LOCATION SCARIBOU CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, active, frigid Ultic Palexeralfs
TYPICAL PEDON: Scaribou very gravelly sandy loam, forested, on a 29 percent east-facing slope under mixed conifers and shrubs at 5,400 feet elevation. (When described September 11, 1984, the soil was dry from the mineral surface to a depth of 50 inches and slightly moist from 50 to 60 inches. The soil temperature at 20 inches was 49 degrees F. Colors are for dry soil unless otherwise noted).
Oi--2 to 0 inches; litter of needles, twigs and cones; abrupt smooth boundary.
A--0 to 3 inches; brown (7.5YR 5/2) very gravelly sandy loam, dark brown (7.5YR 3/2) moist; moderate fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, fine and medium roots; many very fine interstitial pores; 20 percent 2 to 5 mm pebbles and 30 percent 5 to 75 mm pebbles; slightly acid (pH 6.5); clear wavy boundary. (3 to 6 inches thick)
BA1--3 to 12 inches; light brown (7.5YR 6/4) very gravelly sandy loam, brown (7.5YR 4/4) moist; moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, fine and medium, and few coarse roots; many very fine interstitial pores; 20 percent 2 to 5 mm pebbles and 30 percent 5 to 75 mm pebbles; slightly acid (pH 6.5); clear wavy boundary.
BA2--12 to 19 inches; pink (7.5YR 7/4) very gravelly sandy loam, brown (7.5YR 5/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine, fine, medium and coarse roots; common very fine interstitial pores; 20 percent 2 to 5 mm pebbles and 30 percent 5 to 75 mm pebbles; slightly acid (pH 6.5); clear wavy boundary. (The combined thickness of the BA horizon is 10 to 20 inches.
Bt1--19 to 34 inches; pink (7.5YR 7/4) very gravelly sandy clay loam, brown (7.5YR 5/4) moist; moderate coarse angular blocky structure; hard, very friable, sticky and plastic; few very fine, fine, medium and coarse roots; many very fine tubular pores; many moderately thick reddish yellow (7.5YR 6/6), strong brown (7.5YR 4/6) moist, clay films on peds; continuous thin clay films in pores; 20 percent 2 to 5 mm pebbles and 30 percent 5 to 75 mm pebbles; slightly acid (pH 6.1); clear wavy boundary.
Bt2--34 to 51 inches; reddish yellow (7.5YR 6/6) very gravelly clay loam, strong brown (7.5YR 4/6) moist; strong fine angular blocky structure; very hard, friable, very sticky and very plastic; few fine, medium and coarse roots; common very fine tubular pores; continuous thick clay films on peds and in pores; 20 percent 2 to 5 mm pebbles and 30 percent 5 to 75 mm pebbles; slightly acid (pH 6.1); clear wavy boundary.
Bt3--51 to 60 inches; reddish yellow (7.5YR 6/6) very gravelly clay loam, strong brown (7.5YR 4/6) moist; strong medium angular blocky structure; very hard, friable, very sticky and very plastic; few fine roots; common very fine tubular pores; continuous thick clay films on peds and continuous moderately thick clay films in pores; common fine black stains; 20 percent 2 to 5 mm pebbles and 30 percent 5 to 75 mm pebbles; slightly acid (pH 6.1). (The combined thickness of the Bt horizons is 40 to 60 inches)
TYPE LOCATION: Lassen County, California; about 6.0 miles NE of Westwood; 1.5 miles N of HWY 36 on first road E of Coppervale and 250 feet W of this road; about 100 feet E and 1,000 feet S of NW corner of section 19, T.29 N., R.10 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature varies from 44 to 46 degrees F. The moisture control section (19 to 53 inches) is dry from August 1 to November 1 (90 days) and is moist in some or all parts the rest of the time. The soil temperature exceeds 41 degrees F from May 1 to December 1 and exceeds 47 degrees F from June 1 to November 1. Rock fragments on the surface range from 0 to 50 percent stones and 20 to 40 percent gravel.
The A horizon dry color is 7.5YR 4/4, 5/2, 5/3, 6/4 or 6/6. Moist color is 7.5YR 3/2, 4/4 or 4/6. It is very gravelly sandy loam, very gravelly loam, stony loam or extremely stony loam.
The BA horizon dry color is 7.5YR 5/4, 6/4, 6/6, 7/4 or 5 YR 6/6. Moist color is 7.5YR 4/4, 5/4, 5/6 or 5 YR 4/6. It is very gravelly sandy loam or very cobbly or extremely cobbly loam with 15 to 20 percent clay and 40 to 60 percent rock fragments.
The Bt horizon dry color is 7.5YR 5/4, 5/6, 5/8, 6/6, 7/4; 5YR 6/4, 6/6 or 7/6. Moist color is 7.5YR 3/4, 4/4, 4/6, 5/4; 5YR 4/6, 5/6, 5/8; 2.5YR 4/8 or 5/8. Reaction is slightly acid or neutral. It is very gravelly clay loam, very cobbly clay loam or very gravelly sandy clay loam with 27 to 35 percent clay and 35 to 60 percent rock fragments. Some pedons have texture of very gravelly clay below a depth of 40 inches. Clay content increases with increasing depth. Base saturation of the argillic horizon ranges from 35 to 65 percent.
COMPETING SERIES: These are the Penstock and Windego(T) series. Penstock soils have 18 to 27 percent clay in the control section. Windego soils are dry less than 80 days.
GEOGRAPHIC SETTING: Scaribou soils are on mountain sideslopes. Slopes are 5 to 75 percent. The soils formed in residuum and colluvium from nonmarine sediments or metavolcanics. Elevation is 4,400 to 6,800. The climate is subhumid with warm dry summers and cold moist winters. The mean annual precipitation is about 25 to 40 inches with 40 to 120 inches of snow. The mean annual temperature is about 44 degrees F., mean July temperature is about 60 degrees F. and mean January temperature is about 26 degrees F. The frost-free season is 60 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Almanor(T), Deadwood, Lasco(T), Swainow(T) and Weste(T) soils. Almanor soils are moderately deep to bedrock and are medial-skeletal. Deadwood soils are shallow to bedrock and have no argillic horizon. Lasco soils are coarse-loamy. Swainow soils have a mantle of volcanic ash and have 18 to 27 percent clay in the argillic horizon. Weste soils are moderately deep to bedrock and have 20 to 25 percent clay in the argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; runoff is rapid; moderately slow permeability.
USE AND VEGETATION: Scaribou soils are used for timber production. The vegetation is Jeffrey pine, Douglas fir, white fir, sugar pine, Incense cedar, whitethorn ceonothus, pinemat manzanita and squawcarpet.
DISTRIBUTION AND EXTENT: Northwestern Lassen County near Westwood, Ca. The soils of this series are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Lassen County, California, Susanville Area, Part of Lassen and Plumas Counties Soil Survey Area, 1985.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from the mineral soil surface to a depth of 19 inches (A, BA1 and BA2 horizons).
Argillic horizon: The zone from 19 to more than 60 inches (Bt1, Bt2 and Bt3 horizons).
Last revised by the state on 2/91.