LOCATION MUNJAR CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Typic Durixeralfs
TYPICAL PEDON: Munjar gravelly loam, on a southwest facing 1 percent slope under a cover of annual grasses at an elevation of 275 feet, (84 m). When described on 4/10/1999 the soil was dry to a depth of 9 inches, (23 cm) and was slightly moist from 9 to 46 inches, (23 to 117 cm). (Colors are for dry soil unless otherwise noted).
A--0 to 2 inches, (0 to 5 cm); light brown (7.5YR 6/4) gravelly loam, brown (7.5YR 4/3) moist; 20 percent clay; strong fine and medium subangular blocky parting to strong fine granular structure; hard, friable, slightly sticky, slightly plastic; many very fine roots; many very fine and fine vesicular and tubular pores; 15 percent andesite gravel; slightly acid, pH 6.5 by Hellige-Truog; abrupt smooth boundary. (1 to 2 inches, (3 to 5 cm) thick)
Bt1--2 to 5 inches, (5 to 13 cm); light brown (7.5YR 6/4) gravelly loam, brown (7.5YR 4/3) moist; 23 percent clay; moderate medium platy parting to moderate medium and coarse subangular blocky structure; hard, friable, slightly sticky, slightly plastic; common very fine roots; few medium and coarse vesicular and tubular and common very fine vesicular and tubular pores; 80 percent continuous distinct clay films on faces of peds; 30 percent andesite gravel; neutral, pH 6.7 by Hellige-Truog; clear smooth boundary. (3 to 5 inches, (8 to 13 cm) thick)
Bt2--5 to 9 inches, (13 to 23 cm); light brown (7.5YR 6/4) gravelly loam, brown (7.5YR 4/3) moist; 26 percent clay; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky, slightly plastic; common very fine roots; few medium vesicular and tubular and many very fine vesicular and tubular pores; 100 percent continuous distinct clay films on faces of peds; 2 percent andesite cobbles and 15 percent andesite gravel; neutral, pH 7.0 by Hellige-Truog; gradual smooth boundary.
Bt3--9 to 16 inches, (23 to 41 cm); brown (7.5YR 5/4) gravelly loam, brown (7.5YR 4/3) moist; 24 percent clay; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky, slightly plastic; common very fine roots; many very fine, fine and medium vesicular and tubular pores; 100 percent continuous distinct clay films on faces of peds; 10 percent andesite cobbles and 20 percent andesite gravel; neutral, pH 7.0 by Hellige-Truog; clear smooth boundary.
Bt4--16 to 22 inches, (41 to 56 cm); brown (7.5YR 5/4) extremely gravelly clay loam, dark brown (7.5YR 3/4) moist; 28 percent clay; moderate fine and medium subangular blocky structure; hard, friable, moderately sticky, moderately plastic; common very fine roots; many very fine and fine vesicular and tubular pores and many medium vesicular and tubular pores; 100 percent continuous distinct clay films on faces of peds; 25 percent andesite cobbles and 40 percent andesite gravel; slightly alkaline, pH 7.4 by Hellige-Truog; abrupt smooth boundary. (Combined thickness of the Bt2 through Bt4 horizons is 17 to 24 inches, (43 to 61 cm) thick).
2Btq--22 to 31 inches, (56 to 79 cm); brown (7.5YR 5/4) extremely cobbly sandy clay, dark brown (7.5YR 3/4) moist; 37 percent clay; massive; very hard, firm, noncemented, moderately sticky, moderately plastic; few very fine roots; common very fine, fine and medium vesicular and tubular pores; 100 percent continuous distinct clay films on rock fragments; 35 percent andesite cobbles and 35 percent andesite gravel; slightly alkaline, pH 7.6 by Hellige-Truog; gradual smooth boundary. (0 to 9 inches, (0 to 23 cm) thick)
2Btqm--31 to 46 inches, (79 to 117 cm); strongly cemented duripan; brown (7.5YR 5/4) extremely gravelly sandy clay loam, brown (7.5YR 4/3) moist; 27 percent clay; massive; very hard, firm, strongly cemented, cemented by silica, moderately sticky, moderately plastic; few very fine roots; common very fine and fine vesicular and tubular pores; 100 percent continuous distinct clay films on rock fragments; 5 percent andesite stones and 35 percent andesite cobbles and 40 percent andesite gravel; slightly alkaline, pH 7.8 by Hellige-Truog.
TYPE LOCATION: Butte County, California, about 6.3 miles northeast of Nord, approximately 1100 feet west and 2300 feet south of the northeast corner of Section 7, Township 23 N., Range 1 E., 39 degrees, 51 minutes, 47 seconds North latitude and 121 degrees, 53 minutes, 14 seconds West longitude, NAD27 - U.S.G.S. Quad: Nord, California.
RANGE IN CHARACTERISTICS: Depth to extremely gravelly duripan is 20 to 40 inches, (51 to 102 cm). The mean annual soil temperature is 62 to 64 degrees F, (17 to 18 degrees C). The particle-size control section averages 27 to 30 percent clay and 35 to 45 percent rock fragments, mostly gravel and cobbles. Mineralogy is mixed. A fluctuating water table can occur between the top of the duripan and 12 inches, (30 cm) below the surface of the soil from December through April. Rock fragments on the surface range from 5 to 30 percent gravel.
The A horizon dry color is 7.5YR 6/4. Moist color is 7.5YR 4/3 or 5YR 3/3. Texture is gravelly loam. Clay content ranges from 20 to 24 percent. Organic matter ranges from 2 to 5 percent. Rock fragments range from 15 to 30 percent gravel. Reaction ranges from slightly acid to neutral.
The Bt1 horizon dry color is 7.5YR 6/4 or 6/6. Moist color is 7.5YR 4/3 or 5YR 4/3. Texture is gravelly loam. Clay content ranges from 23 to 24 percent. Organic matter ranges from 0.8 to 1.2 percent. Rock fragments range from 15 to 30 percent gravel. Reaction ranges from slightly acid to neutral.
The Bt2 through Bt4 horizons dry color is 7.5YR 5/4, 6/4, 6/6 or 5YR 5/4. Moist color is 7.5YR 3/4, 4/3 or 5YR 4/3. Texture is gravelly loam, extremely gravelly clay loam, very gravelly loam or very cobbly clay loam. Clay content ranges from 24 to 35 percent. Organic matter ranges from 0.5 to 0.8 percent. Rock fragments range from 15 to 40 percent gravel, 2 to 40 percent cobbles, and 0 to 5 percent stones. Reaction ranges from neutral to slightly alkaline.
The 2Btq horizon dry color is 7.5YR 5/4. Moist color is 7.5YR 3/4. Texture is extremely cobbly sandy clay. Clay content ranges from 35 to 40 percent. Organic matter ranges from 0 to 0.5 percent. Rock fragments range from 30 to 35 percent gravel and 20 to 35 percent cobbles. Reaction ranges from neutral to slightly alkaline.
The 2Btqm horizon dry color is 7.5YR 5/4. Moist color is 7.5YR 3/4. Texture is extremely gravelly sandy clay loam. Clay content ranges from 27 to 35 percent. Rock fragments range from 40 to 45 percent gravel, 10 to 35 percent cobbles, and 0 to 5 percent stones. Reaction ranges from neutral to slightly alkaline.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Munjar soils are on bars on fan terraces. Slopes range from 0 to 2 percent. These soils formed in reworked alluvium weathered from predominantly volcanic rocks. Elevation is 190 to 380 feet, (623 to 1247 m). Mean annual precipitation is 23 to 28 inches, (584 to 711 mm). The mean annual temperature is 60 to 62 degrees F, (16 to 17 degrees C). Frost-free season is 240 to 260 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Galt, Redsluff, Redswale, Redtough and Tuscan soils. Galt soils are moderately deep to duripan, are fine, and are in small basins or depressions. Redsluff soils are very deep, fine-loamy and are on low terraces. Redswale soils are very shallow, poorly drained, loamy-skeletal and are in swales. Redtough soils are shallow, somewhat poorly drained, loamy and are on mounds. Tuscan soils are shallow, clayey and are on linear ridges or mounds.
DRAINAGE AND PERMEABILITY: Moderately well drained; high runoff; moderate saturated hydraulic conductivity in the A and Bt1 horizons, moderately slow in the Bt2, Bt3 and Bt4 horizons, moderately slow in the 2Btq horizon and impermeable in the 2Btqm horizon. A fluctuating water table can occur between the top of the duripan and 12 inches, (30 cm) below the surface of the soil from December through April.
USE AND VEGETATION: This soil is used for livestock grazing, wildlife habitat, watershed and home site development. Vegetation is red brome, soft chess, wild oat, clover, filaree, buttercups and yellow starthistle.
DISTRIBUTION AND EXTENT: Butte County, California and occurs in the (262Ab) Northern Eastside Terraces subsection of the (262A) Great Valley section. MLRA: 17 - Sacramento Valley. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Butte County, California 2005. Source of name from Munjar Road.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - zone from 0 to 5 inches, (0 to 13 cm) (A, Bt1)
Argillic horizon - zone from 5 to 31 inches, (13 to 79 cm) (Bt2, Bt3, Bt4, 2Btq)
Duripan - zone from 31 to 46 inches, (79 to 117 cm) (2Btqm)
Particle-size control section for this pedon: zone from 5 to 25 inches, (13 to 63 cm).
The soil moisture control section - zone from 8 to 31 inches, (20 to 79 cm) is dry in all parts from about June to October (about 180 days).