LOCATION ROOP CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Vitrandic Dystroxerepts
TYPICAL PEDON: Roop very stony loam, forested, on a 39 percent N facing slope under white fir, Jeffery pine and manzanita at about 6400 feet elevation. (When described (8-5-85) the soil was dry throughout. Colors are for dry soil unless otherwise noted.)
O--2 inches to 0; decomposing fir needles and twigs; abrupt smooth boundary.
A1--0 to 5 inches; brown (10YR 5/3) very stony loam, dark brown (10YR 3/3) moist; weak very fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine interstitial pores; 15 percent stones, 15 percent cobbles; 20 percent pebbles; medium acid (pH 5.8); clear wavy boundary.
A2--5 to 13 inches; brown (10YR 5/3) very gravelly sandy loam, dark brown (10YR 3/3) moist; weak very fine and fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine and common medium and coarse roots; many very fine interstitial pores; 10 percent cobbles; 40 percent pebbles; medium acid (pH 5.8); clear wavy boundary. (The combined thickness of the A horizon is 10 to 16 inches)
Bw1--13 to 27 inches; brown (10YR 5/3) very gravelly loam, dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine, fine and medium and common coarse roots; many very fine interstitial and common very fine tubular pores; 10 percent cobbles, 50 percent pebbles; medium acid (pH 6.0); clear wavy boundary.
Bw2--27 to 36 inches; pale brown (10YR 6/3) very cobbly loam, brown (10YR 4/3) moist, weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium and coarse roots; many very fine interstitial pores; 10 percent stones, 15 percent cobbles and 30 percent pebbles; medium acid (pH 6.0); abrupt irregular boundary. (The combined thickness of the Bw horizon is 20 to 30 inches)
R--36 inches; hard andesite; a few horizontal pockets of fine and medium roots; weathered in somewhat of a rind.
TYPE LOCATION: Lassen County, California; about 7 miles N along Eaglelake road (County Road A-1) from its intersection with HWY 36 and 0.5 mile past the summit then W along dirt road; 3000 feet S and 100 feet E of NW corner of section 32, T.31 N., R.11 E.
RANGE IN CHARACTERISTICS: The thickness of the umbric epipedon ranges from 20 to 30 inches. Depth to bedrock ranges from 20 to 40 inches. The mean annual soil temperature varies from 42 to 46 degrees F. The soil moisture control section (12 inches to bedrock) is dry from July 15th to November 1st (107 days) and is moist in some or all parts the rest of the time. The soil temperature exceeds 41 degrees F. from May 1st to December 1st and exceeds 47 degrees F. from June 1st to November 1st. The control section has a weighted average of 50 to 70 percent rock fragments and 8 to 15 percent clay. Base saturation ranges from 35 to 50 percent.
The A horizon dry color is 10YR 4/3, 5/3 or 7.5YR 5/4. Moist color is 10YR 3/2, 3/3 or 7.5YR 3/2. Texture is very stony loam, very gravelly sandy loam or extremely gravelly sandy loam.
The Bw1 horizon dry color is 10YR 5/3. Moist color is 10YR 3/3. Texture is very gravelly loam, very cobbly loam or extremely gravelly loam. Reaction is medium acid or strongly acid.
The Bw2 horizon dry color is 10YR 6/3, 6/4 or 7.5YR 5/4. Moist color is 10YR 3/4, 4/3 or 7.5YR 4/4. Texture is very gravelly loam, very cobbly loam or extremely gravelly loam. Reaction is medium acid or strongly acid.
COMPETING SERIES: These are the Donegan (OR), Easte (T CA) and Tallac (CA) series. The Easte and Tallac series lack bedrock within 40 inches. The Donegan soil is ?????
GEOGRAPHIC SETTING: Roop soils are on north-facing mountain back slopes. Slopes are 5 to 50 percent. These soils formed in material weathered from basalt, andesite and volcanic ash. Elevation is 6000 to 7600 feet. The mean annual precipitation is 20 to 30 inches, occurring mostly as snowfall. The mean annual temperature is about 44 degrees F. The frost-free season is about 60 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Eaglelake and Outland soils and the competing Easte soil. Eaglelake soils lack bedrock within 40 inches and are fine-loamy. Outland soils have argillic horizons and have soft bedrock at a depth of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; runoff is medium to rapid; moderately rapid permeability.
USE AND VEGETATION: Used for timber and Christmas tree production. Vegetation is white fir, red fir, Western white pine, manzanita, sierra chinkapin and ceanothous.
DISTRIBUTION AND EXTENT: Northeastern California, on Roop and Worly mountains and Susanville Peak. These soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Lassen County, California, Susanville Area, California, Parts of Lassen and Plumas Counties, Soil Survey Area; 1988.
REMARKS:
Diagnostic horizons and diagnostic features recognized in the profile:
Umbric epipedon - 0 to 27 inches, (A1, A2, Bw1); ranges from 20 to 30 inches thick.
Cambic Horizon - 13 to 36 inches (Bw1, Bw2); ranges from 10 to 24 inches thick.