LOCATION LONGBELL CAEstablished Series
TAXONOMIC CLASS: Medial over sandy or sandy-skeletal, mixed,
mesic Humic Vitrixerands
TYPICAL PEDON: Longbell gravelly coarse sandy loam on a northeast-facing 2 percent slope under a cover of ponderosa pine, antelope bitterbrush and bottlebrush squirreltail at an elevation of 4279 feet. (Colors are for dry soil unless otherwise stated. When described May 14, 1984, the soil was slightly moist throughout.)
Oi--2 to 0 inches; recent and decomposed pine needles.
A1--0 to 3 inches; brown (10YR 5/3) gravelly coarse sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine subangular blocky structure; loose, nonsticky and nonplastic; many very fine roots; common very fine interstitial pores; 20 percent fine gravel; NaF ph 10.0; slightly acid (pH 6.5); abrupt smooth boundary.
A2--3 to 11 inches; brown (10YR 5/3) gravelly loamy coarse sand, very dark grayish brown (10YR 3/2) moist; weak very fine subangular blocky structure; soft, loose, nonsticky and nonplastic; common very fine and few coarse and medium roots; common very fine interstitial pores; 20 percent fine gravel; NaF pH 10.0; slightly acid (pH 6.5); clear smooth boundary. (Combined thickness of the A horizons are 10 to 18 inches).
Bw1--11 to 18 inches; pale brown (10YR 6/3) gravelly loamy coarse sand, brown (10YR 4/3) moist; single grained; loose, nonsticky and nonplastic; few fine and coarse roots; common very fine interstitial pores; 20 percent fine gravel; NaF pH 10.5; neutral (pH 7.0); abrupt smooth boundary. (4 to 15 inches thick)
2Bw2--18 to 30 inches; pale brown (10YR 6/3) gravelly loamy coarse sand, brown (10YR 4/3) moist; single grained; loose, nonsticky and nonplastic; few medium and coarse roots; common very fine interstitial pores; 20 percent fine gravel; NaF pH 10.0; neutral (pH 7.0); clear smooth boundary.
2Bw3--30 to 42 inches; pale brown (10YR 6/3) gravelly loamy sand, brown (10YR 4/3) moist; single grained; loose, nonsticky and nonplastic; few medium roots; common very fine interstitial pores; 20 percent gravel; NaF pH 9.6; neutral (pH 7.0); clear smooth boundary. (Combined thickness of the 2Bw horizon is 18 to 27 inches thick)
2C1--42 to 52 inches; very pale brown (10YR 7/3) very gravelly sand, brown (10YR 4/3) moist; single grained; loose, nonsticky and nonplastic; few medium roots; common fine interstitial pores; 40 percent fine gravel; NaF pH 8.5; neutral (pH 7.0); gradual smooth boundary.
2C2--52 to 54 inches; very pale brown (10YR 7/3) very gravelly sand, brown (10YR 5/3) moist; single grained; loose, nonsticky and nonplastic; few fine roots; common fine interstitial pores; 50 percent fine cinder gravel; NaF pH 7.8; neutral (pH 7.0); abrupt smooth boundary.
2C3--54 to 72 inches; very pale brown (10YR 7/3) very gravelly sand; brown (10YR 5/3) moist; single grained; loose, nonsticky and nonplastic; few fine roots; common fine interstitial pores; 50 percent fine cinder gravel; NaF pH 7.7; neutral (pH 7.0). (Combined thickness of the C horizons are 10 to 30 inches or more thick)
TYPE LOCATION: Modoc County, California; about 1.2 miles north of Longbell Fire Station, 200 feet east of logging road; 1,000 feet west and 1,400 feet south of the northeast corner of sec. 17, T. 42 N., R. 5 E., Whitehorse NW (Border Mtn.) quadrangle (7.5 minute series).
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 49 degrees F. The soil temperature exceeds 41 degrees F. from mid March to late December (285 days) and exceeds 47 degrees F. from early May to early December. The soil moisture control section (12 to 36 inches) is dry in all parts from early June to late September (110 to 120 days) and is moist in all parts from early November to early May. The particle size control section (0 to 40 inches) ranges from 3 to 18 percent clay and 15 to 30 percent rock fragments, mostly fine gravel. Reaction is slightly acid to neutral, increasing with depth.
The A horizon color is 10YR 5/2 or 5/3. Moist color is 10YR 3/2, 3/3 or 4/2. Organic matter ranges from 2.0 to 3.0 percent. Rock fragments, mostly gravel, range from 15 to 30 percent. NaF pH is 10 to 10.5. Base saturation by ammonium acetate ranges from 34 to 38 percent.
The Bw1 horizon color is 10YR 6/3, 6/4, or 7/3. Moist color is 10YR 4/3, or 4/4. Organic matter ranges from 0.6 to 1.0 percent. Rock fragments mostly gravel range from 15 to 30 percent. NaF pH is 9.6 to 10.0. Base saturation by ammonium acetate ranges from 40 to 50 percent.
The 2Bw2 and 2Bw3 horizon color is 10YR 6/3, 6/4, or 7/3. Moist color is 10YR 4/3, or 4/4. Organic matter ranges from 0.3 to 0.5 percent. Clay content ranges from 3 to 5 percent. Rock fragments mostly gravel range from 15 to 30 percent. NaF pH is 9.6 to 10.0. Base saturation by ammonium acetate ranges from 40 to 60 percent.
The C horizon color is 10YR 6/3, 6/4, 7/3, or 7/4. Moist color is 10YR 5/3, 4/3, or 4/4. Organic matter ranges from 0.1 to 0.3 percent. Clay content ranges from 2 to 5 percent. Rock fragments mostly gravel range from 35 to 60 percent. NaF pH is 7.7 to 8.5. Base saturation by ammonium acetate ranges from 50 to 80 percent.
Andic property data (see glossary for explanation):
Depth P-ret B.D. pH NaF Glass Alo Feo 15 barH20
0-3 76 NC 10.2 23 2.04 0.54 12.9
3-11 80 0.90 10.1 17 2.39 0.81 11.9
11-18 82 0.90 10.1 7 2.62 0.62 14.2
18-30 72 1.11 10.0 2 2.50 0.63 12.8
30-42 61 NC 9.6 ND 1.56 0.88 10.8
42-52 35 NC 8.5 ND 0.50 1.11 10.0
52-54 ND NC 7.9 ND ND ND 9.3
54-72 ND NC 7.8 ND ND ND 9.7
COMPETING SERIES: There are no competing series in this family.
GEOGRAPHIC SETTING: Longbell soils are on lava plateaus. Slopes are 2 to 15 percent. These soils formed from tephra deposited over volcanic outwash. Elevation is 4,100 to 5,000 feet. The climate is subhumid with warm dry summers and cold moist winters. Mean annual precipitation is 16 to 25 inches. Snowfall is 48 to 60 inches. The mean annual temperature is 45 to 48 degrees F., the mean January temperature is about 32 degrees F. The mean July temperature is about 65 degrees F. Frost-free period is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fleener, Loveness, Blankout and Medici soils. Fleener soils are on hills and lava plateaus, have argillic horizons and are loamy-skeletal. Loveness soils are on hills and lava plateaus, have argillics and are fine-loamy. Blankout soils are on hills and have ochric epipedons, are over 60 inches deep to bedrock. Medici are on hills, have ochric epipedons and are medial over loamy-skeletal.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; slow or medium runoff; moderately rapid permeability over very rapid in the lower part of the profile.
USE AND VEGETATION: This soil is used for timber production. The vegetation is ponderosa pine, antelope bitterbrush, and bottlebrush squirreltail, bloomer goldenbush and needlegrass.
DISTRIBUTION AND EXTENT: Northeastern California. The soils are not extensive. MLRA is 22.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Modoc County, Intermountain Soil Survey Area, California, 1994.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Umbric epipedon - the zone from 0 to 11 inches (A1, A2 horizons)
Clay percentage not determined from 0 to 30 inches(A1, A2, Bw1, and 2Bw2 horizons).
Andic properties data definitions:
P-ret: phosphate retention of the less than 2mm fraction.
B.D.: bulk density of the less than 2mm fraction on an oven dry basis.
pH NaF: pH of soil mixed with saturated sodium floride solution.
Glass: percent volcanic glass.
Alo: acid-oxalate-extractable aluminum of the less than 2mm fraction.
Feo: acid-oxalate-extractable iron of the less than 2mm fraction.
15 bar H20: dried 1500 kPa water retention as a percent.
Data elements with a * are estimated.
NC: not calculated.
ND: not done.
ADDITIONAL DATA: This pedon was characterized by U.C. Davis Laboratory in 1984. Pedon number is 85-CA-049-02X, lab no. 1618, unpublished.