus, and annual grasses.
DISTRIBUTION AND EXTENT: Klamath Mountains of northern California. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Trinity County, California, Weaverville Area, 1990. Name is from a local stream.
REMARKS: The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon--zone from the surface to 3 inches (A).
Argillic horizon--zone from 3 to 17 inches (Bt1, Bt2, Bt3). Determined by graphing.
Particle-size control section--zone from 3 to 17 inches (Bt1, Bt2, Bt3).