LOCATION PARROTT CAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Fluventic Haploxerepts
TYPICAL PEDON: Parrott silt loam, on a 1 percent slope under a cover of walnuts at an elevation of 151 feet, (46 m). When described on 10/26/1988 the soil was dry throughout. (Colors are for dry soil unless otherwise noted).
A1--0 to 2 inches, (0 to 4 cm); light brownish gray (2.5Y 6/2) silt loam, very dark grayish brown (2.5Y 3/2) moist; 22 percent clay; moderate fine platy structure; slightly hard, friable, slightly sticky, slightly plastic; many very fine roots; many very fine tubular pores; neutral, pH 7.2 by Hellige-Truog; abrupt smooth boundary.
A2--2 to 8 inches, (4 to 20 cm); grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; 23 percent clay; moderate fine and medium platy structure; slightly hard, friable, slightly sticky, slightly plastic; common very fine roots; many very fine irregular and tubular pores; neutral, pH 7.2 by Hellige-Truog; clear smooth boundary. (Combined thickness of the Ap horizon is 7 to 10 inches, (18 to 25 cm) thick).
Bw1--8 to 20 inches, (20 to 52 cm); light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; 21 percent clay; weak fine subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; few very fine and fine roots; many very fine irregular and tubular pores; 8 percent silt coats on surfaces along pores; 1 percent medium dark grayish brown (10YR 4/2), manganese masses and 25 percent medium brown (7.5YR 5/4) oxidized iron masses; neutral, pH 7.2 by Hellige-Truog; clear smooth boundary.
Bw2--20 to 37 inches, (52 to 95 cm); light brownish gray (10YR 6/2) silt loam, dark brown (10YR 3/3) moist; 21 percent clay; weak fine subangular blocky structure; slightly hard, friable, slightly sticky, moderately plastic; few very fine roots; common fine tubular and many very fine tubular pores; 8 percent silt coats on surfaces along pores; 10 percent medium brown (7.5YR 4/3) oxidized iron masses; neutral, pH 7.2 by Hellige-Truog; clear smooth boundary.
Bw3--37 to 49 inches, (95 to 125 cm); brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; 21 percent clay; weak fine subangular blocky structure; slightly hard, friable, slightly sticky, moderately plastic; few very fine and fine roots; few fine tubular and many very fine tubular pores; 8 percent light brownish gray (10YR 6/2) silt coats on surfaces along pores; neutral, pH 7.2 by Hellige-Truog; clear smooth boundary.
Bw4--49 to 63 inches, (125 to 160 cm); pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; 19 percent clay; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky, moderately plastic; few fine roots; few fine tubular and many very fine tubular pores; neutral, pH 7.2 by Hellige-Truog; clear smooth boundary. (Combined thickness of the Bw horizon is 50 to 60 inches, (127 to 152 cm) thick).
C--63 to 89 inches, (160 to 225 cm); yellowish brown (10YR 5/4) silt loam, dark yellowish brown (10YR 3/4) moist; 17 percent clay; massive; slightly hard, very friable, slightly sticky, moderately plastic; few fine roots; few fine tubular and many very fine tubular pores; neutral, pH 7.2 Hellige-Truog; clear smooth boundary. (25 to 35 inches, (63 to 89 cm) thick)
TYPE LOCATION: Butte County, California; about 3.8 miles northeast of Nord, approximately 2200 feet north and 1700 feet east of the intersection of Township 22 N. and 23 N. and Range 1 W. and 2 W., 39 degrees, 48 minutes, 13 seconds North latitude and 122 degrees, 1 minutes, 23 seconds West longitude, NAD27 - U.S.G.S. Quad: Foster Island, California.
RANGE IN CHARACTERISTICS: Depth is greater than 80 inches, (203 cm). The mean annual soil temperature is 60 to 64 degrees F, (16 to 18 degrees C). The particle-size control section averages 18 to 27 percent clay. Mineralogy is mixed. Organic matter decreases regularly with depth and ranges from 1 to 5 percent to a depth of 49 inches, (124 cm) and is less than 1.0 percent to a depth of 89 inches, (226 cm). Base saturation by ammonium acetate is 100 percent throughout. A fluctuating water table can occur at depths of 60 inches, (152 cm) or more below the surface of the soil from December through March. Redoximorphic features such as iron masses and manganese masses occur in both the Ap and A horizons. Some pedons have gravelly substratum below 40 inches, (102 cm) and or have disseminated lime between 45 to 72 inches (114 o 183cm).
The A horizon dry color is 2.5Y 6/2, 10YR 5/2, 5/3 or 6/3. Moist color is 2.5Y 3/2, 10YR 3/2, 3/3, 4/2 or 4/3. Texture is silt loam. Clay content ranges from 18 to 27 percent. Reaction ranges from slightly acid to slightly alkaline.
The Bw horizon dry color is 10YR 5/3, 5/4 or 6/3. Moist color is 10YR 3/3, 3/4 or 4/3. Texture is silt loam. Clay content ranges from 18 to 27 percent. Reaction ranges from neutral to slightly alkaline.
The C horizon dry color is 10YR 5/3, 5/4 or 6/3. Moist color is 10YR 3/3, 3/4 or 4/3. Texture is silt loam, loam, fine sandy loam, sandy loam, clay loam or silty clay loam. Clay content ranges from 12 to 30 percent. Rock fragments range from 0 to 5 percent gravel. Reaction ranges from neutral to slightly alkaline.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Parrott soils are on bars on flood plains. Most areas have been leveled for agriculture. Slopes range from 0 to 2 percent. These soils formed in alluvium weathered from mixed rocks. Elevation is 85 to 170 feet, (26 to 52 m). Mean annual precipitation is 18 to 23 inches, (457 to 584 mm). The mean annual temperature is 60 to 62 degrees F, (16 to 17 degrees C). Frost free season is 240 to 245 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Columbia, Farwell and Gianella soils. Columbia soils are coarse-loamy, have water tables within 20 inches, (51 cm) of the surface and are stratified. Farwell soils are fine-loamy and are in margins between floodplains and alluvial fans. Gianella soils are coarse-loamy and are on floodplains within the meander belt.
DRAINAGE AND PERMEABILITY: Moderately well drained; very low runoff; moderate saturated hydraulic conductivity in the A, Bw1, Bw2, Bw3 horizons and moderately rapid to moderately slow in the Bw4 and C horizons. The soils are occasionally to frequently flooded for very brief to brief periods in December through March. Water occasionally ponds up to 0.5 inches, (1.3 cm) above the surface for a very brief duration from December through March following intense precipitation events. A fluctuating water table can occur at depths of 60 inches, (152 cm) or more below the surface of the soil from December through March. During exceptionally wet winters the water table may be as high as 8 to 30 inches, (20 to 76 cm) below the surface of the soil from December through March.
USE AND VEGETATION: This soil is used for orchard crops such as walnuts and almonds and grain crops such as safflower, wheat and barley. Natural vegetation is valley oak and annual grasses. Most areas have been cleared for agriculture.
DISTRIBUTION AND EXTENT: Butte County, California and occur in (262Af) River alluvium subsection of the Great Valley section. MLRA: 17 - Sacramento Valley. The soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Butte County, California 2005. Source of name from the Parrott School.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric Epipedon - zone from 0 to 8 inches, (0 to 20 cm) (A1, A2)
Cambic horizon - zone from 8 to 63 inches, (20 to 160 cm) (Bw1, Bw2, Bw3, Bw4)
Particle-size control section for this pedon: 10 to 40 inches, (25 to 102 cm).
The soil moisture control section zone from 5 to 16 inches, (13 to 41 cm) is dry in all parts from about May 15 to October 31 (about 165 days).
These soils were previously mapped as Columbia loam in the soil survey of Chico Area, California 1926.
ADDITIONAL DATA: Characterization data from lab pedon number: 89P0069, NSSL, Lincoln, NE.