LOCATION HURLBUT CA
The Hurlbut series consists of moderately deep, well drained soils formed in material weathered from metamorphosed sedimentary rock. Hurlbut soils are on mountains and have slopes of 2 to 75 percent. The mean annual precipitation is 65 inches and the mean annual air temperature is 48 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Dystroxerepts
TYPICAL PEDON: Hurlbut gravelly loam - on a southwest facing slope of 2 percent under ponderosa pine, sugar pine, red fir trees, greenleaf manzanita, prostrate manzanita and chinquapin at 5,500 feet elevation. (Colors are for dry soil unless otherwise stated. When described November 13, l974, the soil was dry throughout.)
0i--0 to 2 inches; litter and duff.
A--2 to 6 inches; reddish yellow (7.5YR 6/6) gravelly loam, yellowish red (5YR 5/6) moist; moderate medium subangular blocky and granular structure; soft, friable, slightly sticky and slightly plastic; common very fine and fine roots; common fine and very fine interstitial pores; 20 percent pebbles; moderately acid (pH 5.7); clear smooth boundary. (2 to 4 inches thick)
Bw1--6 to 19 inches; reddish yellow (7.5YR 7/8) gravelly silt loam, strong brown (7.5YR 5/8) moist; moderate medium and fine angular blocky structure; slightly hard, friable, sticky and slightly plastic; common medium and coarse roots; common fine interstitial and tubular pores; 20 percent pebbles; many thin clay films lining pores; moderately acid (pH 5.7); gradual wavy boundary. (9 to 21 inches thick)
Bw2--19 to 29 inches; reddish yellow (7.5YR 7/8) silt loam, reddish yellow (7.5YR 6/8) moist; weak medium angular blocky structure; slightly hard, friable, sticky and slightly plastic; common medium and coarse roots; common fine interstitial and tubular pores; 10 percent pebbles; common thin clay films lining pores; moderately acid (pH 5.7); clear smooth boundary. (9 to 11 inches thick)
Cr--29 to 53 inches; weathered metamorphosed sedimentary rock, few medium and coarse roots in fractures 5 to 15 inches apart.
TYPE LCOATION: Placer County, Tahoe National Forest, California; 23 miles northeast of Foresthill, 000.2 mile east of the intersection of American Hill Road and Secret Ridge Road; near the southeast corner of section 1, T.15 N., R.12 E., M.D.B.M
RANGE IN CHARACTERISTICS: Depth to a paralithic contact is 20 to 40 inches. The mean annual soil temperature at 20 inches is 47 degrees to 55 degrees F. The soils are usually moist but are dry in all parts from July until November. Most pedons have up to 30 percent gravel with the larger amounts in the uppermost horizons. Base saturation is 30 to 50 percent throughout the soil.
The A horizon is 5YR 3/4; 7.5YR 4/6, 5/4, 5/6, 6/2, 6/4, 6/6; 10YR 4/3, 6/6, 6/4, 6/3, 5/4 dry and 5YR 4/6, 5/6; 7.5YR 3/2, 3/4, 4/4, 4/6; 10YR 3/2, 3/3, 4/3 moist. It is gravelly loam or gravelly fine sandy loam. It has subangular blocky or granular structure. Reaction is medium to slightly acid.
The Bw horizon is 5YR 4/6, 4/4, 5/6, 6/6; 7.5YR 5/6, 7/8; 10YR 5/4, 6/6, 6/8, 7/6 dry and 5YR 4/6, 3/4, 5/6; 7.5YR 6/8, 5/8, 5/6, 4/6, 4/4; 10YR 4/4, 5/6, 5/8, 6/6, 6/8 moist. It is silt loam, gravelly silt loam, gravelly loam or gravelly fine sandy loam with 18 to 27 percent clay. It has weak and moderate, fine through medium angular blocky structure. Some pedons have a C horizon above the paralithic contact. Reaction is medium to slightly acid.
COMPETING SERIES: These are the
Yeary and Schnorbush soils lack a paralithic contact. Hugo soils have a paralithic contact below a depth of 40 inches. Madonna soils have a lithic contact at depths of 20 to 40 inches.
GEOGRAPHIC SETTING: Hurlbut soils have slopes of 2 to 75 percent and are on mountains. They formed in material weathered from metamorphosed sedimentary rocks. Elevations are 1,200 to 5,500 feet. The climate is typified by warm dry summers and cool moist winters. Mean annual precipitation is 50 to 75 inches. Average January temperature is about 35 degrees F; average July temperature is about 68 degrees F; mean annual temperature is 45 degrees to 57 degrees F. Frost-free season is 100 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Smokey soils. Deadwood soils have a lithic contact within a depth of 20 inches and have more than 35 percent rock fragments in the control section. Mariposa soils have argillic horizons interrupted by bedrock and have a lithic contact at depth of 12 to 35 inches. Smokey soils have more than 35 percent rock fragments in the control section and have a frigid soil temperature regime.
DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; moderate permeability.
USE AND VEGETATION: Used mainly for timber production, also used for recreation, watershed protection and limited mining. Native vegetation is open, mixed stands of ponderosa pine, sugar pine, Douglas-fir, incense-cedar, white fir, black oak, greenleaf manzanita, and pinemat manzanita.
DISTRIBUTION AND EXTENT: The middle mountain area of the Sierra Nevada Mountains in California. The soils are extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Placer County (Tahoe National Forest), California 1975.
National Cooperative Soil Survey