LOCATION ARMISTEAD LA
Established Series
Rev. JPE:WLC:MJB
01/2017
ARMISTEAD SERIES
The Armistead series consists of very deep, somewhat poorly drained, soils that formed in reddish clayey over loamy alluvium. These soils are on nearly level to very gently sloping alluvial plains of the Red River. Slopes range from 0 to 1 percent. Mean annual air temperature is about 17.3 degrees C (63.2 degrees F), and mean annual precipitation is about 1306 mm (51.42 in).
TAXONOMIC CLASS: Fine-silty, mixed, active, thermic Aquic Pachic Argiudolls
TYPICAL PEDON: Armistead clay, on a north facing, 0.5 percent slope in a cultivated field; elevation is 43 m (142 feet). (Colors are for moist soil unless otherwise stated.)
Ap--0 to 15 cm (0 to 6 in); dark reddish brown (5YR 3/2) moist, clay; dark reddish gray (5YR 4/2) dry; strong and moderate medium subangular blocky structure; firm, very hard; many fine and common medium roots; common fine irregular pores; noneffervescent by HCL, 1 normal; slightly alkaline; gradual smooth boundary.
A--15 to 35 cm (6 to 14 in); dark reddish brown (5YR 3/3) moist, clay; reddish brown (5YR 4/3) dry; strong and moderate medium subangular blocky structure; firm, very hard; common fine and medium roots; common fine irregular pores; noneffervescent by HCL, 1 normal; moderately alkaline; clear smooth boundary. (Combined thickness of A horizons is 25 to 50 cm [10 to 20 in])
2Ab1--35 to 47 cm (14 to 19 in); very dark gray (5YR 3/1) moist, silty clay loam; moderate medium subangular blocky structure; firm, hard; common fine and medium roots; common very fine pores; 15 percent medium faint black (5YR 2.5/1) manganese masses; few fine prominent gray (10YR 5/1) moist, masses of reduced iron with diffuse boundaries in matrix; 8 percent dark reddish brown (5YR 3/3) bodies of silt loam; noneffervescent, by HCL, 1 normal; moderately alkaline; gradual smooth boundary.
2Ab2--47 to 62 cm (19 to 24 in); dark reddish brown (5YR 3/2) moist, silty clay loam; moderate coarse prismatic structure parting to moderate medium subangular blocky firm, very hard; common fine and medium roots; common fine and very fine irregular pores; 15 percent medium, faint black (5YR 2.5/1) manganese masses; 1 percent fine prominent gray (10YR 5/1) moist, masses of reduced iron with diffuse boundaries in matrix; noneffervescent, by HCl, 1 normal; moderately alkaline, diffused smooth boundary. (Combined thickness of 2Ab horizons is 15 to 31 cm [6 to 12 in])
2Bt1--62 to 85 cm (24 to 33 in); yellowish red (5YR 4/6) silty clay loam; moderate coarse prismatic structure parting to moderate medium subangular blocky; firm, moderately hard; common fine roots, common fine irregular and many very fine irregular pores; 50 percent faint reddish brown (5YR 4/4) moist, clay films on all ped faces; few fine irregular carbonate nodules in the matrix; very slight effervescence, by HCl, 1 normal; moderately alkaline; gradual wavy boundary.
2Bt2--85 to 110 cm (33 to 43 in); yellowish red (5YR 4/6) silty clay loam; moderate medium subangular blocky structure; firm, slightly hard; common fine roots; common very fine irregular pores; 40 percent faint reddish brown (5YR 4/4) moist, clay films, on all faces of peds; few fine distinct black (5YR 2.5/1) moist, manganese masses; noneffervescent, by HCl, 1 normal; moderately alkaline; gradual smooth boundary.
2Bt3--110 to 135 cm (43 to 53 in); yellowish red (5YR 5/6) silt loam; weak medium subangular blocky structure parting to weak fine subangular blocky; friable, slightly hard; common fine roots; many very fine irregular pores; 20 percent faint reddish brown (5YR 4/4) moist, clay films on all ped faces; 3 percent fine distinct black (5YR 2.5/1) moist, manganese masses; noneffervescent by HCl, 1 normal; moderately alkaline; clear smooth boundary. (Combined thickness of the 2Bt horizons is 46 to 100 cm [18 to 40 in])
2C1--135 to 161 cm (53 to 63 in); 55 percent reddish brown (5YR 4/4) and 45 percent yellowish red (5YR 5/6) stratified silty clay loam to silt loam; structureless, massive; firm, moderately hard; common medium roots; common fine irregular and common very fine irregular pores; strong effervescence, by HCl, 1 normal; moderately alkaline, clear smooth boundary.
2C2--161 to 182 cm (63 to 72 in); 60 percent reddish yellow (5YR 6/6) and 40 percent yellowish red (5YR 5/6) very fine sandy loam; structureless, massive; very friable, soft; common very fine irregular pores; noneffervescent, by HCl, 1 normal; moderately alkaline; gradual smooth boundary.
2C3--182 to 203 cm (72 to 80 in); yellowish red (5YR 5/6) silt loam; structureless massive; very friable, soft; common very fine irregular pores; noneffervescent, by HCl, 1 normal; slightly alkaline; common bedding planes of reddish yellow (5YR 6/6).
TYPE LOCATION: Red River Parish, Louisiana; 6,200 feet west of Williams, Louisiana; 960 feet north from center of south section line; 1,560 feet west from local road; SE1/4 SW1/4 sec. 16, T. 14 N., R. 11W.
USGS Topographic Quadrangle: Clear Lake, LA
Latitude: 32 degrees, 11 minutes, 48.30 seconds N
Longitude: 93 degrees, 30 minutes, 18.2 seconds W
Decimal Degrees:
Latitude: 32.1967494 degrees
Longitude: -93.5050556 degrees
Datum: NAD 83
UTM Easting: 452396.7 m
UTM Northing: 3562356.1 m
UTM Zone: 15N
RANGE IN CHARACTERISTICS:
Solum thickness: 100 to 178 cm (40 to 70 in)
Depth to argillic horizon: 50 to 81 cm (20 to 32 in)
Depth to redox features: 0 to 40 cm (0 to 16 in)
Depth of clayey upper horizons: 25 to 50 cm (10 to 20 in)
Particle-size control section (weighted average):
Clay content: 18 to 30 percent
Sand content: 10 to 40 percent
CEC/clay ratio: 0.40 to 0.60
A or Ap horizon:
Hue: 2.5YR to 7.5YR
Value: 2 or 3
Chroma: 2 or 3
Texture: silty clay or clay
Clay content: 40 to 55 percent
Redox concentrations: amount-none to common; size-medium; contrast-distinct; colors-shades of brown; boundary-diffuse; location-throughout
Redox depletions: amount-none to common; size-medium; contrast-distinct; color-shades of gray; boundary-diffuse; location-throughout
Iron-manganese nodules: amount-0 to 3 percent
Reaction: slightly acid to moderately alkaline
2Ab horizon:
Hue: 2.5YR to 7.5YR
Value: 3
Chroma: 1 to 3
Texture: silt loam or silty clay loam
Clay content: 14 to 30 percent
Redox concentrations: amount-none to common; size-medium; contrast-distinct; color-shades of brown; boundary-diffuse; location-throughout
Redox depletions: amount-few to many; size-medium; contrast-distinct; color-shades of gray or grayish brown; boundary-diffuse; location-throughout
Iron-manganese concentrations: amount-0 to 3 percent
Reaction: neutral to moderately alkaline)
2Bt horizon:
Hue: 2.5YR or 5YR
Value: 4 or 5
Chroma: 4 to 8
Texture: silt loam or silty clay loam
Clay content: 14 to 30 percent
Clay films: amount-1 to 60 percent; location-on faces of peds
Redox concentrations: amount-none to common; size-medium; contrast-distinct; color-shades of brown; boundary-diffuse; location-throughout
Redox depletions: amount-none to common; size-fine or medium; contrast-distinct; colors-shades of gray and grayish brown; boundary-diffuse; location-throughout
Iron-manganese concentrations: 0 to 3 percent
Reaction: slightly acid to moderately alkaline
2BC horizon (where present):
Hue: 2.5YR or 5YR
Value: 4 or 5 Chroma: 4 to 8
Texture: variable ranging from very fine sandy loam to clay
Clay content: 10 to 50 percent
Redox concentrations: amount-none to common; size-medium; contrast-distinct; color-shades of brown; boundary-diffuse; location-throughout
Redox depletions: amount-none to common; size-fine or medium; contrast-distinct; colors-shades of gray and grayish brown; boundary-diffuse; location-throughout
Iron-manganese concentrations: 0 to 3 percent
Reaction: neutral to moderately alkaline
2C horizon:
Hue: 2.5YR to 7.5YR
Value: 4 to 6
Chroma: 4 to 8
Texture: variable or stratified ranging from very fine sandy loam to clay
Clay content: 10 to 50 percent
Carbonates: amount-0 to 5 percent; kind-nodules or concretions
Reaction: neutral to moderately alkaline
COMPETING SERIES: There are no other series in the same family. Similar soils are the
Ashwood (TN),
Benklin (TX),
Bonham (TX),
Buxin (LA),
Caspiana (LA),
Dennis (OK),
Desha (AR),
Eram (OK),
Garton (OK),
Latanier (LA),
Mason (OK),
Moreland (LA),
Mer Rouge (LA),
Pledger (TX),
Roebuck (OK),
Reelfoot (TN), and
Tiptonville (TN) series.
Ashwood,
Buxin,
Desha,
Moreland,
Pledger and
Roebuck soils: are clayey to depths of 100 cm (40 in) or more
Benklin soils: have hues of 7.5YR or yellower below the mollic epipedon
Bonham,
Caspiana,
Mason,
Mer Rouge,
Reelfoot and
Tiptonville soils: are not clayey in horizons in the 25 to 50 cm (10 to 40 in) control section
Dennis,
Eram and
Garton soils: have fine-textured argillic horizons
Latanier soils: do not have argillic horizons and have 51 to 91 cm (20 to 36 in) of clayey material over loamy 2C horizons
GEOGRAPHIC SETTING:
Parent material: Holocene age clayey alluvium over loamy alluvium derived from Red River sediments
Landscape: Red River alluvial plains
Landform: natural levees on flood plains
Slope: 0 to 1 percent
Soil Moisture: An udic soil moisture regime
Mean annual soil temperature: 19.3 to 21 degrees C (67 to 70 degrees F)
Mean annual air temperature: 14.0 to 19.0 degrees C (57 to 66 degrees F)
Mean annual precipitation range: 1295 to 1548 mm (51 to 61 in)
Precipitation Pattern: The soil moisture control section is not dry in any part for more than 90 days in normal years. June through November are the driest months, while December through May is the wettest.
Frost-free period: 250 to 293 days
Elevation: 27.4 to 61.0 m (90 to 200 ft)
Thornthwaite annual P-E indices: 81 to 128
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Buxin (LA),
Caspiana (LA),
Gallion (LA),
Latanier (LA) and the
Moreland (LA) series.
Buxin soils: are clayey to depths of 100 cm (40 in) or more and are on lower flood plain steps
Caspiana and
Gallion soils: are loamy throughout and are on higher flood plain steps on natural levees
Latanier soils: have 50 to 100 cm (20 to 40 in) of clay over loamy material on lower positions on the flood plain
Moreland soils: are clayey to depths of more than 100 cm (40 in) and are on lower flood plain steps
DRAINAGE AND PERMEABILITY:
Drainage: somewhat poorly drained
Permeability: slow
Runoff: low
Seasonal high water table: An apparent water table at a depth of 46 to 91 cm (18 to 36 in) during the months of December through April in normal years.
USE AND VEGETATION: Areas protected by levees have been cleared and are used for cotton, soybeans, small grain, hay, and pasture. Native vegetation is mixed hardwoods, cottonwood, cherrybark oak, water oak, sweetgum, pecan, sycamore, green ash, and hackberry.
DISTRIBUTION AND EXTENT: Louisiana; Land Resource Region O; MLRA 131C. This series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Red River Parish, Louisiana; 1973. The name is from a nearby community.
REMARKS:
These soils were formerly classified in the Alluvial great soil group. These soils are considered to have argillic horizons, though the 2Bt horizons do not have the required clay increase for an argillic horizon. The higher clay content in the 2A horizon is due to mixing with the overwash clay A horizon.
Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: 62 to 112 cm (24 to 44 in) (2Bt1, 2Bt2 and 2 Bt3 horizons)
Mollic epipedon: 0 to 62 cm (0 to 24 in) (Ap, A and 2Ab horizons)
Argillic horizon: 62 to 135 cm (24 to 53 in) (2Bt1, 2Bt2 and 2Bt3 horizons)
Redoximorphic depletions: 35 to 62 cm (14 to 24 in) (2Ab horizons)
Lithologic discontinuity: upper boundary of the 2Ab horizon 35 cm (14 in)
The assignment of the cation-exchange activity class is supported by KSSL laboratory data number S2010LA081001 from Red River Parish, Louisiana.
Edited 01/2017 (JAD-MJB) Changed to tabular format. Updated pedon description, Range in Characteristics, and other sections.
ADDITIONAL DATA: KSSL data is from type location S2010LA081001 Red River Parish, Louisiana.
Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.